How Deadly Are Nightshades?

How deadly are nightshades? with potato

Nightshades have a reputation as bad actors in a variety of chronic conditions, such as arthritis, fibromyalgia, and IBS. But what do we really know about how these foods affect our health?

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Meet the Nightshade (Solanaceae) Family: 

  • Tomatoes
  • Tomatillos
  • Eggplant
  • Potatoes
  • Goji Berries
  • Tobacco
  • Peppers (bell peppers, chili peppers, paprika, tamales, tomatillos, pimentos, cayenne, etc) 

At first glance, the nightshades may look like a random collection of foods that couldn’t possibly be related.  However, every nightshade plant produces fruits that all sport that same adorable little green elfish hat.  Of the foods above, only tomatoes, eggplants, goji berries and peppers are “fruits” (the potato is a tuber and tobacco is a leaf).  The fruits of potato and tobacco plants wear the same telltale hat, but we don’t eat the fruits of those plants.

What are glycoalkaloids?

Glycoalkaloids are natural pesticides produced by nightshade plants. Glycoalkaloids are bitter compounds which are found throughout the plant, but their concentrations are especially high in leaves, flowers, and unripe fruits. They are there to defend plants against bacteria, fungi, viruses, and insects.

Cherries, apples, and sugar beets also contain small amounts of glycoalkaloid even though they are not nightshades.

How do glycoalkaloids kill pests?

  • Glycoalkaloids act as invisible hand grenades. They bind strongly to the cholesterol in the cell membranes of predators, and in so doing, they disrupt the structure of those membranes, causing cells to leak or burst open upon contact.
  • Glycoalkaloids are neurotoxins. They block the enzyme cholinesterase. This enzyme is responsible for breaking down acetylcholine, a vital neurotransmitter that carries signals between nerve cells and muscle cells. When this important enzyme is blocked, acetylcholine can accumulate and electrically overstimulate the predator’s muscle cells.  This can lead to paralysis, convulsions, respiratory arrest, and death. Military “nerve gases” work exactly the same way.

Ok, so glycoalkaloids are clearly nightmarish compounds for the cells of tiny creatures daring to munch upon nightshade plants, but what do we know about their effects on human health?

Nightshade glycoalkaloid health “benefits

Health benefits?  From a pesticide?  Hmmm…

Since most people believe plant compounds are good for humans, when scientists conduct experiments with plant extracts, they are more likely to look for health benefits than health risks.

  • Glycoalkaloids are anti-inflammatory. Glycoalkaloids have been shown to reduce inflammation in laboratory animals. This is likely due to the fact that glycoalkaloids are structurally similar to compounds called glucocorticoids, which have well-known anti-inflammatory properties. Familiar examples of glucocorticoids include cortisol (our body’s natural stress hormone), and Prednisone, a commonly-prescribed anti-inflammatory medicine. It should be noted, however, that just because glycoalkaloids or glucocorticoids can reduce inflammation doesn’t mean they are always good for you. Prednisone is not something most of us should be taking every day, because it has numerous damaging side effects, and elevated levels of natural cortisol in our bodies weaken our immune system and slow our metabolism.
  • Glycoalkaloids kill bacteria and viruses. It should also not be surprising that glycoalkaloids have been shown in laboratory studies to possess antibiotic and antiviral properties, since this is what nature designed them for.
  • Glycoalkaloids have anti-cancer properties. In laboratory (in vitro) studies, glycoalkaloids can trigger cancer cells to self-destruct.  This process is called “apoptosis.”  Unfortunately, they can also cause healthy non-cancerous cells to do the same thing. Cancer studies in live animals and humans (in vivo) have not yet been conducted. The problem with so many anti-cancer plant compounds is that they are double-edged swords, killing both cancer cells and healthy cells alike:

“…the undifferentiating destruction of both cancer and noncancerous cell lines…leads to questions of therapeutic uses of glycoalkaloids due to safety considerations. However, it is difficult to translate the results of an in vivo trial in vitro. Therefore, both animal and human experiments are essential to confirm or disprove the in vivo data observed in these studies.”  [Milner 2011].

Health Risks of Nightshade Glycoalkaloids

  • Glycoalkaloids destroy cell membranes. Research has shown that glycoalkaloids can burst open the membranes of red blood cells and mitochondria (our cells’ energy generators).

    “Some scientists have wondered whether glycoalkaloids could be one potential cause for “leaky gut” syndromes due to their ability to poke holes in cells: “…glycoalkaloids, normally available while eating potatoes, embed themselves and disrupt epithelial barrier integrity in a dose-dependent fashion in both cell culture models and in sheets of mammalian intestine…animals with the genetic predisposition to develop IBD, demonstrated a greater degree of small intestinal epithelial barrier disruption and inflammation when their epithelium was exposed to the potato glycoalkaloids chaconine and solanine.”

  • Glycoalkaloids cause birth defects in laboratory animals.

Nightshades and Mental Health

Centuries ago, the common eggplant was referred to as “mad apple” due to belief that eating it regularly would cause mental illness.

Due to widespread pro-plant food bias, the vast majority of scientific studies of nightshades explore their potential benefits rather than their downsides, so we do not have the studies we wish to have about how these interesting foods affect our well-being.

However, there have been plenty of documented cases of nightshade toxicity that demonstrate to us how poisonous they can be to our central nervous system, capable of causing severe neuropsychiatric side effects in human beings:

“In cases of mild glycoalkaloid poisoning symptoms include headache, vomiting, and diarrhea. Neurological symptoms were also reported, including apathy, restlessness, drowsiness, mental confusion, rambling, incoherence, stupor, hallucinations, dizziness, trembling, and visual disturbances.”[Milner SE 2011]

In a group of children who suffered from solanine poisoning as a result of eating potatoes that had been in storage for too long, severe psychiatric side effects were observed:

“The largest series of solanine poisoning involved an English day school where 78 schoolboys developed diarrhea and vomiting after eating potatoes stored since the summer term. Symptoms began 7-19 hours after ingestion with vomiting, diarrhea, anorexia, and malaise. Of the 78 boys, 17 were admitted to the hospital. Other symptoms included fever (88%), altered mental status (drowsiness, confusion, delirium) (82%), restlessness (47%), headache (29%), and hallucinations (23%). Three boys were seriously ill with hypotension, tachycardia, and stupor out of proportion to fluid and electrolyte imbalance. These boys were discharged 6-11 days after admission, and they had nonspecific symptoms and visual blurring for several weeks after release from the hospital.” [Barceloux DG 2009]

Keep in mind that these reactions just happened to be recorded due to their severity. We have no documented information about how everyday consumption of nightshades affects sensitive individuals, only numerous on-line personal accounts of mental health problems such as anxiety, panic, and insomnia that were alleviated by removal of nightshades from the diet. I personally experience profound insomnia and mild panic symptoms when I eat nightshades, which makes sense because glycoalkaloids overstimulate the nervous system.

If you experience anxiety or insomnia and are curious to know more about nightshades and the other foods most likely to be contributing to your symptoms, I recommend you read my Psychology Today article5 Foods Proven to Cause Anxiety and Insomnia.”

Fruits vs vegetables:  here we go again!

Those of you who are familiar with my philosophy about plant foods know that I believe vegetables are far less trustworthy when it comes to our health than edible fruits, and nightshades make this point nicely.  [Watch my Ancestral Health Symposium video about vegetables vs. fruits if you are curious about my vegetable philosophy.]

As you will see below, even though nightshade fruits contain glycoalkaloids, they either contain lower amounts of these potentially toxic compounds or contain gentler versions of them.

Luckily, most of the edible nightshades–eggplant, tomatoes, goji and peppers– are fruits (fruits by definition contain seeds). Tobacco is a nightshade vegetable, but it is typically smoked, not eaten, so the only nightshade vegetable humans consume is the beloved potato.

Potato Glycoalkaloids 


All potatoes are nightshades except for sweet potatoes and yams.

Potato plants make two glycoalkaloids:  alpha-chaconine and alpha-solanine.  These are the most toxic glycoalkaloids found in the edible nightshade family.  Alpha-chaconine is actually more potent than alpha-solanine, but solanine has been studied much more thoroughly, and is therefore more familiar.

There are numerous cases of livestock deaths from eating raw potatoes, potato berries, and potato leaves, but people don’t eat these things. However, there are well-documented reports of people getting glycoalkaloid poisoning from potatoes, typically from eating improperly stored, green, or sprouting potatoes.  At low doses, humans can experience gastrointestinal symptoms, such as vomiting and diarrhea. At higher doses, much more serious symptoms can occur, including fever, low blood pressure, confusion, and other neurological problems. At very high doses, glycoalkaloids are fatal.

Another reason why many people may not be bothered by potatoes is that glycoalkaloids are very poorly absorbed by the gastrointestinal tract, so, if you have a healthy digestive tract, most of the glycoalkaloid won’t make it into your bloodstream.  However, if you eat potatoes every day, levels can build up over time and accumulate in the body’s tissues and organs, because it takes many days for them to be cleared.  Also, since glycoalkaloids have the ability to burst cells open, they can theoretically cause damage to the cells that line your digestive system as they are passing through (this has been proven in animal studies but there are no human studies, to my knowledge).

Due to known toxicity, the FDA limits the glycoalkaloid content in potatoes to a maximum of 200 mg/kg potatoes (91 mg per pound). Human studies show that doses as low as 1 mg glycoalkaloid per kg body weight can be toxic, and that doses as low as 3 mg/kg can be fatal. This means that, if you weigh 150 lbs, then doses as low as 68 mg could be toxic, and doses as low as 202 mg could be fatal.

Glycoalkaloid levels of a few prepared potato products are available [Milner 2006]:

  • Potato chips, 1 oz bag:   0.36 to 0.88 mg chaconine and 0.29 to 1.4 mg solanine. Total glycoalkaloid concentrations range from 2.7 to 12.4 mg per bag.
  • Fried potato skins, 4 oz:   4.4 to 13.6 mg chaconine and 2.0 to 9.5 mg solanine.  Total glycoalkaloid concentrations range from 6.4 to 23.1 mg per 4 oz serving.

Potato Processing 101 

The vast majority of glycoalkaloid is in the potato skin, so peeling will remove virtually all of it. Glycoalkaloid levels can be dangerously high in unripe and sprouting potatoes; any greenish areas or “eyes” should be removed or avoided.

Glycoalkaloids survive most types of cooking and processing. In fact, deep frying will increase levels if the oil isn’t changed frequently, so fried products such as potato skins and french fries can contain relatively high amounts:

“Mechanical damage to potato tissue increases the concentration of glycoalkaloids available for consumption. In addition, frying potatoes at high temperatures does not inactivate but instead serves to preserve and concentrate glycoalkaloids within the potato, leaving them available for ingestion and delivery to the intestine…” [Patel 2002]

  • Boiling—reduces glycoalkaloids by a few percentage points
  • Microwaving—reduces glycoalkaloids by 15%
  • Deep frying at 150C (300F)—no effect (McDonald’s uses 340F degree oil)
  • Deep frying at 210C (410F)—reduces glycoalkaloid content by 40%

Tomato Glycoalkaloids

tomato glycoalkaloids

Tomato nightshades include all types of tomatoes:  cherry tomatoes, green tomatoes, yellow tomatoes and ripe red tomatoes.

Tomatoes produce two glycoalkaloids:  alpha-tomatine and dehydrotomatine. The majority is in the form of alpha-tomatine, so we’ll focus on that one here.

As tomatoes ripen, alpha-tomatine levels drop dramatically, from about 500 mg/kg in green tomatoes to about 5 mg/kg in ripe red tomatoes, or 2.3 mg/lb.  [For those of you keeping score at home—that’s Fruits: 1, Veggies: 0.] Artificially ripened fruits may contain higher amounts than sun-ripened fruits.

Tomato glycoalkaloids are about 20 times less toxic than potato glycoalkaloids. (Fruits: 2, Veggies: 0).  There are no dosage studies of tomatine in humans, but studies in mice tell us that 500 mg tomatine per 1 kg body weight (or 227 mg per pound) is the median lethal dose (“LD50”). This doesn’t tell us how much it would take to kill a 150 lb person; it only tells us that it would take 34 grams of tomatine to kill a 150-pound mouse. Since ripe tomatoes contain 5 mg/kg or 2.3 mg/lb of tomatine, it would take nearly 15,000 pounds of tomatoes to kill this Mighty Mouse (probably many fewer pounds if you were to simply hurl them in his general direction from across the room). Since green tomatoes contain 100 times more tomatine, it would only take 150 pounds of green tomatoes to kill the overgrown rodent.  We do not understand the effect of low doses of tomatine over time on any type of animal, including humans.

Eggplant Glycoalkaloids

eggplant is a nightshade

Centuries ago, the common eggplant was referred to as “mad apple” due to belief that eating it regularly would cause mental illness. Eggplants produce two glycoalkaloids:  alpha-solamargine and alpha-solasonine. Solamargine is more potent than solasonine.

Whereas potato glycoalkaloids are located mainly in the skin, in eggplants, glycoalkaloids are found primarily within the seeds and flesh; the peel contains negligible amounts.

The common eggplant (solanum melongena) contains 10-20 mg of glycoalkaloid per kg (or 4.5 to 9 mg per pound of eggplant).  Eggplant glycoalkaloids are considered relatively nontoxic compared to potato glycoalkaloids (Fruits: 3, Veggies: 0).

The median lethal dose (LD50) in rodents is 1.75 mg/kg.  This means that it would take at least 13 pounds of eggplant to kill a 150 lb monster mouse.  [Note to self—when facing a giant rodent in a dark alley, go for the eggplants, not the tomatoes].


Red and green bell peppers contain less than 10 mg of glycoalkaloid per kg. This is a very small amount, so if you react badly to peppers, you are either very sensitive, or you are responding to other compounds within the peppers, such as the notoriously hot and spicy capsaicinoids. 

What about Goji Berries?

Your guess is as good as mine…I could not locate any scientific information about glycoalkaloids in these foods.

Nightshades and Nicotine 

Nightshade foods also contain small amounts of nicotine, especially when unripe.  Nicotine is much higher in tobacco leaves, of course. Scientists think that nicotine is a natural plant pesticide, although it is unclear exactly how it works to protect plants from invaders. The amount of nicotine in ripe nightshade foods ranges from 2 to 7 micrograms per kg of food. Nicotine is heat-stable, therefore, it is found in prepared foods such as ketchup and French fries. The health effects of these small doses is not known, but some scientists wonder whether the nicotine content of these foods is why some people describe feeling addicted to them. In my opinion, it is more likely that the high carbohydrate content of those foods is responsible for their addictive properties.

Do you have nightshade sensitivity? 

As with any food sensitivity, the only way to find out is to remove nightshades from your diet for a couple of weeks or so to see if you feel better.  There are ZERO scientific articles about nightshade sensitivity, chronic pain, or arthritis in the literature, however, the internet is full of anecdotal reports of people who have found that nightshades aggravate arthritis, fibromyalgia, or other chronic pain syndromes. I am personally very sensitive to nightshades; they cause me a variety of symptoms, most notably heartburn, difficulty concentrating, pounding heart, muscle/nerve/joint pain, and profound insomnia. Everyone is different, so as always, you’ll need to discover for yourself whether these foods may pose problems for your individual chemistry. However, given what we know about nightshade chemicals, common sense tells us that these foods are well worth exploring as potential culprits in pain syndromes, gastrointestinal syndromes, and neurologic/psychiatric symptoms.

Recommended Nightshade-Free Cookbooks

Since nightshades in various forms find their way into so many familiar dishes, it can be daunting to know where to begin when first trying to cook without them. While there are many nightshade-free cookbooks on the market, these two stand head and shoulders above the rest because they both focus on whole foods recipes free of other common food culprits.

The Healing Kitchen book cover The Healing Kitchen: 175+ Quick & Easy Paleo Recipes to Help You Thrive is co-authored by the fabulous Sarah Ballantyne (aka PaleoMom) who has an impressive PhD in medical biophysics. This cookbook eliminates nightshades, grains, legumes, nuts, seeds, eggs, and dairy. In addition to delicious recipes, the authors do a beautiful job of explaining the science behind healthy eating, encouraging you to stay positive by focusing on what you CAN eat.

The Autoimmune Paleo Cookbook book coverThe Autoimmune Paleo Cookbook: An Allergen-Free Approach to Managing Chronic Illness is written by nutritional therapist/cook Mickey Trescott.  This beautiful and supportive cookbook includes helpful meal and shopping plans. All recipes are free of nightshades, grains, legumes, nuts, seeds, eggs, and dairy. Quite a few recipes rely on coconut and garlic, so if you have sensitivities to these foods, it may not be the one for you, but otherwise it’s a wonderful choice.

Other Food Sensitivity Syndromes

If nightshades aren’t your problem, you may be interested to know that there are many other foods which can cause real health issues for people.

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Barceloux DG 2009. Potatoes, tomatoes, and solanine toxicity. Dis Mon 55(6):391-402.

Friedman M. Tomato glycoalkaloids: role in the plant and in the diet. J Agric Food Chem2002; 50:5751-5780.  UDSA, Albany California.

Hansen AA.  Two fatal cases of potato poisoning.  Science 1925; 61(1578): 340-341.

Jones PG and Fenwick GR 1981. The glycoalkaloid content of some edible solanaceous fruits and potato products. Journal of the Science of Food and Agriculture 32(4):419-421.

Korpan YI et al.  Potato glycoalkaloids: true safety or false sense of security?  Trends in Biotechnology 2004; 22(3): 147-151. 

McMillan M and Thompson JC.  An outbreak of suspected solanine poisoning in schoolboys: examinations of criteria of solanine poisoning.  Q J Med 1979; 48(190): 227-243. 

Mensinga TT et al.  Potato glycoalkaloids and adverse effects in humans: an ascending dose study. Regulatory Toxicology and Pharmacology 2005;41: 66-72.  University of Utrecht, The Netherlands.

Milner SE et al.  Bioactivities of glycoalkaloids and their aglycones from Solanum species. J Agric Food Chem 2011; 59: 3454–3484. University College, Cork Ireland.

Patel B et al.  Potato glycoalkaloids adversely affect intestinal permeability and aggravate inflammatory bowel disease.  Inflammatory Bowel Diseases 2002; 8 (5): 340-346.

Sanchez-Mata MC et al.  r-Solasonine and r-Solamargine Contents of Gboma (Solanum macrocarpon L.) and Scarlet (Solanum aethiopicum L.) Eggplants J Agric Food Chem 2010; 58: 5502–5508.

Siegmund B et al.  Determination of the nicotine content of various edible nightshades (Solanaceae) and their products and estimation of the associated dietary nicotine intake.  J Agric Food Chem 1999;47: 3113−3120.

Please note that after 30 days, Dr. Ede may not personally respond to comments, however comments shall remain open to encourage community discussion.
  • Paleobird

    Very interesting article, Dr. Ede.

    You mentioned the association between nightshades and neurological issues in general. I was wondering if you knew of any research specific to epilepsy, (something I am very interested in because I have it).

    • Hi Paleobird,

      Interesting question…as is the case with so many food-health questions, I am not aware of any scientific information available about the possible connection between epilepsy and nightshades. However, given the fact that glycoalkaloids are toxic to cells in general, and nerve cells in particular, it would make sense that nightshades could be a culprit. The only way to know if nightshades are a factor in your seizures is to remove them from your diet for a while to see if you feel any better. With seizures it may be more challenging to notice, particularly if you are taking an anticonvulsant medication. If you are taking medication, and you decide you want to do a nightshade-free trial, you would want to have your neurologist monitor your progress with you.

      It can be challenging to remove nightshades, since potato starch is in many processed foods, and peppers/pepper extracts are in almost all savory prepared foods these days, in the form of chili flakes, cayenne, or paprika, and are often not even listed as an ingredient other than “spices.”

      The only dietary intervention I’m aware of for epilepsy that has scientific research behind it is the ketogenic diet (see bipolar/low-carb post).


    • JaylyandJennifer Jackson

      Very interesting comment. I ate eggplant for the first time a week ago, and suffered from a seizure overnight/early the next morning (awakened from sleep). I believe it was the eggplant that caused the seizure.

    • John T

      I’m genetically allergic to Nightshades. It runs in my family I’ve just figured out. Just so happens my Mother was an epileptic and they could never find the cause. When I was eating red tomato sauces I started experiencing blackouts and memory loss. It was terrifying. I also started stuttering and developed insomnia. Yes. The effects on the brain are severe.

      • Hi again John!

        How interesting (and tragic) to consider that your mother may have suffered seizures due to nightshades. It is known that glycoalkaloids do cross the blood-brain barrier and can accumulate in the brain.

  • Steve Parker, M.D.

    I appreciate this summary, Dr. Ede. I reviewed potential potato toxicity recently when I was deciding whether to include them in my personal version of the paleo diet (they’re included). I attempt to keep up with the internal medicine and medical nutrition literature, and, like you, I don’t see a lot on nightshade toxicity.

    • Hi Dr. Parker, and thanks so much for reading and commenting on this article–for those of you who haven’t visited Dr. Parker’s blog, it is at and contains lots of excellent information about Paleo diets. He pays special attention to the application of Paleo diets to the treatment of diabetes.


  • It’s interesting that you make the statement that the vegetable nightshade is more likely to harm us than the fruit ones, when most people I know tolerate potatoes far better than any other nightshade. Some react strongest to tomatoes, others to eggplant and I react really strongly to pepper spices, which you say don’t have glycoalkaloids. Whatever capsacain is, it does a number of me! (Rheumatoid Arthritis)

    • Right you are, Eileen–just because the research tells us that potato (skins) contain the highest amounts of the most potent glycoalkaloids does not mean that we can’t as individuals have our own unique reactions to nightshades. I personally am unable to tolerate all nightshades, with the peppers and eggplant being the worst for me and potato being the least bothersome. I never tried eating a pile of potato skins, though (the flesh of the potato doesn’t have any glycoalkaloids in it, which may be why most tolerate them so well).

      There are also likely numerous other naturally occurring chemicals in these plants that bother some of us and are simply not investigated by scientists. As you have already discovered, the best way to know whether or not a food bothers you is to listen to your body and believe what it is telling you:) I will write about the capsaicinoids in peppers in a future blog post.

      • Michelle Young

        lol and I used to think I was doing a better thing by leaving skins on when cooking potatoes…

        • peasporridgehot

          I think we all did!

        • Jennifer Smith

          I remember my mom always telling me to eat the skin of my baked potato, because that was “where all the vitamins are”.

        • John.

          Interesting discussion. I love tomatoes and bought a litre of tomatoe juice from the supermarket 3days ago. Today I’ve got the worst arthritis in every joint. I’m giving up these nightshades immediately to see if it makes any difference.

          • Michelle Young

            Dad tells me (as a severe arthritis sufferer) that he’s read he’s supposed to avoid tomatoes (but.. he wont… loves them lol)

      • keri

        wait. confused i am. I just read, “The vast majority of glycoalkaloid is in the potato skin, so peeling will remove virtually all of it.” But then you said right here, “the flesh of the potato doesn’t have any glycoalkaloids in it, which may be why most tolerate them so well.” Am i incorrect that skin and flesh are the same thing?

        • keri

          Ha! Well color me embarrassed. I am incorrect about skin and flesh being the same. Apologies. and i’m really enjoying/learning a lot from your blog about nightshades. I’m trying to figure out if i need to avoid them. Also, our garden got a virus called either tomato mosaic or tobacco mosaic virus which affected all of our nightshades growing. Do you know anything about that?

        • Cassandra Biophilia

          I can see why you thought that; flesh-colored crayons are the color of skin, not the stuff under the skin:-) But, when talking about plants, it’s different for some reason.

      • crosswind

        Potatoes are also High on *Oxalate* , Fyi in case they still bother you. Also tomatoes are High in *Histamine & *Oxalate

  • pone

    How are the toxins being removed from potato starch? Are you aware that there is now a health craze going on in the Paleo diet community to mix up to four tablespoons of raw potato starch in water each night and swallow it raw with no cooking? I wonder what kind of toxin levels that would expose people to, and is there any preparation that would remove the toxin?

    • Hi pone

      Interesting…I was not aware of this interesting trend, but luckily the vast majority of potential toxins are in the skin of the potato rather than in the flesh, from which the starch is made.

    • Tony McGarry

      This surprises me, as potato is excluded in the Paleo diet, or I should say “true” Paleo diet. Many people take what they want from the Paleo system ( a much better word ) and butcher it completely to suit themselves usually due to laziness or a particular food addition.

      The full true benefit of the Paleo system is seen when you take the whole system into account. The Paleo diet should be renamed to something like the Scientific diet or Nutrient Analysis diet. Very little of it is founded from the actual diet of Paleolithic humans but from the analysis of foods and food interactions. People who simply eliminate gluten and claim to be Paleo are kidding themselves. And restaurants offering Paleo (gluten free) menus are mostly after your money, with no appreciation of what Paleo is offering.

  • Vanessa

    Interesting read. Through a very long and frustrating process we realised nightshade is the cause of my daughters severe eczema. We have removed it from her diet and within 2 weeks she just had dry skin and within a month it was completely gone. I also realised it was the cause of many years of stomach cramps.

    • Caroline

      I too ended 23 years of living with often severe psoriasis by cutting out night shades and following additional nutritional advice tested and published by Dr John Pagano in his book Healing Psoriasis: The Natural Alternative.

      • Monica Popa

        Hello, from where can i have this book, because i live in Europe, Romania, and it’s not available anywhere:( Could you help with some ideas, please? Thank you.

    • Hi Vanessa

      That’s wonderful–congratulations for figuring it out and telling us about it!

    • Jane Vitek-Dixon

      So happy for your daughters. Hope they are still doing well. Coming from Europe to the US at age 6, we lived on potatoes and ‘all the old world fare’. It is great to have more information now a days. In my case the eczema went away at age 20 and other muscle and nerve issues arouse. Eliminating nightshade eased these symptoms. I learned about these things just a year ago at age 50.

  • bob

    is mairajana a nightshade like tobacco

    • Hi bob

      No, marijuana does not belong to the nightshade family.

      • anon


        • Ohmy Shrunkenhead


  • Christy

    Very interesting! This is a great article–thank you! Have you happened to look up any more on the peppers? I am doing an elimination diet and closing in on the culprit of some restless leg and fidgety symptoms. Nightshades for sure (or pesticides found on them–I will know more if I can isolate it down to organics only)–and I think perhaps peppers specifically–which makes me sad because I love spicy food.

  • Bobby Stranger

    I find tomatoes give me a nasty headache afterwards, Also, potatoes (esp. mashed) causes majir issues with excess stomach acid/heartburn! Rum old stuff, eh?!

  • BM

    I was diagnosed with osteoarthritis in my spine 5-6 years ago. Especially painful in the morning. I was so depressed trying to cope with this disease. On May 17 I read an article about nightshades and decided I would omit them from my diet for 3 months to see if it would help me. In 3 weeks 85-90% of the pain was gone! It’s been only 2 months and I’m still afraid that I will wake up and find it was only a dream.

    • Ohmy Shrunkenhead

      Very glad to hear it- I hope you’ve found continued relief.

  • Al

    Thanks for this article. I have been suffering from neuralgia for a number of years and spent a good few months without nightshades. I have just reintroduced them for one week and have seen certain aspects of the pain shoot up again. If I do suffer from nightshade intolerance, how long does the system need to eliminate them? Is there anything one can do to speed up the process?

    Have you ever heard of a link between nerve pain and the nightshade family? My pain doc wants me to see a micronutritionist, but I’m sure myself.

    Thanks again,

    • joe egbert

      Al , I had an outbreak of Shingles 6/2013 , it developed into Post Herpetic Neuralgia above Left Eye going towards back of skull , left side , upper branch of Trigeminal Nerve T5 ( absolute HORROR ) to this day it is still active . Lyrica , Gabepentin merely ” confused ” the nerve cells from Pain at times but Side Effects were HORROR , falling down , aggressive , agitated abnormal behavior along with thoughts ( Lyrica in my opinion out to be ” pulled ” ) avoid that one if possible I weaned myself off it slowly ( back to ” normal ” Thank God ) , as for POTATOES and Tomato Sauce , Bread Crumbs ( they in some cases contain POTATO STARCH ) . Last night’s supper was 1 flounder Filet Broiled w/ Garlic powder along with Bread crumbs & a bit of Margarine on top , along w/ 3 steamed veggies and the ” Deadly Potato ” , woke @ 2 a.m. & 3:30 to remove ice bag ( nerve soother ) , that was 2 times in a row POTATO caused Horrible Nights , I just threw them in the garbage , I’ll stick w/ my Yams / Rice and Green Tea .

  • Kristin

    Nice article! Lifetime headache sufferer who has tried everything imaginable to eliminate headaches. It’s early yet, but I’m seeing some pretty solid results from a diet that excludes nightshades. After a few weeks I plan to reintroduce them in a controlled way to see if I can reproduce the headache problems. Really enjoying the good times for now tho!

  • YK

    My daughter as a baby would get burning red cheeks…no other symptoms. It took a year for us to figure out that night shades where the culprit. We removed them from her diet and mine and redness disappeared overnight. Tomatoes were not a problem.

  • Bridgette

    I recently figured out that I have reactions to nightshades. My right shoulder would hurt after certain meals, I would wake up hurting all over, and/or my hands and feet would swell. I started keeping track of what I was eating and figured out the symptoms would happen after eating potatoes and tomatoes. I have stopped eating them and symptoms would go away.
    A couple of weeks ago, I went to a birthday and they had gluten free pie. The next morning I hurt. I looked up the ingredients for gluten-free bisquick, potato starch! I have to get more diligent!

  • Karen Ung

    I’m trying to get to the bottom to my sudden onset pain an fatigue, and diet is definitely a large part of the puzzle. Cutting out gluten helped, but I still felt bad, so I later cut out dairy, corn, and coffee. Bloating and digestive symptoms are pretty much gone, but I get really bad muscle and joint pain that comes and goes. I avoided nightshades for a month, felt almost pain free, and recently tried them again for 3 days in a row and WOW, my body is aching! Will stop the nightshades and stick with sweet potatoes and plantains. Was never a fan of peppers or eggplant (maybe my body knew these things were hurting me?), but tomatoes are hard to give up because I love pasta so much. Gotta do what we gotta do, right? Thanks for this – very interesting and helpful.

  • naser

    Ur reseach.. is very thorough!

  • naser

    Hope u do..more..such..researchs..!

  • Jwalker

    I have been suffering from what was thought to be autoimmune induced idiosyncratic hives for the last year. I have been tested for everything and had already eliminated eggs, wheat, dairy and beef from my diet and was on high doses of several allergy meds as well as xolair injections with no success. About a month ago after talking with my ND and doing some research online I decided to give up nightshades as well-by far my favorite foods-and lo and behold, no hives since I have stopped eating them. AND, I was able to start cutting back on the allergy meds I was taking. It’s extremely hard to avoid them-especially with everything else I can’t eat, but it does seem to be working. Thank you for this article to help affirm my choice!

  • Jodie

    It is easy for menopausal or perimenopausal women to confuse hormonal issues with nightshade symptoms. I was convinced the aches, Insomnia and fatigue were age related, but turns out it was an allergy.

  • Tracey Davidson Mizell

    I’ve suffered my entire life from ichthyosis and eczema. And after reading some Paleo books that mentioned nightshades, I eliminated them from my diet. Eczema gone! Ichthyosis is manageable (the Vitamin D supplementation appears to be helping too). And whenever I eat nightshades, my large joints (shoulders, hips, knees) hurt so bad and my throat hurts. My mother said as a child I always complained that “my bones and throat hurting” but of course, doctors dismissed it since they could not ever find a cause.

    My strongest reaction is to peppers and their dried spices. And since I live in Southern Louisiana where everything is cooked with these things, its been a difficult road, but I’ve learned to adapt.

    Another interesting thing about my body that seems to be “fixed” now that I’m eating gluten free (wheat allergy) and nightshade free is my body’s tendency to overheat quickly. Been an issue my entire life. But now it seems to be regulating better and I don’t pass out walking across the yard in the middle of summer.

  • tracey

    “Nightshades of all types were considered inedible prior to the 1800’s” – what a totally and completely false statement – people have been easting many nightshades (esp potato and tomato) for thousands of years before the 1800s

    • John Bowman

      in Europe.

  • Jenny L Porter

    Hello. Well written nightshade article. Just want to note for you that UT at Knoxville did an exclusive national conference a few years back on nightshade research by scientists. You might be interested to understand they are making strides in this area linking disease. Take a gander at your hospital Heart Association Research patient pamphlets when you have time and follow through on their research to get started. Nightshade destroys every cell it comes into contact with in my opinion. Happy hunting.

    • Ellen

      Wow!.. What a crime drama this is turning into.
      “Nightshades destroy every cell it comes in contact with…”
      should we call the FBI or the CIA. Sounds like a serial killer.
      Lately everything I thought was good for me wants me dead.
      Could this be true? If so, I am feeling very anxious and overwhelmed.

  • Ellen

    Because you have provided us with the facts I now understand more. I have RA and I will now learn to avoid Nightshades and see if there will be any improvement in my condition. I know will miss eating the food listed but I will try to keep the path. MAYBE SOMEONE CAN TELL ME WHAT IS GOOD FOR ME ???

    • SNAmien

      Firstly. Yes, definitively cut the nightshades for a while. I’ve been experimenting with diets for a while, and I’m really on the way to a good health. I got rid of hypothyroidism only by avoiding Nighshades (I’ve eaten some potatoes again the last months though) and possibly by limiting dairy and calcium (yes, you heard right). I’m also on the verge of getting rid of my IBS it seems (imbalanced gut flora seems to be a culprit for a lot of deceases).

      What I’m about to do, and have done for a little while to some degree is something like this; eat fats, starches and meat/protein one day. Maybe not eggs and dairy to begin with. Next day no fats, but vegetables and fruits, maybe some pure starchy food (maybe you should even just stick to green peas and rice or something for a while, on these days). 4 or 5 days a week fats and proteins, three or two days no fat, but vegetables, fruits and carbs.
      Keep to a couple of fats to begin with (like butter and sunflower oil for instance), and eat fat fish or take some omega 3s. Stay away from canola oil for now (I found out this oil really makes my digestion poorer) and be aware that you could be intolerant even to “healthy” oils and fruits and vegetables.
      This is a food plan that aims to make your gut flora rebalanced and to make it easy to figure out what you can and can’t eat in the future.
      I’m just a guy, doing my own research, but what I’ve finally discovered after some years of experience is that one shouldn’t start by eliminating just one thing, or counting on one kind of diet. It’s much easier in the long run to simply start by eliminating as much foods as possible and go from there, as long as you get the vitamins and minerals you need. For instance eating just meats, fat fish, rice and green peas will provide you with everything you need for a long time. I’ve yet to try such a strict diet for a longer time. Hope this will do the trick!

      • Ellen

        Thanks so very much for that answer. I was well written and understandable. I think I will try that fish and fish oil and peas and maybe not too much rice..
        Question what about oatmeal, yogurt, honey, dates walnuts???? People talk about superfoods. What do you think?

        • SNAmien

          You’re welcome. I just wanna help, but I’m not fully there yet myself, even though I’ve achived some major improvement.
          I don’t know about superfood, but I really don’t think it’s necessary to eat superfoods or supplement with a lot of stuff. I think the clue lies in how we eat, getting a good gut flora and thus absorb the nutrients in a proper way.

          Oatmeal is very nutritious, but again it’s about gut flora and proper digestion. For years I got serious bloating and stuff after eating any whole grain, but it’s much better now. Partly because I don’t eat tomato sauces, spicy pepper food etc anymore, I’m sure. But since I seem to be fine with moderate amounts of potatoes now, I think in my case it might have more to do with the digestive chaos that emerges from eating tomato sauces for instance, with meat or grain.

          I think it’s wise to separate the eating of fruits (and the nightshades are actually as much fruits as vegetables), and maybe some vegetables and the eating of fat and heavy foods. Fat and protein is good, but also very slow to digest. Thus I think most nutritious foods is good for you, if eaten in the right way. I would be careful with honey and of course sugar though. Think about it, sugars rarely exist in any significant amount in fatty, starchy or protein dense foods, unless we put it there.

          But DO try and avoid nighshades for a while. If you’re “lucky” this might be all you have to do. And keep in mind that when you eliminate something that’s bad for you, you might actually feel worse for a little while, because of withdrawal. At least with sugar. Maybe not with nightshades.

          • Ellen

            OK I’m on board…No more NIGHTSHHADES fro me for at least 3 months. I have already dropped bread so that is not a problem. My problem is I have a sweet tooth…have to work on that.

          • SNAmien

            I too have a sweet tooth:-) one of my challenges in the next weeks.

  • Monica

    I am severely sensitive to nightshades which manifest as muscle twitching, tremors and mild convulsions. It was only by accident that I figured out the culprit. This was 10 years ago and I wish this information had been available to me at that time. Thanks for writing this, it has made me feel less alone.

  • bowi dance

    I was wondering: what about courgette? I baked an entire one a few days ago for only a few minutes and I thought I was gonna die. That’s when I knew I had a problem with certain foods and not just the typical inflammatory dairy/chocolate/coffee, which I hardly eat. I had some lasagne last night and got severe diarrhea. Oh now I remember my mother also added courgette and probably tomato pieces to the sauce. And the white pasta of the lasagne is probably inflammatory just like white bread. Sigh. There aren’t many foods left that don’t make me insomnious, dizzy and nauseus…

    • Dear bowi dance

      I had to look up the word courgette and was pleasantly relieved to see you hadn’t consumed a sports car. Was the baked courgette (what I used to call zucchini but will now try to call courgette from time to time to keep things interesting) plain or did it have any other ingredients? If it was plain courgette let me know and I’ll see what I can find out about its composition for you.

      • Ohmy Shrunkenhead

        Isn’t zucchini somewhat goitrogenic?

        • Hello, Ohmy

          Not to the best of my knowledge…but just in case, I did a literature search in PubMed and found zero articles on the topic. If you know of a source that indicates otherwise, please feel free to share and we’ll take a look!

  • LJ

    Hi, great article. I took nightshades out of my diet aprox. 8 weeks ago in hopes that eliminating these foods will ease my fibromyalgia and osteoarthritis issues. I’ve been on a strict Paleo-type diet for 1.5 years, almost borderline Autoimmune Paleo Protocol, (no eggs, dairy). I was still consuming sauted or roasted red, yellow, orange bell peppers, hot pepper spices and tomatoes in a bloody mary type smoothie. My ND never said anything to me about nightshades possibly causing the inflammation issues. (No potatoes ever in diet or eggplants.) Has anyone that realized they were affected by nightshades also been exposed to 2nd-hand cigarette smoke at any time in their life? I was exposed to 2nd-hand cigarette smoke in my child-hood home for 18 years. I think there is a connection. I hated potatoes growing up and raw tomatoes. I believe being exposed to that poison cause my autoimmue system to constantly be in overdrive for so long and caused all my food intolerances, arthritis and fibromyalgia.

    • Hi LJ

      The possible connection between second-hand smoke and nightshade/food intolerances is very intriguing. I was exposed to second-hand smoke growing up, too, although I never had noticeable food intolerances until more than 20 years later. Interesting to think about.

      • LJ

        I think I had “food intolerances” while growing up but never knew what it was. I have had food issues my entire life. I was labeled a picky eater. I was borderline anorexic. I ate, but was very selective. I complained about dairy milk in high school that it tasted bad but no one would listen to me. I think I had dairy and gluten intolerance all this time. I am severely sensitive to cigarette smoke now, can’t be any where near someone smoking, it’s like claustophic, I simply can’t breath at all. I just found out a couple months ago that nightshades have nicotine in them. I think it’s all connected.

        • John T

          The connection is that Tobacco is also in the Nightshade family. Inhaling it is like poison to my system as well.

    • John T

      Right Here. I was born into an Italian family of heavy cigarette smokers, tomato sauce eaters and spicy food lovers. They also happen to be a family of chronically ill people who’ve all suffered through life with no medical treatment fixing it. But I was brought home from the hospital and became seriously ill. As I’ve heard it told I was taken to the hospital at 2 years old after prolonged periods of illness and I had to stay there for 2 weeks on an incubator. My digestion seemed to have shut down and I was withering. After 2 weeks I was allowed to go home as I recovered enough. But upon getting home I got instantly sick again because everyone was smoking in the house back then. Growing up my Dr’s would always look at my charts and say “You should NEVER smoke!” But they never said why. I think I have my answer better than they ever did. but it’s taken 46 years to figure it out.

      • Ohmy Shrunkenhead

        That intestinal motility problem is THE WORST. I prefer joint pain over a numb gut!

  • Jane Vitek-Dixon

    These posts are from last year but I must add to the comments. Couple years ago I started having unexplained muscle stiffness. Without any diagnosis from doctors and not accepting Fibromyalgia because that is just a syndrome I had recently had a 150 reactive panel test done. White Potatoes, scored way in the red followed by the other nightshade foods. I did not know what nightshade was so in my research I came across this information. Thank you so much. The way it was written and the contents all started making sense to my condition.

    • Dear Jane

      I’m so glad you found the article helpful and hope that your muscle stiffness gets better! If removing nightshades from your diet doesn’t help, don’t give up–there are plenty of other possibilities:)

    • John T

      It’s tough to make the NIghtshade connection because most people don’t see a relationship between Tomatoes, Potatoes and Peppers. I didn’t. And people argue it with me to this day. PEPPERS ARE NOT RELATED TO POTATOES!!! I just say… Look it up. Stop assuming you know everything.

    • pixiedust8

      I’ve been trying to see if you could just run sensitivity tests, so thank you! There seem to be so many possible food culprits that I’m just going to get this done instead of making myself miserable cutting out random things (especially since my muscle issues only arose recently, so I doubt I’m sensitive or allergic to that many things). I’m assuming an allergist does this?

      • Hello, pixidust8

        Yes, an allergist would be your best bet for all kinds of allergy and sensitivity testing. Best of luck!

      • Ohmy Shrunkenhead

        ALCAT testing is fairly good, and encompasses a wider range than the ELISA system. Professionals debate the reliability of IG reactivity for revealing sensitivities, but it’s definitely a start.

        • pixiedust8

          Thank you!

  • zach

    I have suffered from sensitivity to dairy and nightshades since I was a little boy. I never knew why until I was about 26 years old. I usually just put up with the pain and discomfort to be able to eat my favorite foods still. Around 28 I had to go on a heavy dose of antibiotics for about 7 months to treat an illness I had. After being on them for so long I noticed that the effects from the toxins had greatly intensified to the point that I have now had to eliminate them from my diet. Do you know of any studies for cures to this deficiency? Also have you heard of a correlation between antibiotics and food allergies? Thanks


    • Hi Zach

      Many people report new food sensitivities or worsening food sensitivities after taking a course of antibiotics, so you are not alone. I’ll be writing in more detail in the future about the theories behind what may cause food sensitivities but there are no definitive studies yet, as far as I know, but here is a report on a study conducted in mice that shows a connection between certain bacteria and food intolerances:

      • zach

        Thanks for responding I will read this for sure!

  • Cindy Holton

    For all of you who cut out the nightshade family but still get symptoms, have you checked your food for Maltodextrin, Dextrose and Dextrin (MDD), and your medications for Sodium Starch Gylcolate? Although they can all be made from any starch it is very often Potato! For those in the UK, Waitrose seem to specify the type of MDD they use i.e. Maize Dextrose. I only have to have an exceedingly small amount and I know about it for the next 4days!

    • John T

      Don’t forget “Modified Food Starch” as well. And if the list simply says “Spices” you can bet Paprika is in there. And Paprika is my most serious offender. I alos can’t take any tablet formed pills. Even Benedryl. They’re all bound with Potato starches. I get terrible stomach pains within 24 hours.

      • Jane Vitek-Dixon

        I thought Benedryl had corn. You guys know that in Canada, corn is on the top 15 allergens list. Here in the US it is hardly talked about. Just dairy and peanuts seem to be the issue here. I have never come across a conventional doctor who mention a possible reaction to nightshades either. Just give us the medicine and cover up the symptom but not find the cause.

        • Hi Jane

          Yes, corn is now recognized in the U.S. as one of the top 9 allergens: . The same foods that trigger true allergies can also trigger non-allergic food sensitivities, so even if a person tests negative for true allergy to corn, it doesn’t mean that the person doesn’t have a corn sensitivity. The only way to know for sure is to remove corn and corn products from the diet completely to see if the symptoms in question go away. It may require removing corn products for 2 weeks or more. Just as you say, most doctors, including allergy specialists, do not make the connection between food sensitivities and unexplained symptoms, sadly.

        • Ohmy Shrunkenhead

          Corn is a major economic staple here, along with wheat and potatoes. They make the country money, and pharmaceutical companies pay next to nothing for these cheap, heavily modified excipients. They are always contaminated with pesticide residue and mold aflatoxins.

    • Jane Vitek-Dixon

      These are also derivatives from corn. Also on my list of ‘better stay away’. It is sad that these do not specify the origin. I have emailed a few companies asking this question. Even sugar. Some ingredients do not specify what the sugar was made from. I bought a organic ‘healthy snack’ but the only thing I was not sure of was the sugar. I emailed the company and it was beet sugar. I am not suppose to have beets and was not sure if this would be a big deal for me. One must me their own advocate.

      • Maureen

        All I
        can say is thank god for the internet! I
        was diagnosed with Celiac Disease about 15 years back (all three of my kids
        have now been diagnosed as well). Changed my diet, felt great for several years,
        but then other issues arose. Over the past 2 years I’ve found great information
        about other foods that should be avoided if you have CD….sugar cane, rice,
        corn. Made the change, started to feel
        somewhat better, then another setback.
        Read about nightshades, removed from my diet, and within 2 weeks my
        joint/muscle aches were significantly reduced.
        I still have moments where it flares up and now know why, hidden amounts
        are in so many foods/over the counter medicines…..BIG SIGH!!. It’s exhausting but like you said, Jane, we
        have to be our own advocate. The medical
        world is still in the dark. Thanks to everyone for sharing their
        stories/findings, it’s given me hope : )

  • boville

    Does cooking tomatoes such as using them for tomato paste or pizza sauce reduce or eliminate the nightshade toxicity? How about the commercially sold paste or sauce bought?

    • Hello, Boville

      No, cooking doesn’t significantly reduce concentrations of glycoalkaloids or destroy them. Luckily, the one process that effectively reduces glycoalkaloid concentrations is ripening, so as long as the tomatoes used in sauces and commercially available pastes are very ripe, the levels should be minimal.

      • boville

        Thanx for your reply! That’s a huge load off of my mind. 🙂

    • John T

      Commercially sold pasta sauces also contain Paprika to give them that super rich red color. If it says “spices” on the ingredients list, you can bet it’s in there.

  • Lindam165

    I’m grateful for the article and to all those who posted. About 15 years ago I learned about the No Nightshades Diet proposed by Dr Childers. I purchased their cookbook and became a devoted Nightshade sleuth. The No Nightshades Diet works for me. Dining out has been my biggest challenge, though, so I’ve learned I’ll never “recover” from the effects Nightshades have on my body. My symptoms include arthritis, fibromylasia and nuroapathy. The intensity of symptoms depend on how much and which Nightshade I’ve consumed. Also, the slightest exposure to second-hand smoke triggers sinus infections, inflamation down the right side of my neck, and settles in my right shoulder. I am frustrated that second-hand smoke exposure occurs when I’m in public and its out of my control. If I can get past feeling embarasssed, I’m considering wearing a breathing mask when I’m in public. Anyway, thank you for this opportunity to share.

    • Jamie Mahaney

      Also include removing ALL grains from your diet for a week just to see how amazing of a difference you will feel…then keep them out so the fungus in your body/gut die off…grains (even gluten free products) are a fungus culprit which is shown to increase stuffy nose and aches and pains, to put it simply. Best of luck!

    • Ohmy Shrunkenhead

      Poster below is right- allergic reactions to grains (gliadin, gluten), roots and legumes (lectins, alkaloids) and their associated microbes (molds, yeasts) can cause the chronic hypersensitivity reactions that provoke various autoimmune conditions.

    • Ohmy Shrunkenhead

      I have lupus and some genetic conditions that encompass similar symptoms. I hope you find a consistent method to prevent pain that doesn’t overwhelm you.

  • yea…..i can certainly tell you i have severe sensitivity to nightshades and root veggies…glycoalkaloids especially. Tingling arms and legs, neurological issues, intestinal issues….its caused me significant physical and mental anguish over the past decade. This is a great article….outlines a lot of important information on nightshades…its amazing how much of this food is consumed by the US culture and I am sure elsewhere in the world…a lot of people have no clue what they are eating and how it effects the way they think, act and feel.

    • Well said! I certainly had no idea how foods like nightshades affect our bodies until, like you, I developed all kinds of mysterious symptoms that my own doctors couldn’t explain or help me with! Foods, especially plant foods, are fascinating.

  • John T

    Nightshade vegetables detroyed my life. I’m Italian and come from a family of people who love their pastas and sauces. I also come from a family of chronically ill people who’ve lived with various bizarre illnesses that have altered their lives beyond measure. When I was young I always noticed I got acne if I ate potatoes or tomatoes but as I got older it became much more serious and was impossible to track down as the delay in symptoms can be pretty long. But my GI tract has been rediculously inflamed and I had what resembled diabetes but Dr’s said wasnt. I would suddenly experience blinding stomach pains, distention and severe weight loss that nothing could stop for weeks at a time. As I got older it started to manifest as personality changes, iratability, memory loss, hair falling out, dry skin, mouth sores, anorexia, insomnia, disgusting body odor and the fact that my body did not grow as it normally should have (failure to thrive). The only way I tracked it down was looking at my family’s history with illness and the fact that my neice is now experienceing the same things and noticed her reactions came after eating tomato sauce. It’s no coincedence. It’s GENETIC. But potato is in everything from pill binders to breads and seasonings. Thanksgiving was a nightmare. I was severely ill as a child and after allergy testing they came back with “paprika” allergy. But they never looked at the entire Nightshade family as the culprit. My GI tract is so damaged at this point reparing it is a full time job. I have to avoid Potaoes, SWEET POTATOES, Eggplant, all Peppers (the kiss of death), PAPRIKA (made from peppers), Black Pepper, White Pepper (yep. No mistake. They absolutely trigger me), DR.PEPPER (Yep. makes my face swell up like I’ve been stung by bees), and I have to saty away from cigarette smoke. I moved to Va. in 2010 and became violently ill. I couldn’t get well and when pollen season arrived I became so ill I was housebound. Turns out it was from the feilds of tobacco plants surrounding where I lived. The pollen was like arsenic to my body. My sinuses became so inflamed I had to rinse them 4 times a day and plug them to keep them from getting more in them. This is very real and very life altering. Potato, Tomato and Paprika are used in so many things. No wonder my Mother cooked without spices and everything was bland. I made fun of it when I went out into the world but I guess the jokes on me. She knew more than I gave her credit for

    • Hi John

      What a terrible experience you’ve had with nightshades. Thank you for telling people about it here so that others can learn from it. I know Dr. Pepper contains many “flavorings”, one of which may be possibly be cherry in origin? I wonder if that may explain your reaction to Dr Pepper…And yes, I completely agree that nightshades are everywhere. It seems more and more common to find red spices like paprika and chili pepper flakes in everything from everyday side dishes to chips and chocolate. Very difficult to avoid in prepared foods in particular! I hope you are feeling well and healthy at this point.

  • Beth Chickering

    I don’t have any symptoms from any nightshade except Peppers, any variation. I used to just have bad heartburn but in the last year I started excessive burping for an hour or so to vomiting after I have burped. My aunt and my oldest son also have reactions but not as severe as me.

    • Hi Beth

      This may mean that your symptoms are due to a natural ingredient in peppers that does not exist in other nightshades. Capsaicin is likely, as peppers contain capsaicin (the ingredient responsible for the spiciness of peppers) but other nightshades do not. Peppers may not contain any glycoalkaloids at all, and glycoalkaloids are thought to be responsible for most symptoms of nightshade sensitivity in most people.

  • Chris Ann Roncone

    I could be wrong but it seems for me that white potatoes have much more negative effects than the other nightshade (skin or not). For those who have issues with nightshade and gluten make sure you are aware that most gluten-free baked goods are made with potato flour.

    • Hi Chris Ann

      How could you possibly be wrong about your own experience, I say! We are each so different in how we respond to plant foods and all the natural chemicals within them. It could be that something other than the glycoalkaloids in potatoes are bothering you or that you are especially sensitive to the type of glycoalkaloid found in potatoes. And yes, many gluten-free foods have potato lurking within! Thank you for your helpful comments.

    • Ohmy Shrunkenhead

      Yeah, sorghum is an issue for some, too. In my experience, specific food sensitivities (immune reaction or malabsorption of proteins) and nightshade sensitivity (alkaloid intolerance and overdose) both cause similar inflammation issues. In my case, offending proteins and alkaloids result in neuropathy (joint pain), while lectins and gliadin cause neuralgia (numbness). Both wreak havoc on all of my insides.

  • Peter Doedens

    There is confusion about the different families for black pepper and cayenne pepper.
    Black pepper is part of the Piperaceae family and cayenne peppers all species of Capsicum, a genus in the family Solanaceae.. I mean are there families inside families with these plant species?

    • Hi Peter,

      There aren’t different families within families, but there are different genera (plural of genus) within families. My understanding is:

      Black pepper: family Piperaceae, genus Piper
      Cayenne pepper: family Solanaceae, genus Capsicum
      Eggplant: family Solanaceae, genus Solanum
      Tomatoes: family Solanaceae, genus Lycopersicon
      Potatoes: family Solanaceae, genus Tuberosum

      Hope that clears it up!

  • Ohmy Shrunkenhead

    =D it really messes with Indian and Mediterranean food!

  • Ohmy Shrunkenhead

    It’s so sad to see everyone shooting in the dark to discover what’s wrong with them, or wrong with these foods. This blog post provides a very concise, informative explanation. Thank you for it. I wish more doctors took these biochemical reactions seriously, but it’s not really the way mainstream medicine is officially done now. The divide between research and practice is too wide.

    • Thanks, Ohmy. I completely agree that most doctors do not know about how food chemistry affects the body, and this can contribute to difficulty helping people who have food reactions. This is a topic that is not taught in medical school; unless you have a personal interest in it, you’re unlikely to come across information about it in the course of daily practice as a physician.

  • Nightshades also affect my HS

  • Interesting about peppers not containing as much glycoalkaloid as the other nightshade family foods. At a naturopathic clinic I visited in Frankfurt, Germany last month, they recommended that the people they treated ate a grain free, dairy free, sugar free and nightshade family foods free diet except peppers were not listed among the nightshades. I wondered why this was and now I know the answer.

    • Hooray for answers! Glad you found the article interesting. If you don’t feel better removing the grains, dairy, sugar and other nightshades (all of which are excellent recommendations, by the way) you may want to experiment with removing peppers to make sure they don’t bother you, but I hope that you are able to continue enjoying them!

      • I gave up gluten grains, dairy and sugar years ago and my gut was better for it. I gave up all grains more recently as I no longer tolerated them. I have to eat a low histamine food diet too so I don’t eat eggplant or tomatoes so the diet is not new to me. I like red peppers so I hope they are not affecting me but I might try cutting them out for a while as you suggest.

  • This link appears to be broken–if you have an updated link, please send it and I’d be happy to take a look!

  • Connie Yan

    This is a very thorough post about nightshades. Thank you for the information. Although this isn’t very scientific, I have an anecdote regarding Goji berries. I received a large bag of dried Goji’s from a relative about 4 years ago and since they are widely touted as a superfood, etc. etc. I proceeded to sprinkle them liberally on my morning muesli on a regular basis. I developed a case of scalp psoraisis which I battled on and off for the next 4 years. I never made the connection to the Goji berries… instead thinking it was caused by shampoos, dairy, stress, etc. I stopped consuming Goji’s about a year ago but my symptoms carried on, although less severe. I stopped using shampoo and my symptoms lessened considerably but still not “cured”. I live a very healthy lifestyle, exercise regularly, eat a mostly vegan diet, but the psoriasis would still not completely clear. Last month I cut out nightshades. I eat alot of potatoes, tomatoes, peppers, and I do like eggplant. Almost overnight my scalp cleared up. All I can say is damn those friggin’ Goji berries. Superfood my a#%!! Don’t eat’em!

  • Brutal.

  • Sky Price

    I’ve used belladonna (deadly nightshade) several yrs ago on occasion, while taking homeopathic supplements. I’ve had severe health issues, a majority the past 12+ years. Especially the past 11. I was also a smoker for several yrs n tobacco is a nightshade. I’ve read about how tomatoes n potatoes contain nicotine, n I have always felt sort of addicted to them, tomato in pizza sauce. Ironic how they contain nicotine n are 2 of the main staples in America. A few yrs ago, I took some Ashwaghanda root. Also a nightshade. A helpful herb sometimes but sometimes seems possibly dangerous, but since im already ill was unsure of sideeffects. I ate a green potato, after removing the spot n around it. Had heard that its fine that way, but they can accumulate more solanine. I think i had a worsening of illness that nite n came across the topic of nightshades. Possible the green potato n ashwaghanda root had a bad solanine reaction. I’ve been a million times healthier than I was before mid2012, but I still have health backslides n have still been chronically ill w severe pain constantly. Not nearly as excruciating as it was before mid2012 though, when I decided to go vegan. I was wondering, if someone ingested belladonna yrs ago on occasion, n was a smoker for over a decade off n on, would they be likely to be more sensitive to solanine? Probably best to stay off nightshades altogether?

  • Nightshades trigger my lungs big time. I’m asthmatic, and it took me a long time to figure it out. Why am I wheezing after eating a healthy salad? Ohhhh…. Tomatoes!!

  • Gina Bertarelli

    This information is very important and it’s being suppressed. Nightshades also are high in D3. I can’t take any D3 at all without feeling like I’m having a heart attack, and through this article I learned that it was nightshades that were making me sick. Thank You so much for sharing your work.

  • Gina Bertarelli
  • John W Smith

    I have extensive experience with arthritic patients and nightshades, including patients with psoriatic arthritis and rheumatoid arthritis. When placed on a plant based diet high in alkaline elements, these patients can almost always tolerate nightshade plants. Tomatoes seem to aggravate arthritis whose bodies are more acidic, that is, who eat a diet high in acid ash elements, usually from a high protein diet, and especially from animal proteins. These very same individuals suddenly can tolerate tomatoes, chilis, etc., with no aggravation of their symptoms if they change to a plant based diet.

  • Joseph Michael Giffen

    I am more intrested in the idea that tobacco has anti-cancer properties…. I mean that would undermine The idea that tobacco causes cancer.. Very interesting… So what is the fight against tobacco really about

  • Ally

    Hello, thank you for your work De Ede. I have heard, even was taught at school in history classes about how farmers throughout the history of agriculture spent an awefully lots of energy to breed out bitter taste and grew more sweetened fruits. As an adult now, these information went right above my head and completely forgotten until Someone retweeted one of articles and slowly I have come to recognise the adverse effects of some vegetables are very real. At the moment, I no longer eat brussell sprouts and some cruciferous, but strangely though, roasted aubergine seems to be agreeable to my body.

    Anyway, the reason I am writing to you is that I have a question on my mind for some time now and would really appreciate if you could give me your perspective.

    Is the artemisia genus harmful? Wormwood and mugwort are commonly being taken as tea, nearly all herbalists praise their effectiveness and their medicinal properties in particular the bitterness that is unique to this genus (except tarragon) which is believed to stimulate the production of bile and thus plays a role in helping the body to digest fat etc…


  • Michael D

    This is the most comphensive write-up of this interaction that I have seen. Thank you! Nightshades and apples both decimate my availabile energy. Although I do absolutely need to eat red beets as kind of an energy sustainer or blood builder. I am not sure why that is.

    My theory for the ‘addictive’ quality of nightshades is in the area of gut information and vagal response. Something with irritation following nightshade exposure. Or other irritants (gluten, msg) etc seems to stimulate an inflamed state of the gut/vagal nerve. The Vagus looks to be satiated…. The mind/body connection tries this with food. But vagal tone is really only ‘ soothed’ by being at peace and a restive state. This could also explain the anxiety response to a degree. It’s something I’ve written about a few times

    Michael Wallace

  • Adartse

    We planted Tomato on a farm backyard and have abundant big harvest.
    I gathered a kilo of ripe and unripe tomatoes and ate fresh about 3-4 big half green and half red tomatoes that evening, as salad, with pork and rice as main dinner.
    The following morning, i have 3 scrambled egg with 2 big semi-ripe tomatoes again as I like it for my scrambled egg.
    By noon, I boiled two big potatoes as lunch.
    That evening, i already felt some kind of slight pulsating pain on my sciatic nerve, from the pelvis down to the thighs.
    I have a soft, slight diarrhea stool that same evening and the following morning, I got a very painful ankle joint. I can barely stand on my left foot. I thought i hit my ankle on the bed steel support while asleep.
    I got this acute ankle joint for two days. The pain diminished after i took, Diclofenac and Ibuprofen.
    It was only the other night, that I found out about this SOLANINE in unripe tomato, after searching what could have caused my acute arthritic bout of left ankle.
    So there it goes.. Do not eat lots of raw/fresh semi-ripe ripe tomato.
    I may be just sensitive to Solanine, and other people may not. But still, take extra precaution.