Low-Carbohydrate Diets


Examples: Atkins®, Protein Power, LCHF, Ketogenic Diet, Rosedale Diet.  This strategy was made popular by Dr. Atkins but has been used by physicians for over a century to treat obesity, diabetes, and other health problems. Find out how it works and whether it is safe.

EXAMPLES: Atkins, Protein Power, LCHF, Ketogenic Diet, The Rosedale Diet

Very low carbohydrate (0 to 50 grams/day)

FOODS: All sweet and starchy foods are essentially forbidden.


Most effective diet for weight loss
Often eliminates cravings and food obsession
Energy may improve
Mood may improve
Reduces risk for numerous chronic diseases
Encourages fatty foods, which some people enjoy
May not need to count calories
Best diet for carbohydrate-sensitive people


Initiation can be difficult (carbohydrate withdrawal)
Socially challenging (can be hard to eat out)
There may be side effects, depending on food choices
Cheating once can set you back a few days or more
Some versions allow processed/artificial foods
Some people need to also limit calories to lose weight


Low-carbohydrate diets were made popular in recent decades by Dr. Atkins, but the concept has been around for more than a century.  It has long been known by scientists that very low-carbohydrate diets are effective not only as a weight loss strategy, but also as a way to treat and/or prevent diabetes, epilepsy, and other common chronic diseases caused by insulin resistance. To learn how to determine if you have insulin resistance, read my post: How to Diagnose, Prevent and Treat Insulin Resistance, where I include a downloadable PDF with medical tests you can discuss with you doctor.

Are low-carbohydrate diets safe?

There is plenty of strong scientific evidence now that low-carbohydrate diets are safe. How could the Inuit Eskimos have thrived for centuries eating an essentially carbohydrate-free diet if low-carbohydrate diets weren’t safe? The body requires zero grams of carbohydrate, so removing carbohydrate from your diet will not harm you.

However, if you take medication for any chronic health problem, especially if you use medications to control diabetes, high blood pressure, or heart disease, it is very important that you work with your health care provider in the early stages of this diet to monitor your medication dosages. This diet can have powerful (positive) effects on your chemistry, often very quickly. Blood pressure and blood sugar can naturally fall towards more normal values even within a few days, so medication dosages may need to be reduced accordingly to avoid potentially serious medication side effects.

Are low-carbohydrate diets effective?

Yes, they are in fact uniquely effective. Most people lose more body fat, faster, and more comfortably on low-carbohydrate diets than on any other diet tested. Low-carbohydrate diets are usually healthier than other diets, because they improve cholesterol profiles and blood sugar/insulin profiles much more than other diets do. This is because carbohydrates are the driving force behind cholesterol and blood sugar problems. These diets are absolutely the best diets for people with pre-diabetes and diabetes (type I and II), and for carbohydrate-sensitive people in general. These diets have the potential to completely reverse type II diabetes.

Ketogenic Diets

The ketogenic diet (as written about in books such as The Rosedale Diet, New Atkins for a New You, and The Art and Science of Low Carbohydrate Living) is unique in that it is not only very low in carbohydrate, but also limited in protein, so that the body has no choice but to burn fat for energy.  These specially-formulated low-carbohydrate diets have been successfully used to treat epilepsy for decades, and are more effective than anti-seizure medications in some cases. Researchers are even investigating the potential of low-carbohydrate diets in the treatment of cancer. I wrote about ketogenic diets and cancer in my post: Cancer Part III–Dietary Treatments. For a great personal story about my friend Anne’s experience with a ketogenic diet as compared to Weight Watchers, read my post: Ketosis Done Right—Meet Anne.

I frequently recommend very low carbohydrate diets to my patients who wish to treat mental health problems such as depression, anxiety, bipolar disorder, and eating disorders, without medications. In my post, Bipolar Disorder and Diet Part II: Low Carb Diets, I write about how ketogenic diets are being used in the treatment of epilepsy, bipolar disorder, and other brain disorders.

Low-carbohydrate induction phase

The first 24-72 hours on a very low-carbohydrate diet can be tough, as your body has to adjust to living without dietary sugars and starches. You may feel irritable, hungry, moody, and tired. You may have trouble sleeping. However, once you get through that initial withdrawal period, your body will be off the dreaded invisible insulin roller coaster and you should feel much better. It takes several weeks for your body to completely transition from decades of being a carb-burning machine to being what it was designed to be—a fat-burning machine—so if you try one of these diets, be sure to give it at least a month if you can, before you decide what you think of it.

Some low carbohydrate diet plans suggest that you gradually increase your carbohydrate intake after a certain period of time, or once you have achieved your weight loss goals, but this is not necessary, and is likely to backfire.

Can you gain weight on a low-carbohydrate diet?

YES. Some years ago, my mother lost 90 pounds effortlessly on the Atkins diet, whereas I myself gained 5 pounds. Everyone is different. No diet works perfectly for everyone straight out of the box. I have since learned how to tailor low-carbohydrate diets to suit my own chemistry. While many (lucky) people can eat anything they want on a low-carb diet and never have to count calories, protein grams, or fat grams, others of us are less fortunate. Some people DO need to count calories, although in most cases, you can get away with significantly more calories on a low-carbohydrate diet than you can on a standard low-calorie diet, because your metabolism is higher.

Can you eat sugar-free treats on low-carb diets?

Some people are capable of generating blood glucose and insulin spikes after eating sugar-free products, such as candies and cookies sweetened with sugar alcohols. After watching Dr. Andreas Eenfeldt’s excellent video presentation about his LCHF (“Low Carb High Fat”) diet, I was inspired to test my own blood glucose response to sugar-free chocolate and found that my blood sugar rose from 83 to 126 within less than an hour (and I am not diabetic). Therefore, you may need to avoid these kinds of treats in order to be successful.

Another important fact: whey protein is often recommended as a low-carbohydrate, low-glycemic index supplement on some versions of these diets, and Atkins even markets shakes made with whey protein. However, even though whey proteins don’t raise blood sugar, they do raise insulin levels substantially (see my dairy page), so you may need to be careful with these, because insulin spikes tell your body to make fat, not burn it.

Are low-carbohydrate diets healthy?

Removing carbohydrate from your diet is very healthy. However, like any diet plan, the overall health of this diet depends on your food choices. Healthy eating is not just about what you are not eating. It is also about what you are eating. I have known people who have found some very unhealthy ways of approaching a low-carbohydrate diet. There are plenty of low-carbohydrate junk foods on the market that are not good for your body.

Some low-carbohydrate plans allow you to include a variety of unhealthy foods, such as low-carbohydrate snack bars full of highly processed ingredients, ready-made sauces loaded with chemicals, and dessert substitutes made with artificial sweeteners. You can choose not to use them if you want to create a healthier version of this diet.  It is always best to choose whole foods whenever possible. 

Can vegetarians and vegans eat a low-carbohydrate diet?

Yes, absolutely, but it is more challenging. The reason for this is that many popular plant protein sources are quite high in starch—hummus (and beans of all types), tempeh, grains, nuts, and seeds contain significant amounts of carbohydrate. It’s not that you can’t eat these things at all, but you need to count their carbohydrates and make sure you’re not eating more than about 10-15 grams per meal.

Vegetarians can enjoy eggs and hard cheeses, but would need to limit quantities of certain dairy products, such as milk and yogurt, as they contain lactose, a naturally-occurring milk sugar.

Vegans are more limited still, as eggs and dairy products are off the menu, however, it is still possible if you are motivated, and you will reap all of the same health rewards that meat-eating low-carb dieters enjoy.

There are numerous vegetarian and vegan protein powders on the market. Options include casein, soy, pea, rice, and hemp protein powders.

Low-carbohydrate diet side effects

The most common side effects reported include constipation, fatigue, bad breath, and insomnia. These are typically not due to the lack of carbohydrate, but to the types of foods chosen and how those foods affect certain individuals. All of these can usually be corrected with special adaptations. I will be writing more in future articles and in my blog about special changes you can make to these diets if you are having trouble tolerating them.


Very low-carbohydrate diets are the best overall diet plans for weight loss, especially for those who are carbohydrate-sensitive. These diets are also very effective in the management of type I and type II diabetes.

Low carbohydrate diets stabilize insulin levels, and therefore I believe that these diets can also be used to successfully manage all kinds of other chronic health problems which are associated with hyperinsulinemia (high insulin levels).

Excellent resources and support for low-carbohydrate diets include:

Jimmy Moore’s Livin’ La Vida Low-Carb Blog and Podcast

Dr. Andreas Eenfeldt’s LCHF diet: www.dietdoctor.com

Drs. Michael and Mary Eades’ book Protein Power: The High-Protein/Low Carbohydrate Way to Lose Weight, Feel Fit, and Boost Your Health-in Just Weeks! and their website:  www.proteinpower.com

Dr Ron Rosedale’s book The Rosedale Diet and his website: www.drrosedale.com.

The best book about the science behind ketogenic diets is The Art and Science of Low Carbohydrate Living by Dr. Stephen Phinney and Dr. Jeff Volek. It is superb—thorough, authoritative, well-referenced, and readable. Drs. Phinney and Volek also co-authored The New Atkins for a New You, along with Dr. Eric Westman. This book is a true diet book, with practical advice, menu plans, etc.

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  • Hi Dr. Ede, do you have any recommendations for the constipation side effect of eating low-carb? Should I take magnesium? Thanks for your time!

  • Hi Elaine

    Constipation is not caused by a lack of carbohydrates but by the presence of specific foods that are causing constipation. I don’t know if you have already read my blog post on the topic, so if not, take a look at that. Two additions I would make to that list are raw and/or tough/fibrous vegetables, and gelatin. You can add seeds and grains to the culprit list, too, since they are in the same family as legumes and nuts. You may not need to eliminate all of these culprits; it may be that there is only one that is bothering you. Everyone is different.

    • Okay. So perhaps people eating low carb end up complaining about constipation because they are suddenly now eating an increased amount of (say) tough veggies with the new diet? There is gelatin in my fish oil supplement, so maybe I will see if that is the culprit, since I am hardly eating any vegetables. Thanks!

  • Sarah

    I was on a low carb mostly ketogenic diet for about a year and a half. I did lose weight, and at first some allergy type symptoms improved. My blood sugars were mostly reasonable. mostly below 140 if not 120. However, then things went downhill. I started to get more allergy sorts of symptoms. My insomnia became worse. My depressed moods which had never really improved, got worse. It was very distressing to put it mildly. Finally, I decided to try some starches which I had pretty much dropped from my diet. Things got maybe a little better. At least my constipation went away. I will have to say at that same time I eliminated most dairy, because I had determined that I must have histamine intolerance. I still think that or it’s a good imitation of histamine intolerance. I eliminated or reduced other histamine containing foods as well. My blood sugars were more erratic during this dietary experiment. I still was having a lot of trouble. Of course depression is the worst. Finally, After reading articles by Dr. Ray Peat, I decided to mostly or completely eliminate starch and try fruit instead as well as doing some other things he suggests in his articles. Well, one thing I have found out is that my blood sugar pretty much stays completely normal with low fasting blood sugars on a high carb but no starch diet. I am still dealing with mood issues, but slowly figuring out how to get better. From being on forums, I know many other people have had this kind of problem with low carb. I ate very little processed food on my low carb diet. I tried to eat the healthiest low carb food I could. I read lots of information about low carb diets, such as Dr. Bernstein’s book on diabetes, and “Life Without Bread.” As I said, there are many people who have had this same experience. You seem very open to more information about food and diet, so I thought I would post this here. If you have any thoughts on this, I would be interested.

    • Hi Sarah

      Thank you for sharing your experience here. Each of us is different so I would never discount your personal experience. What I would say is that the side effects of any given diet, including a ketogenic diet, are almost always due to the types of foods eaten by a particular individual as opposed to the macronutrient ratio of the diet. For example, I felt lousy on a ketogenic diet that contained processed meats but feel wonderful on a ketogenic diet that contains only fresh/frozen meats. My blood sugar, as you can see from my posts, is incredibly stable and normal on a ketogenic diet with almost no carbohydrate. But without knowing the nitty gritty details of your various diets, it’s hard to say what may have been going on. It can be tough to figure out, for sure.

  • Fiona

    Hi Dr Ede, I’ve been on a LCHF diet for two weeks now. All was going well and I was really enjoying it but now insomnia has hit big time and I don’t know what to do? Should I increase my carbs in the evening to get the tryptophan ? I’m not keen on taking any taking pills. Thanks for your advice.

  • Auggiedoggy

    This is a pro-low carb site so it comes as no big surprise that it gives a glowing testimonial to LCHF diets.

  • kerri

    Hi Dr Ede, I understand you also had chronic fatigue syndrome. Me too, recently diagnosed (housebound, low cortisol, low DHEA), pain and insomnia for more than a decade. It was a gradual burnout including over-training over the past 20+ years (the no pain no gain era, thinking that aerobic exercise and keeping busy were the cure-all to lethargy).

    I started cutting down carbs to less than 50g/day in early January 2016, however I did not feel an improvement in energy levels over 5 weeks. So from 17th Feb, I started eating only meat, butter, eggs and bacon. My fasting blood sugar levels stayed above 90 (5mmol/L). After reading Dr Rosedale’s diet, from 28th Feb, I cut my protein intake to below 75gm/d (I weigh about 55kg) and have since maintained FBG between 75-85 (below 4.5mmol/L) from 5th Mar onwards.

    I average about 150gm/day of fat including from heavy and sour cream However, my physical energy levels have still barely nudged. My fasting ketones on ketostix is about 4- 12mmol/L.

    Since 9th Mar, I eat only 250gm of lightly cooked mince beef / day (ie 50gm protein) and butter and drink water. I only use salt and pepper. Overall, my skin and brain fog has improved, so has the post-prandial somnolence when I am careful with meal quantities, pain levels slightly reduced, my insomnia improved after I religiously drank 2L a day for the past week. But my body still feels weak, its like the muscles still do not know how to utilize fatty acids, haha. Do you think I should continue to stick to mince beef (I read its supposedly easiest to digest and least intolerant) and butter and water for another month and wait it out? I am also not sure if ketogenic is the correct approach to tackling CFS / low adrenal hormones? Should I increase fat? or protein? Would taking MCT oil (no salicylates) be helpful to increase concentration of ketones to infiltrate the blood-brain barrier that might stimulate the HPA-axis?

    Appreciate if you have any comments. Thanks!

    • Hi Kerri

      Yes, I used to have chronic fatigue, and I’m really impressed with everything you have tried so far to feel better. Of course I can’t be sure what approach will ultimately work for you, but I wonder if you have a sensitivity to bovine (cow) proteins. Dairy was a major culprit for me, and for some people with dairy sensitivity, there can be a cross-reaction with beef, as both foods come from cows. Beef often is not extremely fresh, because the convention is to hang beef for at least a couple of weeks before it is cut for sale in order to tenderize it, so if you have issues with biogenic amines, this can be a second possible reason why beef can bother some people (please see my post about Histamine Intolerance). Grass-fed and aged beef are often the worst offenders. Even though butter is very low in cow proteins, it bothers me just as much as some other dairy foods, so I unfortunately need to avoid all dairy in order to feel well. I can’t think of any reason why beef would be easier to digest than any other animal food (poultry, seafood, etc).

      Another possibility is that you have not yet fully adapted to the ketogenic diet, which for some people can take 6 weeks or more. I have never tried MCT oil myself but many people swear by it as a ketogenic source of energy. I’ve heard it can cause digestive discomfort for some people, but if it doesn’t bother you, you may be able to use it as an energy supplement, at least for a while, to see if it helps your body adjust to ketosis. I know this is unusual, but I don’t count fat grams at all, just protein grams, and haven’t noticed a difference in how I feel when I eat more or less fat, as long as I get some at each meal so I don’t get hungry. Everyone is a little different, of course…

      • kerri

        Hi Dr Ede, Thank you so very much for your early appreciated response. Wow! you don’t do butter!? How do you consume enough fats? I am finding it hard to find enough good fats to consume (since I don’t do oilive and coconut oil). I just got hold of a tin of cream of tartar, since the supermarkets here only carry Lite Salt which has aluminium (anti-caking agent) and been adding it to my water with sea salt and bicarb. I also take magnesium. That helped relieve the postural hypotension. Yes, I suppose I shall have to wait 2 months into ketosis, to see if my energy levels improve. I focused on beef because it seems to be most agreeable with a lot of zero-carbers, also read about it from the “Salisbury cure”. Do you mean casein? or other bovine proteins as well? Yes, took note of histamine, thanks! Do daily calories matter? I wonder if I might be eating too little at <1500cal/day 5'4", I need digestive aids to consume enough fats and sometimes just be drinking water to calm the hunger/let the gut rest till the next meal time.

        • Hi Kerri

          I don’t worry about getting a particular number of fat grams; I just eat whatever fat comes with the meat/poultry/seafood I’m eating and I cook with plenty of animal fat (duck fat, lard, bacon fat, etc). Calories do matter under some circumstances, and you may not be eating enough calories to maintain your energy, especially if you’re not fully fat-adapted yet. In addition to casein, albumin is a bovine protein that apparently can be found in both dairy products and in beef. When I eat beef or dairy I can feel very fatigued and achey. But that’s just me, of course.

          • kerri

            Thanks for the extra tips! Hope you had a lovely Easter :). I fell off the wagaon a little but am back tweaking and trudging along… for how long and how did you discern that eating ketogenic was helpful to your chronic fatigue? Thanks!

          • Figuring out what was causing my fatigue was a long process of trial and error and there were many factors, including dairy, biogenic amines, overeating protein, and a variety of food sensitivities. Happy tweaking!

  • Leandro Oliveira

    Hi Dr. Ede

    Everyone knows that a Ketogenic Diet has been attempted in a wide variety of neurological disease and it seems to have some success.
    But, what I want to ask you is about Beta-hydroxybutyrate, the fact that it increases brain-derived neurotrophic factor production, which is also important for learning, memory and neurogenesis.
    From your own experience after shifting to ketosis, did you feel like having much more productivity or, how should I say it, better cognitive skills?

    Once again, thank you very much for your attention and for this amazing blog 🙂

    • Hello, Leandro

      YES! Eating a ketogenic diet dramatically improves my concentration, mental stamina, physical energy and overall productivity! The first thing to go when I stray from my ketogenic diet is my brain power! There is fascinating research on Alzheimer’s disease and ketogenic diets being conducted these days, as you probably know already. I gave a talk in January about this topic and the video of that presentation should be made available soon. When it is I will post it on this site and notify subscribers. Thank you for reading and for the great question!

  • Hello, Leandro

    I looked up the Wai diet and it looks very interesting. Pretty healthy, actually, as it consists primarily of fish, egg yolk, fruits, and olive oil. Unless a person has food sensitivities to eggs or fish, the protein and fat sources are excellent and sufficient. Fruits are perfectly fine unless you have insulin resistance (please see http://www.diagnosisdiet.com/how-to-diagnose-prevent-and-treat-insulin-resistance/) or fructose intolerance (http://www.diagnosisdiet.com/is-fructose-malabsorption-causing-your-ibs/).

    Constipation can be greatly helped by fruits primarily because they are easy to digest and contain sugar alcohols, which are a natural laxative (http://www.diagnosisdiet.com/food/fruits/).

    Concentration issues are complicated and may have to do with food sensitivities, too much sugar in the diet, omega fat imbalances (too much omega-6, not enough omega-3: http://www.diagnosisdiet.com/food/fats/, or artificial ingredients.

    Sounds like you’re on your way to feeling better by making healthy dietary changes!

Last Modified: Sep 2, 2015