Keto for Cancer: Week 1—My Transition to Ketosis

A bumpy transition to ketosis

Ketosis for cancer week one

Fasting for more than 36 hours proved challenging in ways that took me completely by surprise so I decided to break my fast on Day 4 and continue my transition to ketosis while eating food. My goal remains to reach Prof. Seyfried's recommended "zone of metabolic management": blood glucose between 55 and 65 mg/dL and blood ketone levels of at least 4.0 mM. How much protein should I eat to try to get there? How many calories?

Note: this post was originally published on Aug 1, 2013. It was edited to streamline content and improve graphics in June 2016; therefore some older comments may pertain to content that was removed during revision.

This post is part of a series describing my attempt to follow Dr. Seyfried's dietary recommendations for cancer. To see what happened on Days 1-3, please go to the first post: "Seyfried’s Ketogenic Cancer Diet: My Fasting Jump-Start to Ketosis."

A funny thing happened on the way to ketosis . . .

Day 4 (2/3/13)—fourth day of fasting

Day 4 nutrition journal entry - fasting

Notes: Only slept from 2 am to 5:30 am. Big jump in ketones this morning, but hungrier. Numerous unhappy symptoms: difficulty concentrating, tired but couldn't sleep, mild headache, low energy, a little cold, heartbeat a little stronger than usual, dark circles under eyes, stomach growly, and slight tinnitus (ringing in the ears). At this point, I considered breaking the fast, but then something happened that convinced me it was time to eat.

My cell phone rang at about 2 pm [my ringtone is a harp playing a lovely arpeggio; you may be familiar with it]. Anyway, I answered the call, spoke for a few minutes, and then hung up. But the harp kept playing, very faintly and mysteriously, in the distance, nowhere near where my phone was located . . . over and over again. Uh-oh. I realized that I must be having a mild auditory hallucination—certainly something I had never experienced before in my whole life. While absolutely fascinating to me on one level, it was a clear indication that my brain was not getting the nutrients it needed to function properly, so quite concerning on another level.

This hauntingly beautiful harp call was either a sign that my ascension was drawing nigh, or it was time to have some lunch. I chose lunch:)

What does this mean for cancer patients?

What does this mean for people with cancer who may have been considering fasting up to 5 days to rapidly establish ketone levels of 4.0 mM? It may mean nothing. It may be my own unique response to fasting. Perhaps some people tolerate fasting for more than 3 days beautifully. However, at least for me, fasting for longer than 3 days was not tolerable, and to have continued the fast would have been unwise.

Now, if I had continued another day or two until my ketones had risen to 4.0 mM, would all of the side effects have gone away? I don't know. If I had already been keto-adapted (at lower ketone levels), would I have tolerated the fast better? Maybe, I don't know. But since the point of the fast is to change from a regular diet to ketosisk as rapidly as possible, people who try this plan aren't expected to be keto-adapted already. In most cases, I think it may be wiser to try Dr. Seyfried's alternative initiation plan instead of fasting (see details in the "Dietary Treatment of Cancer" post).

I certainly could never have accomplished his recommendation of an annual 7-day fast, so my cells will not have the opportunity to cannibalize each other after all. I am just going to have to hope that my healthy diet naturally reduces my risk for developing pre-cancerous cells in the first place.

The transition to a ketogenic diet

What's next? I will continue to try to reach Seyfried's "zone of metabolic management" while eating a carefully measured, mostly meat, ketogenic diet.

First, I need to calculate my protein requirements. Based on my personal stats:

  • Dr. Seyfried recommends I eat between 62 and 92 grams of protein per day.
  • Phinney and Volek recommend I eat between 75 and 156 grams of protein per day.
  • Dr. Rosedale recommends I eat 77 grams of protein per day based on my body measurements, but 47 grams of protein per day based on my body fat percentage.

Hmmmm . . . since protein requirements are clearly difficult to estimate (see my protein page for more details), and one size does not fit all, I'm just going to start with 75 grams of protein per day, and if I need to adjust it along the way, I will.

If I were trying to treat cancer, Dr. Seyfried would want me to reduce my calorie intake significantly below my daily requirements (resting/basal metabolic rate or "BMR"). My estimated BMR is 1400 cals/day, so I'll try to keep my calories to a maximum of 1400 per day.

Day 4, continued:

Day 4 nutrition journal entry

Notes: I felt much better about an hour after eating some food. It was especially wonderful to regain my powers of concentration. And surprisingly, despite having not eaten a thing for nearly 4 days, once I started eating, my appetite was actually fairly low. Therefore my calories for the day were also pretty low. Was this the effect of high ketone levels/low insulin levels?

Day 5 (2/4/13)

Day 5 nutrition journal entry

Notes: Got very hungry at dinnertime but a very small amount of food was required to feel better (8 g protein + 13 g fat).

Day 6 (2/5/13)

Day 6 nutrition journal entry - transition

Day 7 (2/6/13)

Day 7 nutrition journal entry - transition

Reflections on my transition to ketosis, week 1

  • Fasting certainly does jump-start ketosis, but fasting for more than 36 hours may not be safe for everyone, and was no fun.
  • Appetite is generally much lower as ketones rise.
  • Hunger feels different in ketosis than on a standard diet. I experienced mild headache, stomach growls, calm thoughts of food, can still go hours without eating and function fine. Zero emotional component. Compare this to hunger on a standard diet, which (for me) = irritability, anxiety, distractibility, emotional longing for food, sense of urgency, carbohydrate cravings, and wish to stop whatever I'm doing and find something to eat right away.
  • My blood sugar is still pretty high despite high ketones, but I think all bets are off during first few weeks, as "keto-adaptation" can take 3 weeks or more. [Keto-adaptation refers to the body's adjustment to the efficient use of ketones for fuel instead of glucose.]
  • Do I need to eat more fat to get higher ketones, or is it just a matter of time? If I were to eat more fat, that would mean more calories—would weight loss slow down or stop?
  • I am hesitant to do any experiments within my experiment until after a month of this plan, so for now I'm going to stick with: 75 g protein, 1400 cals max, carbs less than 30 g/day, mostly meat, no dairy, no caffeine, no artificial anything.

Check out "Keto for Cancer: Week 2—Protein and Ketosis" to see how I got my ketones way, way up. For information about starting a ketogenic diet yourself, see my online guide: "Ketogenic Diets 101."

Recommended ketogenic diet and cancer resources

  • Cancer as a Metabolic Disease
  • Tripping over the Truth book cover
  • Keto for Cancer book cover

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