Retrospective #383: Fasting on 300kcal a day while fat-adapted

This post was originally published 3 years ago (2017), when I first tried full-day fasting to break a weight loss stall.

I have been eating Very Low Carb (VLC) for about 15 years. I lost 170 pounds, but inevitably gained some of it back. Losing it the 2^nd time proved to be harder, so I decided to try Intermittent Full-Day Fasting (IF).

I gave up my breakfast of eggs (I wasn’t hungry anyway) but kept a cup of coffee with heavy cream and stevia powder to take with my pills. I sometimes ate a light lunch (all protein and saturated fats) and then a supper of animal protein and one low-carb vegetable, with more fat (olive oil or butter). I did it for about a year, and it was easy. But, I didn’t lose weight! It was satisfying, but still too much food. I needed to try something else.

Then last fall Megan Ramos, director of Jason Fung’s Toronto IDM Program, suggested full-day fasts, i.e. the “other” kind of fasting. I told Megan that during a 2-month period during the winter I would do it, and I did. In 10 weeks, I lost 31 pounds. With that success under my belt – why mess with success, right? – I decided to do it again, this time breaking new ground with the goal of reaching a weight I haven’t seen since my early teens.

How did I do it? What is the secret of my success? Full-day “fasting,” my way. I put “fasting” in quotes because, on days when I fast, “my way” is not a strict, water-only fast, although it is a basically a liquid fast. For Breakfast I drink a 12-oz coffee with 1½ oz of heavy cream and a smidgen (1g) of powdered stevia. If I feel dehydrated during the day, I will have just iced tea, sweetened with liquid stevia, and a pickle slice or just a pickle juice. Then, for Supper I drink 6-oz of red wine in a large glass filled with seltzer (with my evening pills ;-).

Macronutrients: Coffee w/cream: Fat: 16g (144kcal), Protein: 1.2g (5kcal), Carbs: 1.2g (5kcal); Total: 154kcal. Spritzer (6oz): Carbs: 4.5g (18kcal), Ethyl alcohol: 18g (126kcal); Total: 144kcal. Fasting day total: 298kcal. Say 300kcal/day.

This is a departure from the usual “water-only” fast in three respects: 1) it includes dairy, 2) it includes a sweetener (pure stevia, sweet but not artificial), and 3) it includes alcohol. Total carbohydrates: about 6 grams/day.

THE SECRET FOR THE SUCCESS OF THIS “FASTING” REGIMEN IS THAT ON “FEASTING” DAYS, I EAT VERY LOW CARB. THEREFORE, I AM NOT HUNGRY BECAUSE I AM ALREADY “FAT-ADAPTED.” FAT-ADAPTED MEANS THAT MY BODY IS ALMOST CONTINUOUSLY IN “NUTRITIONAL KETOSIS.” ON “FEASTING” DAYS MY BODY MAINTAINS ITSELF ON WHAT I EAT, WHICH IS HIGH-FAT, MODERATE PROTEIN AND VERY LOW CARB. FOR ENERGY IT USES THE CARBS I ATE AND ANY STORED IN THE LIVER AS GLYCOGEN, THEN THE UNUSED GLUCOGENIC PROTEINS STORED IN THE LIVER AS AMINO AND THE DIETARY FAT. THEN, IF MY BODY NEEDS MORE ENERGY FOR WHATEVER ACTIVITY OR JUST TO MAINTAIN HOMEOSTASIS, IT SIMPLY TRANSITIONS TO BREAKING DOWN BODY FAT. MY BODY FAT IS ACCESSIBLE BECAUSE OF MY LOW BLOOD INSULIN LEVEL BECAUSE OF MY VERY LOW CARB INTAKE. THAT’S FAT-ADAPTED!

At first, even though I’d read Jason Fung’s book, “The Obesity Code,” I had trepidations about not eating from one day’s supper to “breakfast” (my cup of coffee) two days later. So, I started off with the idea of alternate day fasting (Tuesday and Thursday) every week. But I was surprised how easy it was (being fat-adapted to begin with), since I was not hungry at any time, day or night, including at “breakfast” on the day after. So, I decided to try 2-consecutive-day and then 3-consecutive-day fasting. Again, it was easy. No hunger. Lots of energy. I was alert, pumped, actually.

I take Metformin twice a day: 750mg ER (extended release). I did not reduce my meds, but then after a full day of fasting my FBG dropped into the mid 60s (3.6-3.7mmol/L). Once my FBG dropped to 60mg/dl (3.3mmol/L), and I still felt fine. On a 3-consecutive-day fast, my FBG would be in the mid 60s all three days. I mentioned this to my doctor, and with a brush of his hand, he said, “Don’t worry about it. You can never get hypoglycemic on Metformin.” And I never did. The liver makes glucose, via gluconeogenesis, from both dietary protein (amino acids) and body fat (the glycerol molecule when a triglyceride breaks down).

And when the lab report came back, my A1c had dropped a full half percentage point from 5.8% to 5.3%.