“What a noble soul must one have, to descend of one's own free will to a diet which even those who have been sentenced to death have not to fear! This is indeed forestalling the spearthrusts of Fortune.”
—Seneca, Moral Letters to Lucilius. Letter 18
Fasting is an awesome way to ramp up your insulin sensitivity, crush inflammation of any kind, train your fat metabolism, destroy precancerous growths, and combat the common diseases of civilization. It’s the ultimate physiological reset.
If you’re already on ketogenic or otherwise low-carb-high-fat (LCHF) diet, fasting for a few days to a week shouldn’t be much of a struggle. We’ve picked up a few tricks along that way, however, that can not just ease the discomfort, but make the experience downright pleasurable.
The goal at the start of your fast is to enter deep ketosis ASAP, so these recommendations on fasting are applicable to the maintenance of nutritional ketosis, as well.
- Supplement with magnesium and potassium. Without these electrolytes, you may begin to suffer from insomnia and obnoxious muscle twitches around day two or three. I do 400 milligrams (a standard supplement pill) twice a day of magnesium and one gram of potassium citrate (about 1/8 teaspoon) two or three times a day. Add sodium and calcium if the above trio doesn’t fully do the trick. Anyone on a ketogenic diet should be supplementing with similar doses already.
- Don’t stop exercising, but keep it light and aerobic—you should be able to easily hold a conversation and shouldn’t have to open your mouth to breath. A lengthy walk or an easy run is a great way to boost ketosis. Aerobic exercise and direct sunlight also significantly decrease cortisol, the stress hormone that causes muscle wasting and can stymie fat-burning and ketone production. These are especially important in the first few days of your fast to shorten the period of high-cortisol before full-blown ketosis.
- Supplement with branch chain amino acids (BCAAs) in the morning and during any exercise. This can virtually halt any muscle wasting during the fasting period. Dose is 1.5 grams, about a teaspoon. Double that for lengthy exercise. This is also most important in the first few days.
- When a wave of hunger hits, have a spoonful of coconut or MCT oil and a swig of apple cider vinegar. The effect is a magical and near instant cessation of hunger. Small amounts of pure fat are legit during a fast, especially if you’re already at goal weight.
- Reward yourself with small treats towards the latter half of the fast. I’ll have a bowl or two a day of hot broth with shredded seaweed and a heaping spoonful of ghee mixed in. It's full of electrolytes and feels downright decadent after not eating anything for days.
- Splurge on good mineral water. Fasting will make you thirsty. Since this is all you’re consuming during the fast, don’t be afraid to go for for the good stuff. I prefer sparkling spring water with a high-mineral content.
- Transition to keto for a week or two prior to beginning the fast, and/or experiment with intermittent fasting (consolidating each days’ meals into a six-hour window). This isn’t strictly necessary, but it will ease your suffering considerably.
- Fast often. I fast a few times a year, once for a week and the remainder for three or four days a pop. They’ve become so painless I now schedule them during normal work weeks, though when starting out I’d only do them during holidays or long weekends.
Seneca’s 2000-year musings on intentional deprivation are a great guide not just to fasting and ketosis, but to training, adaptation and mindset, in general. We’ll finish up with the remainder of the quote that started this entry:
“It is precisely in times of immunity from care that the soul should toughen itself beforehand for occasions of greater stress, and it is while Fortune is kind that it should fortify itself against her violence. In days of peace the soldier performs maneuvers, throws up earthworks with no enemy in sight, and wearies himself by gratuitous toil, in order that he may be equal to unavoidable toil. If you would not have a man flinch when the crisis comes, train him before it comes.”
Be sure to let us know your own tips and experiences in the comments below. Happy fasting!