Even in 2013, when I originally wrote this post, most dieters already knew, “IF” was not a conjunction introducing a conditional clause.” “IF” means Intermittent Fasting. IF had already become a popular method of dieting with those who can tolerate it. They are generally people who are keto-adapted, which permits them to do it easily and without hunger. It also “feels right” to introspective types as a throwback to ancestral times when food was scarce, and hunters and gatherers ate less in the winter and more “in season” and when the hunting was good.
“Intermittent” means “coming and going at intervals,” “not continuous,” or “occasional.” It is open to interpretation “Fasting” is also open to interpretation but generally means a period in which no calories are consumed during the fasting period. In common usage when applied to the human diet, that definition always includes water and is generally includes beverages such as black coffee and plain tea. Personally, I stretch it further to include heavy cream with my morning coffee and liquid stevia with iced tea during the day. That being said, just skipping dinner once or twice a week can have miraculous effects without much effort.
According to the Wikipedia entry, “There is evidence suggesting that intermittent fasting [IF] may have beneficial effects on the health and longevity of animals – including humans – that are similar to the effects of caloric restriction [CR]. The myriad health and longevity benefits have mostly been seen in animals (e.g., rats and worms). They include: reduced serum glucose and insulin levels, increased resistance of neurons to stress in the brain, reduced blood pressure, increased insulin sensitivity, and increased heart rate variability; also: increased resistance of heart and brain cells to ischemic injury and age-related deficits in cognitive function.”
Again, according to Wikipedia, “the benefits of Intermittent Fasting are a direct consequence of the period of fasting, not from the decrease in overall calories consumed. Fasting has its own specific benefits related to the body’s multiple biochemical adaptations to maintain homeostasis. The body engages in Hormesis, a process of renewal and repair.” These mechanisms are not fully understood, but they are wondrous! It never ceases to amaze how “happy” my body is, physiologically speaking, whether I am in either the “fed” or the “fasting” state.
As a weight loss tool, two specific forms of IF are commonly practiced: the alternate day fast in which no food whatsoever (excepting water, black coffee or plain tea, or my version) is ingested for one whole day. This is actually a 36-hour fast, from dinner one day (7:00pm) to breakfast the day after (7:00am). The other form is more moderate and more popular. It is commonly referred to as the 8/16 hour fast in which all food in a 24-hour period is consumed within an 8-hour window. For an office worker, this could be done by skipping breakfast (except for coffee), eating a light meal in mid-morning break (10:00AM), a light lunch at 12:30 (if hungry) and dinner at home at 6:00PM, all within the 8-hour window, and then you begin the 16-hour fast.
I have a favorite 3rd version of IF, as I sometimes practice it; I call it “The 23-hour IF Diet.” I start with coffee with heavy cream when I rise. There is nourishment here, but virtually no carbs. I stay in ketosis. (I just never developed a taste for black coffee or plain tea), so this beverage is the beginning of a 1-hour eating window. Then, when my spouse arises and prepares breakfast, I eat 2 fried eggs and 2 strips of bacon. For variety on weekends we might “hold the bacon and substitute 3 eggs scrambled, with a little cream and/or shredded cheese, or smoked salmon tidbits mixed in. No lunch, no supper, no snacks. Just water or iced tea during the day when the body asks for it.
I created “The 23-hour IF Diet” spontaneously a while back to deal with weight creep. I did it for two days in a row – just breakfast, nothing else for two days. First, I was not hungry because my body was “fat adapted,” but I had built up glycogen stores in the liver from some previous “cheats.” I was primed to return to a fat-burning state as my body used up the glycogen stores for energy and eliminated the water retained by it. So, it worked. The first day I lost 5 pounds – largely water, of course, and on the 2nd day, 2 more. 7 pounds total. As I say, it worked.