The first thing most people think of when they hear the word “fasting” is multiple days without food. Those who have never skipped more than a meal or two think about how horrible the hunger must be and wonder why anyone would ever want to do such a thing. The few that have done multi-day fasts know that it is tough to get through the first few days.
But people that have fasted know that it is a most effective way to lose weight. They also know that there are other benefits to fasting, such as increased mental clarity, more energy and an overall feeling of being renewed. It is tough, though. Especially the first few days.
This is the kind of fasting done by Jesus during his forty days in the desert, by other prophets to strengthen their connection with the spirit realm and by the native Americans and others on various forms of “vision quests”. It is voluntary starvation in order to reach a health or spiritual goal. When taken beyond three or four days it is not necessarily good for our health. If extended beyond 12-15 days fasting can have severe negative health consequences, some not reversible.
There is another kind of fasting that is much more aligned with the way we evolved. Intermittent fasting involves shorter periods with little or no food ranging from twelve to twenty-four hours. This way of fasting seems to have a multitude of positive health effects and almost no negatives.
Before the advent of farming crops and keeping domesticated food animals, we were all nomadic hunter-gatherers without permanent homes. This also means we had no good way to store excess food(if there was any) for future meals. When and what we ate was entirely dependent on what we were able to find or hunt daily. It is doubtful that our ancestors had very many three-meal days. There were probably many one-meal days and just as many no-meal days. During those no-food days it was very important that we stayed sharp mentally and strong physically so that we could find or catch that next meal.
And we never knew what or when that next meal would be. Our bodies had to be able to use the energy and nutrition in a couple of pounds of honey from the bee hive we stumbled upon, the high saturated fat blubber of a beached whale, the almost pure protein of a jackrabbit or the starch of a bunch of sunflower root tubers. We had to be opportunists without the luxury of choosing the amount of protein, fat and carbohydrate in each of our meals, or even when we would eat those meals. This was the original intermittent fasting. This is the way we evolved and the way of eating that still works best for us. And since there were no processed foods, we ate a strictly whole food diet when we were able to eat.
The modern form of intermittent fasting has two forms. One form involves not eating solid foods for 12-24 hours either twice each week or on alternating days. The second form of intermittent fasting restricts calorie intake to 500-600 calories per day for two days in a row. Both versions allow eating a normal diet on all non-fasting days. The diet on non-fasting days should be a whole food diet for maximum health.
Health and intermittent fasting
Though the research is still fairly sparse, evidence of many diverse health benefits for intermittent fasting keep accumulating. The good effects of this kind of fasting seem to kick in very quickly, too, in as little as 6-8 weeks. Some of the documented health benefits are:
Lower average blood glucose levels and blood insulin levels
Increased insulin sensitivity
A more robust immune system
Increased amounts of brown fat(good) and decreased amounts of white fat(bad)
Slightly lower total calorie consumption compared to eating three meals every day
Increased physical energy levels
Decreased incidence of diabetes
Decreased incidence of Alzheimer’s disease and its symptoms
Increased mental sharpness
Greater capacity for muscle endurance, recovery and growth
Decreased blood levels of cholesterol and triglycerides
This is a pretty impressive bundle of health benefits for a simple change in the meal schedule. In addition, it seems intermittent fasting might also give the same benefits of severe calorie-restriction diets: increased length of healthy life and some increase of total lifespan without going through the torture of eating a near-starvation diet every day.
My personal story
Up until my early forties, I was very physically active both on the job as a professional chef and outside of work. I did a lot of hiking with heavy packs of camera equipment, biked, swam, canoed, skied, gardened, lifted weights to stay strong for all the rest of it, etc… As a chef and active person I tried to eat a healthy diet of mostly whole foods. But I also followed the conventional advice of the time by fueling myself mostly with “clean burning” carbohydrates like pasta, white rice, russet potatoes and bread and trying to keep my diet as fat-free as possible. I still maintained the same weight and waist size as when I graduated high school. I did not have to think about it, it just seemed like my natural set-point no matter what I ate or did.
This worked well except for those times when I got hungry and did not have food available. Then I would get so hungry I would become nauseous and literally not be able to think about anything besides getting something, anything, into my stomach. If more than an hour passed with no food I would sometimes get the dry heaves and shiver. I learned to always carry a ziplock of nuts or trail mix or a granola bar with me and have food in the car and in my pack at all times.
A move to a much hotter and more humid climate and a job that was much less physically demanding put major dents in the amount of calories I burned each day. But my diet did not change much. By the time I reached fifty I had gained nearly 30 pounds and four inches around my waist. I felt heavy, soft and not as strong.
After a lot of research, I adjusted my diet to eliminate almost all of the simple carbohydrates: the added sugars and simple starches. I went to an entirely whole food diet. I made an effort to walk and swim more and do a basic body-weight exercise program. After five years of never counting calories and getting on a scale only once or twice a year I am within five pounds of my original set weight and nearly back to my original waist size. And I am as strong or stronger than ever.
But what I think made the biggest difference was when I finally gave up breakfast. I had never been a big fan of breakfast, really enjoying it once in a while but mostly not caring. After eliminating simple carbs it was an effort to eat early in the morning – I just wasn’t hungry. But all of the conventional advice stressed how important breakfast was so I tried to eat something every day. I finally just gave up and stopped making the effort.
After that I realized that I didn’t much feel like lunch sometimes, either. I fell into a pattern of mostly not eating in the morning and also skipping lunch a few times each week. I started feeling even better and being hungry less often. When I was hungry it was no longer a raging “gotta get something right now” storm that made me want to eat my own foot.
Then I started seeing news stories about intermittent fasting and realized what I was doing. Following the latest research on diet and fasting, I did not feel bad about skipping breakfast most days. It seemed like a natural way for me to eat, at least now that I was older and less active. I certainly feel like I am reaping the benefits of not eating three squares every day and whole food health all of the time.
I get sick with a cold or the flu maybe every other year even though I work with the public and large numbers of co-workers. I have absolutely reliable digestion on a regular schedule all year round. I feel, and people tell me I look, many years younger than I am. And I don’t feel I have lost any of my creative edge in the kitchen, with my photography or with my writing.
So I am a firm believer in eating a healthy whole food diet and in intermittent fasting. They both come out of our heritage and evolution and fit the way our bodies and minds actually work. Man will no doubt keep trying to improve on nature by manufacturing new and improved “foods” and “medicines”, but so far does not have a very good track record. I will stick to the old fashioned foods of our ancestors and the old fashioned eating schedule until there is real proof that something else works better. For more in-depth information about intermittent fasting please click on the links below.