The advice to have five or six small meals daily has become common in recent years. I am 69 years old and don't recall ever hearing this as a child and seldom as a young adult, but by the 1980s it seemed to be everywhere. Today, it is close to nutritional dogma. It is not surprising that an online search of the phrase "eat many small meals" returns over 275,000 results.
The usual justification for eating extra meals is that it keeps the metabolism "revved up" so that weight loss is easier. There is, however, very little hard evidence that supports this idea, and a fair amount that disputes it. For example, a research analysis published in the British Journal of Nutrition concluded that "any effects of meal pattern on the regulation of body weight" appear to be negligible, and what matters is total food intake.
Worse, the "eat many small meals" advice has two clearly negative effects:
So the time has come to explore the opposite idea: regularly allowing greater-than-normal amounts of time to pass between meals, a practice known as "intermittent fasting," or IF. Frankly, today in America, simply eating three meals with no snacks might be called a form of IF, if only by way of contrast. If we were to return to this once-common practice, I believe we would be healthier for it.
The basic premise of IF is to enjoy better health via repeatedly fasting for longer periods than is typical on a daily breakfast-lunch-dinner schedule. Variations are endless. Some proponents skip breakfast; others, dinner. Others fast all day every other day, every third day, once per week, or once per month. A friend I know who travels for work six to eight times annually always fasts on the first and last days of his trips, reasoning that airline food is awful anyway. (Fasting, it should be pointed out, means abstaining from solid food; all sensible IF plans allow hydration with water, tea or other no- or low-calorie beverages.)
An IF regime works, proponents say, because it aligns with our evolutionary history. Over the 250,000 years that Homo sapiens have been around, food supply has waxed and waned. We evolved to take advantage of this fact, building muscle and fatty tissue during times of abundance, then paring it back during lean ones. Fasting periods accelerate the clearing-out of waste left by dead and damaged cells, a process known as autophagy. A failure of autophagy to keep up with accumulated cellular debris is believed by many scientists to be one of the major causes of the chronic diseases associated with aging.
Occasional fasting also seems to boost activity and growth of certain types of cells, especially neurons. This may seem odd, but consider it from an evolutionary perspective -- when food is scarce, natural selection would favor those whose memories ("Where have we found food before?") and cognition ("How can we get it again?") became sharper.
Research indicates that the benefits of IF may be similar to those of caloric restriction (CR) in which there are regular meals, but portions are smaller than normal. The advantage of IF, proponents say, is that it's easier to feel sharp hunger occasionally rather than the mild hunger of CR virtually all the time.
The positive effects of IF have been chronicled in a variety of animal and human studies, starting with a seminal experiment in 1946, when University of Chicago researchers discovered that denying food every third day boosted rats' lifespans by 20 percent in males, 15 percent in females. A 2007 review by University of California, Berkeley, researchers concluded that alternate-day fasting may:
What should we make of this?
I don't recommend IF for everyone. Children under 18 should not fast, nor should diabetics, nor pregnant or lactating women. Some health conditions -- such as severe gastrointestinal reflux disease, or GERD -- are easier to manage when food intake is more regular.
But I do think the evidence for the health benefits of IF should make us rethink what seems to be a modern cultural imperative: to avoid hunger at all costs. To the contrary, getting hungry now and then is clearly a healthy thing to do as long as overall caloric intake stays high enough to maintain a healthy weight. (Fasting, like every other healthy activity, must be done sensibly and in moderation.) Many people who follow IF regimes report both physical and mental benefits, including improved energy and concentration, better sleep, and an overall feeling of well-being.
If you practice IF, please share your experiences in the comments below -- what's your eating-fasting pattern, and what health effects have you noticed?
Andrew Weil, M.D., is the founder and director of the Arizona Center for Integrative Medicine and the editorial director of www.DrWeil.com. Become a fan on Facebook, follow Dr. Weil on Twitter, and check out his Daily Health Tips Blog.
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Since I can't stomach green/veggie juices, I've modified my once a week fast by having some grapefruit/tangerine juice in the morning then an apple or avocado in the afternoon and a small kale salad (about 1 cup) for dinner and perhaps a bit more juice. I still drink coffee because I do each Monday and need to work.
I find that the once a week fast is relatively easy to do and helps keep me more focused on the calories I consume in the successive days. My skin looks great (although typically does anyway as I eat very healthy). My day of workout rest I coincide with the fast.
It seems to work for me but does require some discipline.
When I lived in a Latin American country, we ate that many times a day, and I lost weight. The difference? I didn't have a car to drive in all day and eat out of while stuck in traffic. So in the U.S. just cut back on the calories.
Eating regularly helped me keep from gorging myself. It helped me to think that I had a regularly planned eating time coming up in 2 to 3 hours and that I didn't need to think about making it to the next meal without a snack. Interestingly, I now really can't gorge myself. My stomach has shrunk so much that I can't eat as much as I used to in one sitting. It may not work for everyone, but it worked for me.
I, too, don't believe "one size fits all" as an approach to eating.
People should be encouraged to learn what works for them.
I'm sure it would be easy for someone to write an article the opposite of Weils----why IF is bad for you and eating 5-6 meals a day is best.
I have been IF'ing at least once a week for about 2 years now. Usually early Saturday evenings around 5pm to Sunday afternoon around around 2-3pm. Virtually everyday also, I will not have my first main meal till around around 10:30-11:00am.
Given that I rise from bed around 5am and have a very active lifestyle as nutritional consultant and H.I.I.T trainer, i experience no hunger or lack of energy issues what-so-ever.
My 2 main meals of the day are based on whole foods with a considerable amount of good fats, ethically and environmentally sourced protein and vegetable carbohydrates. Fats are absolutely critical on so many levels - and apart from the nutritional and hormonal benefits, fats SATIATE!
I do snack but mostly of nuts, seeds, goji + inca berrries and avocados. I make my own chocolate from Coconut Oil, Cocoa Powder, stevia and add either chili or almonds, or goji's as i do love chocolate.
Once you manage to IF successfully you will start to garner control over your eating habits, and take control of 2 hormones that play a key role in our consumption of food - Leptin and Ghrelin.
That in itself can be a struggle as they can be quite dictatorial.
I am 45 and enjoy not only splendid physical health, but very positive mental wellness. I am over enthusiastic about the need to proper food, nutrition, digestion, sleep & rest.
This works for me.
The majority of the times i do not consume anything before my Tabata training apart from black coffee, however on occasions i may eat a little protein and plant carbohydrate.
Coffee is a great exercise motivator and some recent research articles indicate caffeine has some very positive effects on exercise performance :)
I will however, eat within 30-40 after training
Cravings - good fats seem to help with cravings for sugar and sweet foods. I also recommend to clients 5-HTP or Rhodiola to assist with will-power, cravings amongst other benefits.
Homemade choc 'is' delish!!
Basically Binging and then starving yourself
This is an eating disorder not a diet
Many women figured out that you can do what he is advocating and still eat every day. Its called purging
Most doctors woudn't recommend things like that
This one does for some reason. I'll stick with the majority on that one
At home, I eat a big salad with a lot of veggies and lean protein. Then I'll have Greek yogurt and whole grains like quinoa, millet, or rolled oats. To help my body digest and process the food, I take a digestive enzyme pill each night.
I've done this for a few years and enjoy it just fine. I can go almost all day on weekends without food and still function fine. It might be a slow change, but you feel less burdened by trying to eat every few hours.