As science continues to investigate the role fasting plays in healing our bodies and balancing our body weight, it seems increasingly likely that limiting our calorie intake over time has the potential to lower blood pressure and protect us against the aging process. But, with so many “authorities” online touting different eating windows and fasting methods, how long should we really aim to fast and when is the best time of day to eat? Also, is it safe to fast as you get older? We spoke to Steve Hendricks, author of “The Oldest Cure in the World: Adventures in the Art and Science of Fasting” for his thoughts.
Steve Hendricks has studied fasting from both an academic and personal perspective, even settling into various fasting clinics to gain a global perspective. “I’m 52 and started getting interested in fasting in my 30s,” he says. “Like many people, I started gaining weight when I was 20 and was interested in ways to bring it down. Fasting is not a magic bullet for weight loss, but it can be a useful tool.Before discovering fasting, I had experimented with simple calorie restriction, which simply means eating less each day, but CR is notoriously difficult to achieve due to the constant gnawing hunger.
“Fasting, I was thrilled to discover, as so many people have done, is much more doable than CR because fasting actually suppresses hunger. Even better, fasting triggers many of the same mechanisms of healing than CR.Our body is repairing cellular damage all the time, damage that can eventually become disease, but usually these repairs only happen at a very slow rate because the body is so busy with other things like processing nutrients from our meals.But when we give the body a break from processing nutrients, it uses the downtime to speed up repairs, helping to prevent disease and giving us an extra opportunity to live longer. It’s a wonderful mechanism, perfected by at least a billion years of evolution, and we now have good science to guide us in how to use it.
How long should you fast?
Studies have shown that even extended fasts of four to 21 days are beneficial, providing benefits in cardiovascular protection, fat loss, and emotional well-being. “Most fasting physicians recommend that adults do some sort of maintenance fasting for a week or more, once a year, under competent medical supervision,” says Hendricks, who believes daily intermittent fasting should always include timed calorie restriction for at least 12 hours. in order to receive benefits. “It’s no coincidence that 12 o’clock is about the point where people tend to start reporting that they feel better and have more energy than they have. had when they ate all day,” he says. “With every hour you shave that 12-hour window, the health gains could increase dramatically. Scientists aren’t sure what the ideal eating window is, but most seem to think it’s around 6 a.m. Reducing the window below 6 hours may not be helpful, however. If you’re eating in, say, a 4-hour window, some scientists worry that the disadvantages of cramming an entire day’s worth of food into your gut in such a short time may outweigh the benefits of a longer fasting period. .
Is there an optimal time to eat?
“It’s much healthier to arrange your eating window earlier in the day,” says Hendricks. “Our circadian rhythms have hardwired us to digest food and process nutrients most efficiently in the morning and early afternoon. Obviously, the longer the day gets, the more our bodies hurt at such tasks and it seems like there’s nothing we can do to change that, so when we eat in the late afternoon, let alone in the evening or at night, food and nutrients linger in our intestines longer and our blood vessels, where they can cause damage.Eating later interrupts many of the cleaning and repair processes our bodies go through at night while we sleep, which can increase our risk of disease.
“The science on exactly when to start your feeding window is not yet settled, but I think most scientists in the field would say it’s likely to fall about an hour or two after you wake up. For a lot of people that would mean eating in an 8am to 2pm window each day I know it sounds crazy to have dinner at 1:30pm rather than 6pm I sure wasn’t looking forward to it when I tried it for the first time, but people who have made the switch, including me, report that it turns out to be a remarkably easy change to make after the first few days. If you can’t eat on this type of schedule for a For some reason, a compromise might be to go ahead and eat dinner at your usual time, but keep it light and rack up most of your calories at breakfast and lunch.
Is it safe to practice fasting at any age?
Hendricks thinks fasting can be adopted as early as adolescence, initially eating within a 12-hour window, but there’s no reason to give up the habit as you get older. “Many fasting scientists and physicians have concluded that a daily fast of approximately 18 hours a day is safe and healthy for adults of all ages,” says Hendricks. “There are so many health benefits to eating within a narrow eating window; our levels of inflammation throughout the body will drop, insulin sensitivity increases, more antioxidants are produced, and more worn-out cell parts are recycled. The ideal age to start is early in life to establish daily fasting as just the normal way you organize your diet.
Tips for getting started with intermittent fasting
“If fasting seems difficult, take it easy at first,” says Hendricks. “If you’re eating for 15 hours a day now, you might find it difficult to go to 6 hours right away. Doctors and researchers who practice fasting recommend simply removing an hour from your eating window for about a week, and once you’re comfortable with that, remove another hour, and then possibly another hour. If you can get it down to 6 or 7, great. If that’s too difficult for some reason, congratulate yourself on eating within the narrow window you can reach. Any window of 12 hours or less will give you health gains.
“Also, don’t let perfectionism get in the way. If you want to go out with friends for a late dinner once in a while, that won’t derail you too much, although you’ll probably notice that you’re feeling a bit slower the next morning. Likewise, if you’ve done a heavy workout in the middle of the day and later realize that you haven’t eaten enough during your eating window, go ahead and eat a little more so you don’t get hungry for more. throughout the evening and that your muscles have the basic elements to recover.
The World’s Oldest Medicine: Adventures in the Art and Science of Fasting by Steve Hendricks is now available.