As a nutritionist, I get questions all the time about the potential benefits of fasting.
People fast for many reasons — for quick weight loss, to “detox” the body, for religous purposes, or even as a political protest. Here is the latest info on the myths and facts of fasting. Before you forsake your fork, read this:
Fasting and weight loss
Most experts (this one included) do NOT recommend fasting as a way to lose weight. If you’re itching to shed pounds, a drastic cut in calories may see like the fastest way to see instant results. However, when you eat less food, your metabolism slows down to conserve energy. Then, when you go back to your usual diet, your lowered metabolism may cause you to store more energy, so you will likely gain back the weight you lost and possibly even put on more weight when eating the same calories you did before the fast.
Fasting to “detoxify” the body
Many fad diets include a “detox” phase during which dieters are instructed to drink only water or herbal teas. But there is scant scientific evidence showing that fasting will detox or cleanse your body. Fasting does not boost the body’s disposal system, or cleanse your body in a healthy way. Some people say they feel great during or after a fast. They might feel great because they believe fasting is healthy or has a significant spiritual meaning, or they might feel great because severe calorie restriction (like fasting) can produce feelings of happiness or even euphoria. In either case, fasting isn’t actually doing a body good. What’s the long-term solution for cleansing your body, then? Eating a sensible diet with plenty of fruits, vegetables, whole grains, lean protein, and unsaturated fats.
However there are some interesting studies indicating that, under some circumstances (and always under medical supervision) fasting may boost health.
NOTE: If you are considering any type of fast, it is imperative that you check with your doctor first. Fasting can be harmful for some people, including pregnant and breastfeeding women, the elderly, and individuals with certain health conditions.
Fasting and heart health
News emerged this week that regular fasting may be good for your heart. A study found that periodic fasting not only decreases the risk of heart problems and diabetes, but may also lower blood sugar levels. The researchers found that people who fasted regularly had a 58 percent lower risk of coronary disease compared with those who said they didn’t fast. The study was conducted by researchers at the Intermountain Medical Center Heart Institute (IMCHI) in Utah. Study findings were presented at the ongoing annual scientific sessions of the American College of Cardiology in New Orleans. While these findings are intriguing, experts say it is still too early to conclude that fasting should be used as part of a heart health prevention plan.
Fasting for a longer life
Meanwhile, caloric restriction, while not a strict fast, has been shown in numerous studies to extend life in rodents, yeast and various insects. The National Institute on Aging funds several projects investigating this possibility in monkeys. Investigators at Washington University in St. Louis are studying members of the nonprofit Calorie Restriction Society, a group that exists to promote this type of research in humans. Several compounds also are under investigation in hopes of reproducing the benefits without the negative aspects and challenges of ingesting so little food.
The Bottom Line: For most healthy people, a day of fasting for spiritual or religous purposes will not cause harm. However, while there is some interesting research on the benefits of fasting/calorie restriction, more studies are needed to determine just how fasting can effect the body. So hold on to your fork and keep eating healthy meals and snacks. It’s good for your body… and tastes good too!