The Cheater's Guide to Fasting

by Valerie Berkowitz, M.S., R.D.

The cheater's guide to fasting
The cheater's guide to fasting

With all the news on fasting lately, you may have considered trying a fast but worry that you cannot avoid food for 24 (or more) hours without food. According to a new study, though, you can cheat and still reap all the benefits of fasting.

Researchers at the University of Illinois at Chicago put a group of obese volunteers on either a 25-percent-fat diet or a 45-percent-fat diet. All participants alternated between days of eating 125 percent of their calorie needs and fasting, although they were allowed to eat up to 25 percent of their metabolic needs during a 2-hour window on fast days.

After eight weeks, both groups lost significant amounts of weight without losing muscle mass and reduced
visceral fat, the deadly fat that surrounds your internal organs. The higher-fat diet also had better compliance and lost more weight. No surprise since fat adds palatability to meals. I have seen my clients consume meat, avocados, olive oil, and other high-fat foods that add more calories to meals yet still result in an average of five pounds of weight loss a week, along with improved cardiovascular risk and body fat composition even without fasting.

So if you are interested in losing weight, you may not need to change the type of diet (low fat or higher fat) that you already follow-just change your eating pattern. And if you decide to try alternate-day fasting (ADF), you may be able to do so without complete deprivation on fast days and still lose weight.

RELATED: Not all weight-loss plans work for everyone, including fasting. Find the best time to eat to lose weight for you.

What I thought was interesting, as it may shed light on a metabolic phenomenon that we do not fully understand, is that despite the 50-percent calorie deficit over a two-day period, volunteers maintained lean body mass instead of losing muscle.

Fasting or ADF isn't for everyone. You may want to read Stefani Ruper 's blog. She reviewed the literature and found specific gender differences that may cause reason for concern for some women who fast.

My clients ask me all the time, "What diet should I follow?" and my reply is always the same: The diet you choose should be one that you will enjoy the most. If you enjoy a low-fat diet, then this is your answer. If you like higher fat-foods, lower your carbs and you will feel content and be healthy with these choices. You will stick to the plan you have chosen because you like the food. It is a "winning" decision.

And if you're thinking about ADF, my question to you is: If you could eat a little more food than you needed on one day, would you be able to manage eating an extremely small amount of food the next day?

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