Should You Fast for Weight Loss?

Question: Are there any proven consequences from doing intermittent fasting? People who say it doesn't work are the ones who are scared to go many hours without eating, but I've done it and my body has changed a lot for the good. I've been doing it for 2 years and I went from 20 to 10 percent body fat, working out too of course. My goal is 7 percent, which I have no doubts IF will help me get. I have a cheat day every Sunday and then I fast all Monday, so I go around 30+ hours without eating, weekly. Could this by unhealthy in the long term?  

(from reader Julian Navarro) 

Answer: Intermittent fasting—occasionally not eating for up to 24 hours—isn’t harmful as long as you’re healthy. (If you have diabetes or other health issues, talk to your doctor first.) On the other hand, there isn’t anything especially beneficial beyond its simplicity and convenience, says Alan Aragon, Men’s Health weight loss coach. “The thing that worries me about this question is the goal of hitting 7 percent body fat. This is the leanness level of elite professional and Olympic-level boxers, sprinters, and wrestlers. This is simply not sustainable on a permanent basis unless you have been blessed with a greyhound's metabolism or you’re engaged in athletic competition at the elite or professional level.”

So while intermittent fasting might help you hit the 7 percent body-fat mark, don't expect to maintain it—at least by means that are remotely healthy. “Even 10 percent body fat for the vast majority of guys is a highly athletic body composition to maintain,” says Aragon. “There's nothing special about intermittent fasting that will push things further. Sustaining a caloric deficit by whatever means is what causes fat loss.”

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