The M&F Diet Guide

Thinking of trying keto? How about intermittent fasting? Before you jump on the next big thing, learn the real deal on the most popular diets.

- Rachael Schultz

CHANCES ARE YOU HAVE A CO-WORKER or lifting partner who praises his or her diet—keto this month, intermittent fasting next, maybe something called the carnivore diet after that. But trying new diets other people swear by can be both exhausting and expensive—so we’ve tapped a handful of nutrition experts to weigh in on whether or not five of the trendiest diets right now are worth your time.

INTERMITTENT FASTING

WHAT IT IS: You eat all your food within a certain window, then you fast the rest of the time. Some types require whole-day fasts, but the most popular— and most practical—is when you fast for 16 to 20 hours, then eat whatever you want in a four-toeight-hour window. Done right, intermittent fasting (IF) will help you lose fat and maintain strength at least as well as counting calories, says a 2017 study analysis in JISSN. THE PROS: “When you have less time to eat, you will eat fewer calories,” says DJ Blatner, R.D., nutritionist for the Chicago Cubs and author of The Superfood Swap. Fasting can also improve your cholesterol and triglycerides and help control disease-causing inflammatory cells and metabolic hormones, and it may even help control insulin levels. IF is also schedule-friendly, since you pick the hours you want to feed and fast, she adds. (If a 16-hour fast freaks you out, start with 12 hours on, 12 off—a kind of IF light.)