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The #1 Worst Intermittent Fasting Mistake, Dietitian Says

Healthy wisdom that could change how you think about your fasting windows!

Let's be honest: Intermittent fasting is not for the faint of heart. It takes strategy, commitment, and a hefty dose of willpower… but now, a registered dietitian is sharing a new way to think about what your body needs, plus four tips to make your intermittent fasting practice healthier, and more successful for weight loss.

Mandy Enright, MS, RDN, RYT is known for the practical advice she shares on her social media to make weight loss and healthy eating less restrictive and more sensible. This week on her LinkedIn profile, Enright proposed: "Let's talk about the #1 mistake people are making with Intermittent Fasting." But she didn't stop there, and shared some other smart I.F. pointers.

Keep reading to learn Enright's perspective-shifting insights, and check out The Best Oatmeal Combinations for Faster Weight Loss, Says Nutritionist.

"Most people need more than an 8-hour window."

intermittent fasting

Enright kicked it off by calling out what she says is the worst mistake people make with intermittent fasting: Eating within "feasting" windows that are too narrow of a timespan.

She said that the 16-hour "fasting" window combined with the eight-hour "feasting" window may be too strict for some dieters. In fact, she suggested, when your body is telling you that it needs to eat, fighting that feeling "is simply just torturing yourself," and can be compared to forcing yourself to wait 16 hours to use the restroom.

When you think of it this way, you might agree that it's important to listen to your body, right? Here was Enright's solution for going about this more gently—"After all," she said, "would you only let yourself go to the bathroom between 12-8pm? [sic]"

Widen the window.


"If you're looking to try Intermittent Fasting," the dietitian said, "don't be so restrictive off the bat or you will set yourself up for failure."

Instead, she shared: "I always recommend starting with a 12-hour window in your day to start, and you can always adjust from there based on hunger, energy levels, and what your schedule looks like that day."

 One Surprising Side Effect of Intermittent Fasting, New Study Says

Another big intermittent fasting miss…


Enright added that another way she sees people not getting the most out of their efforts is to respond to long daily periods of deprivation by doing this: "If you're only eating 1 or 2 overly large meals per day, how is this helping your weight loss or weight management goals? . . . often I see people eating these big meals super late in the day."

What's the problem with this approach? "Not only is this not ideal for your energy and metabolism, but it's also fast track to a terrible night's sleep," Enright said.

 This Is Why Peanut Butter May Help You Get Better Sleep, Research Suggests

Try these three tips to eat correctly during your "feasting" window.


Enright says instead, dieters should follow these three rules:

  1. Eat earlier
  2. Eat often
  3. Eat balanced portions.

Get on board with the latest healthy weight loss and wellness findings here:

Krissy Gasbarre
Krissy is a senior news editor at Eat This, Not That!, managing morning and weekend news related to nutrition, wellness, restaurants and groceries (with a focus on beverages), and more. Read more about Krissy