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The science behind cheat days

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We know all about cheat days. In fact, we use them all the time to justify poor eating choices. “I can eat this, it’s fine. Today will be my cheat day and I’ll start my diet strong tomorrow.” Sound familiar?

the truth about cheat days, how often we need them, and how we can indulge in our favorite foods without keeping us from our goals and helping us reach them instead.

Some people believe that a cheat day is necessary to prevent your metabolism from dropping due to entering “starvation mode” from dieting. But this is not entirely true & it actually may be keeping you from losing weight!

After a TON of research, I found out the truth about cheat days, how often we need them, and how we can indulge in our favorite foods without keeping us from our goals and helping us reach them instead.

The big concern is your resting metabolic rate(RMR). When we diet, we decrease our caloric intake to create a calorie deficit and to lose weight.

Does this cause your metabolism to slow? Yes. There are two ways your metabolism will slow when dieting and for two reasons. One, you lost weight. When you weigh less your body needs less energy (calories) to function at rest. This means your RMR is now less than it was at your original, higher weight. The second type of metabolic slowdown happens long term. This is the one that concerns people and is why cheat days were invented.

This metabolic slowdown occurs due to caloric restriction over a long period of time. Your metabolism adjusts to the lower caloric intake and enters “starvation mode,” in other words, your body starts reducing the rate at which it uses energy to compensate for the lack of calories you are eating. BUT this actually only happens long term (source). The Pennington Biomedical Research Center found that this doesn’t even occur until month 3 of a restrictive diet (source) and the lower RMR can be held off until month 6 if you combine diet with exercise (source). Furthermore, if you diet AND exercise the drop in RMR is lower than those who JUST diet (source).

So what does this all mean?

Having a cheat day every week is unnecessary.

The theory behind a cheat day is that it can boost your metabolism by increasing levels of leptin, the hormone responsible for sending hunger messages to the body. When adding in a cheat day it is supposed to trick your body into thinking that you are not on a restrictive diet at all so it’s okay to burn through those fat stores because it thinks you’ll replenish them later with more food. This way your metabolism doesn’t decrease. But if you are just a few days into your diet or not following it to the letter, this isn’t even necessary.

The only way your body would ever enter “starvation mode” this early in a diet is if you were actually starving; if you decreased your caloric intake far below what is considered “healthy.”

In fact, Jillian Michaels recommends not lowering your caloric intake below your RMR at all, but rather creating that calorie deficit required for weight loss through exercise alone (“Making the Cut,” p 10).

the truth about cheat days, how often we need them, and how we can indulge in our favorite foods without keeping us from our goals and helping us reach them instead.

Should we cut out cheat days?

Yes and no. First let’s think about what a cheat day really is. It’s basically a free-for-all day where we allow ourselves to eat anything and everything our “diet” doesn’t allow. While this can be good to mentally destress from your diet and gear you up to keep going strong the following week, it can do more harm than good. When your cheat day incorporates a lot of high-fat foods your leptin levels drop for up to 24 hours (source), reducing your metabolism and making it more likely to retain those added calories as fat. BUT Leptin levels rise when your added “cheat day” calories come from carbohydrates causing your metabolism to increase. This is the goal!

When the bulk of the calories on your diet break come from carbs and you limit your fat intake, it is actually called a refeed day. Incorporating refeed days regularly can be a way to prevent that metabolic slow down at the 3-6 month mark because it refills your glycogen stores regularly (which are often depleted from low carb diets) so your body never enters “starvation mode” and your leptin levels begin to normalize.

How often should I refeed?

That depends. Basically, the leaner you are the more often you can take a refeed day. The Lean Muscle Project recommends having a refeed day once every 2 weeks if you are over 20% body fat and once a week if you are less than that.

The goal with a refeed day is to increase your caloric intake by about 30%, limit your fats, and still make sure you’re getting in that protein. So this is a more calculated approach to a cheat day. This way you can still indulge, but not hinder your progress.

So, will I ever get to eat cheesecake again?

Yes! We are anti-weekly cheat day, but we’re all for enjoying life. Who wants to live with a diet that is restricted FOREVER?! Not us!

when should i have a cheat day and why- We love guilt-free cheating on holidays and special occasions

We love guilt-free cheating on holidays and special occasions. That is when we enjoy those especially fatty foods that wouldn’t benefit us on a refeed day. Why? Because everything in moderation right? As long as you’re not cheating weekly it really shouldn’t be a big deal.

Another tip: Keep it to a cheat meal if you can, that way you don’t go overboard and gain 5 pounds in one day! Which can actually be pretty easy to do especially if you’re eating out for every meal. Have you looked at some of the calories on those restaurant meals?! Yikes!

So I can’t have fat until Thanksgiving?

Not necessarily. Have you seen our Chicken Florentine Crepes recipe? We use full-fat hollandaise on that baby and we don’t feel guilty about it! If you’re having a particularly strong craving and you just can’t deal, then make some room! Your body needs fats to function properly. So if you want a high-fat meal at breakfast decrease your fat intake for the rest of the day. If we’re having those crepes for dinner, then we do egg whites in the morning and use lemon juice instead of salad dressing on our salads. You can “indulge” weekly as long as you are smart about it and plan out your meals so that you don’t go over what your body needs to lose the weight.

We enjoy our diet, that means we do allow ourselves treats sometimes even daily! We just adjust the rest of our meals around it so that it doesn’t set us back. This way of eating is called IIFYM (flexible dieting) and is very popular among body builders and the fitness community in general.

the truth about cheat days, how often we need them, and how we can indulge in our favorite foods without keeping us from our goals and helping us reach them instead.

Aditi Wardhan Singh

Monday 29th of October 2018

This is so infomative. I had read about Jillian's take on it but this was very well written adding to her thoughts. I'm certainly in need of a diet and cheat days as well. Haha! But in all seriousness, I learned a lot through this post.

Lexi @ That Fit Fam

Thursday 8th of November 2018

Thank you! I learned a lot researching for this post! I always have to know the "why" behind everything, so I'm glad it helped someone else too! =)

Erin @ Stay at Home Yogi

Sunday 11th of September 2016

What a great and informative post - thank you! I like to try doing cheat meals or just a treat instead of full cheat days. Because once I declare a cheat DAY, it's usually all downhill, lol. :) I had my biggest weight loss success when I cut out the weekly cheat day, so I know your advice here is solid.

Lexi @ That Fit Fam

Monday 12th of September 2016

Thank you! I definitely agree! Cheat meals/treats are the way to go. When I used to do cheat days, I would go all out and buy tons of snacks that I really could finish in one day so a cheat day would quickly turn into two lol I made zero progress toward my fitness goals back then lol thanks for visiting!


Saturday 10th of September 2016

This is so interesting. Slightly depressing because I love my frequent cheat days, but good to know, haha!

Niki @ Toot's Mom is Tired

Friday 9th of September 2016

Wow that's fascinating! I knew that a cheat day here and there was actually a good thing but I never really knew the science behind it. Thanks for sharing!

Lexi @That Fit Fam

Friday 9th of September 2016

thank you! I'm glad you liked it! thanks for stopping by =)

Jen @ Saving with Spunk

Friday 9th of September 2016

I'm all about working out to create caloric deficits. I never feel like I'm missing out and making exercise a habit is key for long term healthy living. This is a great read. Thanks!

Lexi @That Fit Fam

Friday 9th of September 2016

I'm with you! I get my deficit from working out. I like eating too much to keep cutting calories ;) And you're right. exercise is key. Having a strong, capable body is so important! thanks for stopping by!

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