Whether it’s Keto, Whole30, Paleo, the Atkin’s diet, or the Lemon Detox, there’s always been a popular diet making news in recent years. What’s interesting to observe is how often changes in sleep habits occur with those making lifestyle changes and trying new diets.

As one Whole30 participant noted recently after cutting out morning sugars and caffeine, “I never would have dreamed how much I was propping up my body in the morning with caffeine and sugar, and how much I needed it to perform basic functions.”

To succeed on any diet or weight loss plan, good sleep is critical to sustain energy as the body is adapting to changes. Below are several examples of how good sleep helps to ensure better health, energy and balance throughout the day.

Calories in Versus Calories Out

There’s a simple formula for determining how much weight you will gain or lose in a week. A pound of fat contains roughly 3500 calories of energy, so take the total amount of calories you have eaten and subtract the total number of calories you have burned through metabolism or exercise.

(Calories eaten – calories burned) / 3500 = pounds of body weight gained or lost.

This formula isn’t perfect. The more weight you lose, the more your body goes into starvation mode to reserve tissue. However, it provides a rough guideline. Hormone levels are also essential to signal your body to break down fat instead of protein. Getting adequate sleep keeps your body’s hormones optimal, so you build more muscle and lose fat. How much sleep do you need? For optimal body composition, aim for 7-9 hours a day.

1. Sleep Improves Hunger Hormones

Two hormones play a role in determining how hungry you feel. The first of these hormones is called leptin. When leptin levels are high, your hunger level decreases. The hormone ghrelin acts oppositely. When this hormone is elevated, you feel less hungry.  A study published by K Spiegel in 2004 found that when they restricted men with healthy BMIs to 4.5-5 hours of sleep per night, the participants saw an 18 percent decrease in leptin and 28 percent increase in ghrelin.

  1. Sleep Stops Late Night Snacking

If you stay up late into the night watching TV, you are more likely to snack absentmindedly. It might not seem like snacking will make a difference to your overall body composition, but if you eat half a bag of chips each night, you’ll consume about an extra 600 calories per day.

Set a bedtime for yourself and try to stick to it to stop snacking

  1. Sleep reduces Hunger Cravings

When you get adequate amounts of sleep, you reduce your junk food cravings. Sleep impairment changes the way your reward centers in your brain function, leaving you more susceptible to giving in to junk food cravings.

In a study performed by researchers from St. Luke’s-Roosevelt Hospital Center and Columbia University, the researchers examined the link between junk food cravings and sleep deprivation.

The researchers restricted subjects to less than 4 hours of sleep per night for five nights and then showed them pictures of unhealthy and healthy foods. The sleep-deprived group reported that the junk food looked more appealing compared to a group of subjects who slept up to 9 hours per night.

  1. Less Exercise

When you limit your sleep, you are more likely to skip your daily workout which reduces the number of calories you burn per day. Exercising less also has adverse effects on your hormone profile that led to fat gain.

Imagine you’re already feeling exhausted from staying up to 3:00 am in the morning. Do you think you think you’ll hit the gym after work? It’s much more likely that you’ll go to the gym when you’re feeling fresh.

  1. Insulin resistance

Insulin is a hormone that shuttles blood sugar into fat cells, your liver, and muscle cells. When you sleep less, your insulin resistance increases, your body becomes less efficient at monitoring blood sugar, and you gain weight.

A study published in 2010 by Orfeu M. Buxton et al. found that subjects restricted to five hours of sleep per night for a week had significantly reduced insulin sensitivity. Not only does sleep deprivation have the potential to lead to fat gain, but it can also increase the risk of developing diabetes.



By sleeping adequately, your body will be better able to regulate hunger, and your body composition will improve. Try setting a nightly sleep schedule to force yourself to go to bed at the same time every day. If you can establish a consistent routine, you’ll be more likely to improve your sleep habits long term.

This article has been updated and was originally published in July of 2018