How Too Little Sleep can Cause Weight Gain

Did you ever pay attention to how much you sleep, how rested you feel upon waking and if you wake up during the night?

All of this can tell you a lot about your sleep quality and if there is room for improvement.

You already know that your sleep is compromised, if you need medication or supplements to fall asleep. Your body’s natural sleep rhythm is out of sync and can contribute to many chronic health conditions.

There may not be an obvious link between sleep deprivation and your weight, but more and more research is showing just how important sleep is for your mood, mental performance, overall health and wellness, and especially when it comes to maintaining a healthy weight.

Many studies show that people who have a short sleep duration simply weigh more. And, in fact, as the levels of chronic (long-term) sleep deprivation have increased over the past 50 years, so have the growing epidemics of being overweight or obese. And there also seems to be a consensus now, that a lack of sleep is a direct risk for weight gain and obesity.

Let me say that again, a lack of sleep is a direct risk for weight gain and obesity.
So you have a marker right there where you can measure if this might be behind your stubborn weight.

One large analysis of 45 studies which included over 600,000 people says, “studies from around the world show a consistent increased risk of obesity amongst short sleepers in children and adults.” The increased risks were 89% for children and 55% for adults.

The overall data in that study suggests that a reduction in one hour of sleep per day, would be associated with about 1.4 kg in additional weight.

Right now, 40% of American adults say that they get less than 7 hours of sleep per night, and 7 hours is the minimum recommended nightly sleep, with 9 being the maximum.


One way to find out if your sleep habits impact your eating, is to observe if you eat differently on days with little sleep or days you don’t feel rested vs. days where you had plenty of rest and feel energetic. Find out by keeping a food/sleep diary to gain clarity.

Overall, there are two main ways (with two factors each) that we think that lack of sleep contributes to weight gain and obesity.

First, it increases calorie intake in two ways.
● It allows more time available to eat; and
● It messes with your hunger hormones.

Second, it decreases your ability to burn off calories in two ways.
● It can slow your metabolism; and
● It can cause fatigue and, therefore, reduced physical activity.


So if you feel tired, sluggish and have metabolic disturbances, think thyroid and adrenal health, getting your sleep back on track might be your missing puzzle piece.


Let’s talk about all four of these factors I just mentioned a bit more in detail:


Some researchers suggest that the longer the time you’re awake, the more opportunity you have to eat or more specifically, to snack. In fact, some studies have shown that these tend to be nighttime snacks.

And guess what many sleep-deprived people tend to snack on at night?

You guessed it… high-fat, sometimes high-carb, and less protein and fibre snacks. Potato chips or chocolate anyone?

Which, of course, can lead to weight gain.

And, at least one study shows that eating at night increases the time it takes to fall asleep. Especially for women. So there is a bit of a “vicious cycle” in play here.


Many people who sleep less tend to eat more calories throughout the day. And not only due to increased time available for snacking, but also because of how lack of sleep can mess with the hormones that control both hunger and appetite.

How does this happen?

This is a “double-whammy” because some studies show that lack of sleep not only increases the stomach’s hunger hormone “ghrelin” (making you hungrier), but it also decreases the fat tissue’s fullness hormone “leptin” (making you feel less full).

These changes can clearly lead to more eating, and eventually weight gain or even obesity.

It’s possible that this is a natural mechanism that our body uses to make sure we get enough food for longer waking times. But this doesn’t always serve us well, as it tends to make us “overshoot” our energy needs and take in a bit more than we actually need.

Maybe we think that by eating more we can create more energy which we crave, since we feel so tired. Grazing the kitchen and fridge often happens when we are more tired; have you noticed?


Research is just emerging on this topic, but it seems to show that sleep deprivation can lower your “energy expenditure” and body temperature.

This means that your body may naturally burn less fuel at rest during the days when you’re sleep deprived.

When you burn less, you store more.

When we think of energy expenditure and body temperature, we also see the link to the thyroid and the adrenals. The thyroid helps regulate the body temperature and the adrenals help regulate the energy expenditure. So there is another puzzle piece when we are dealing with thyroid and adrenal health.


You know how tired you feel after not getting enough sleep, don’t you?

This is the fourth way that lack of sleep affects weight.

With increasing fatigue, sleep deprivation can reduce the motivation to exercise.

And when you’re burning less fuel at rest (slower metabolism), and are less likely to exercise, you’re at risk of gaining weight. We already knew that one, didn’t we?

So what can we do?


Lack of sleep is considered a “modifiable risk factor”.

This means that, although it increases our risk for obesity, we have some power over it.

How well you sleep and how much sleep you get, is something that you can improve by putting into place some tips and making them regular habits.

So let’s look at what we can do, shall we?



1.  Make sleep a priority.

Let’s admit that, for a lot of us, the lack of sleep we’re getting is often because we simply give other activities priority. Making something a priority will help you achieve it. One way to help with that is to schedule it into your day. Set reminders on your phone when your bedtime routine starts and act upon it.

2.  Be consistent with your sleeping times.

Yep, this is a big one. Having a consistent bedtime – even on weekends, is key. Starting as early as 9:30 pm can do wonders for your recovery. Your body loves routine, and having a consistent bedtime can actually train your brain, your body’s clock (circadian rhythm) and sleep hormones to follow suit. Make sure you are not taking sleep medications if you want to balance your circadian rhythm. Also please be patient, it might take a few weeks until your body catches on to these changes, so don’t feel discouraged but keep going to bed at the same time every day.

3.  Eliminate stimulants after noon.

Ideally, you won’t expose your body to chemical stimulation for the whole afternoon and evening. This includes caffeine (coffee, black and green teas, chocolate) and nicotine (cigarettes). Also think of caffeinated soft drinks like coke, pepsi, energy drinks etc. as well as their light/zero etc. versions.

4.  Get some exercise and sunshine during the day.

Of course exercise and sunshine have many health benefits. They also tell your brain that it’s daytime, so it can help to set your body’s clock. Have some sunlight exposure right after waking up. Step outside for a few minutes and expose your eyes to light. This will signal your body what time of day it is to help regulate hormones.

Tip: Be sure to finish exercise at least three hours before bedtime, as it may stimulate some people and keep them awake. Exercising in the morning or around lunch time is ideal for most people, but late afternoon like 5 or 6 pm might work as well.

5.  Stop eating and drinking a couple of hours before bed.

By cutting out your bedtime snack you will eat fewer calories, and you may even have a better night’s sleep and wake up more alert. Also, by not drinking fluids a few hours before bed you’ll reduce the need to go the bathroom in the middle of the night. This way you also avoid drinking alcohol later in the evening which impacts the quality of your sleep as well.

6.  Lower your lights when the sun goes down.

If your brain thinks it’s daytime it will not make the sleep hormone melatonin so it can stay awake. So, having bright white (or blue-ish) lights can trick your brain into thinking that it’s daytime.

Dim your lights, buy amber/red light bulbs and/or blue-blocker glasses, turn off electronics (or at least use the f.lux or twilight apps), and if you do need to go to the bathroom during the night, don’t turn on the light.

7.  Create a relaxing pre-bed routine.

Choose something that you enjoy and will help to relax your body and mind and prepare it for a good night’s sleep, whether it be a warm bath, essential oils, bedtime yoga or reading a book.

And when you start feeling drowsy, just go to bed.

8.  Keep your bedroom comfortable.

Having a room that is too hot, bright or noisy can keep you from having a good night’s sleep. Ideally your room will be cool, completely dark and either silent or with white noise. Use a sleeping mask if you can’ t get your bedroom to be pitch black.

I’d love to hear from you if these tips are helpful for you for getting a deep and restful sleep. Drop me a line and let me know!


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