How Does Sleep Affect Weight Loss?

A question asked by many people looking to lose weight is how does sleep affect weight loss? Let’s look into this topic in more detail below.

Sleep is a vital factor for almost every aspect of our health including weight loss. You can be doing all the right things for your weight loss goals, but if you are not getting enough rest your progress will be disrupted. 

When we fail to get enough sleep our hormones are disrupted from their regular cycles. A recent study has shown that when we sleep for less than 6 hours per night the areas of the brain associated with hunger are activated. It has also been reported that people who frequently miss out on sleep consume around 350 calories more throughout the day.

Sleep deprivation causes the abnormal functioning of the main hormones associated with hunger. These are Leptin and Ghrelin.  


This is a hormone known as the ‘hunger hormone’ Its role is to regulate our appetite and tell us when we are hungry. Unfortunately, sleep deprivation results in the production of too much ghrelin in the body. This results in increased feelings of hunger and increased chances of overeating throughout the day. This has a knock-on effect on your weight loss goals.


This is a hormone that regulates satiety. When we are sleep deprived the body ends up producing low levels of leptin, which makes us think that we need more energy to function. The result is an increased feeling of hunger and a higher potential for overeating. The foods consumed when we often feel increased levels of hunger are carb rich foods like bread and pasta.

The effect of having disrupted levels of both Leptin and Ghrelin is that we find it hard to make the right decisions throughout the day that support our weight loss goals.

To make matters more complicated, not getting enough sleep also causes increased feelings of tension and stress. Stress causes cortisol levels (stress hormone) to rise which in turn, sends signals to the body to store calories as fat.

As well as disruptive hormones there is also the obvious fact that a lack of sleep leaves you feeling tired and low. As a result, you are more likely to skip gym sessions or train at poor intensity.

Most people do not know how much sleep they really need. As a result, they often go to bed late and actually become accustomed to feelings of fatigue during the week. A good way to gauge how much sleep you really need is to take a note of the time you go to bed and wake up without an alarm clock going off. For optimum results, try this little experiment the next time you have a holiday planned. By taking note of the times you go to sleep and wake up over the course of multiple days you give yourself a much more accurate idea of just how much sleep you need.

We will be looking at ways to improve sleep in the next post but for now, if you have any more questions

on how does sleep affect weight loss please contact us.