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Did You Know Lack of Sleep Affects Weight Loss?

Did You Know Lack of Sleep Affects Weight Loss?

If you’ve got weight loss goals for any reason, you know that achieving them can feel so far away. Sure, there’s what you’re putting into your body minus the energy you’re expending out, but did you know there’s something else that plays just as important a role in weight loss?

Your sleep!

Research published in the American Journal of Epidemiology found that sleep-deprived women are a third more likely to gain 33 pounds over the next 16 years than those who receive just seven hours of sleep per night — and of course there’s so many connections between poor sleep to diabetes, obesity, high blood pressure, heart failure… the list goes on. It’s never about the size of your pants, but the way you feel in them, and not getting good sleep won’t help. 


Not sleeping makes you hungrier. 

Missing out on sleep interferes with the normal rhythms of your hungry hormones. Studies show that when you’re sleep deprived, ghrelin (the “i’m hungry!” hormone) increases and leptin (the “i’m full!” hormone) decreases. So even if your body isn’t needing food, it’s going to tell you it wants some. 

You also tend to eat more food. 

One study found that missing a few hours of sleep one night can increase your calorie intake by 500 the next day! Sleep deprivation also makes you select greater portion sizes of all foods, but processed foods especially look more appealing because your brain’s ability to make decisions is impaired. Its response to high-fat, refined, carb heavy food is zinging in its reward center. 

Lack of sleep also makes it harder for your body to recover from your workouts. 

After a rough night of sleep, the last thing most of us want to do is hit the gym. But let’s say we find the superhuman willpower inside of us to go — when you don’t get enough zzz’s, your body slows down the production of growth hormone, which is a natural source of fat-burning and cell regeneration that facilitates recovery. Poor sleep means less slow-wave sleep, which is when this hormone is released. It also means more cortisol, your body’s stress hormone, which also slows down the production of growth hormone. It’s a cycle that only ends with the right amount of rest. 

Even if you’re doing everything “right”  — exercising, keeping calories low — it won’t do much if you’re not getting in those eight hours. 

Sleeping less than seven hours a night can reduce — and even undo! — the benefits of being intentional around food intake, according to research. In a study published by Annals of Internal Medicine, the same group of people were put on different sleep schedules while being on a specific diet. During the sleep schedule where their bodies received adequate rest, half of the weight they lost was from fat. 

However, when they switched schedules that had them cut back on sleep, the amount of fat lost was cut in half—even though they were on the same diet the whole time! 

Losing weight or not, they felt significantly hungrier, less satisfied with their meals, and didn’t have energy to exercise when they didn’t sleep well, which is even more important than any number on a scale. 


So, prioritize your sleep!

Life, jobs, families, a pandemic — these days especially, sleep may feel like last on the list (for some good tips on getting better sleep during these times, click here), but it’s one of the most important things to prioritize for your mental, emotional, and physical health. Seven to nine hours of sleep per night is best for most people, and make sure that on the nights when you don’t sleep well (we all have them!), that it’s not followed up by a few more.