Nearly a third of Kiwis don’t get enough sleep, and for people aged between 35 and 49, that figure rises to a whopping 42%. Whether you’re aiming to lose weight, consistently eat clean or improve your fitness, a lack of sleep can make it hard to achieve your goals. Here’s what happens when we’re lacking sleep.
We make bad decisions
Skimping on sleep dulls activity in your frontal lobe, the part of the brain used to make decisions and control impulses. It also amps up activity in your brain’s reward centre, so sugary and fatty treats taste better. All of this makes it really hard to say no to a piece of caramel slice with your morning coffee.
We feel hungrier
Appetite is influenced by two hormones, leptin and ghrelin. Leptin decreases appetite, so when leptin levels are high, we feel fuller. Ghrelin, on the other hand, makes us feel hungry. Sleep restriction revs up ghrelin production and decreases leptin, meaning we feel hungrier, just because we haven’t slept well enough.
Our metabolism slows
Too little sleep triggers your body to produce the stress hormone cortisol, which slows your metabolism to encourage your body to conserve fuel. One study found that when dieters cut back on sleep for two weeks, they lost 55% less fat, even though they were eating the same amount of calories. If you’re limiting your calories, a bad week’s sleep could be countering all of that hard work.
You might be feeling pretty exhausted if you’re not sleeping, but it’s important to keep exercising. Exercise has a positive effect on appetite, reducing ghrelin and increasing insulin sensitivity, so it counters some of the damage done by bad sleep.
To stay as healthy as possible, make sure you’re eating right, sleeping well and exercising regularly. If you’re not getting enough zzzzs, check out our post on foods that can help you sleep.