Sleep, weight loss and appetite… does lack of sleep make you eat more?

The surprising benefits of sleep for weight loss

Rachael Attard Lean Legs Program – Wednesday Week 7

Sleeeeep! Warm, snuggly, sweet, deep sleep… there’s nothing better. Are you getting enough? Do you have difficulty sleeping? AND, is sleep for weight loss important?

I generally sleep very well. I go to bed super early (like 8.30!) and get up super early (usually 5.30!) and I find that if I stop eating after dinner and read a little before bed I crash out quickly and wake up feeling pretty good.

But… if I snack late, play on my phone too long, get too hot, or even wear the wrong pjs (!), then I don’t sleep so well OR I sleep well but feel like rubbish in the morning (food hangovers are real).

The last few days my work has been super busy and I’ve felt really tired. I’ve been eating a fair bit more than usual, almost as a subconscious, primordial action to try and refuel and re-energise!

My own anecdotal experience suggests that lack of sleep does make you eat more and therefore sleep may impact weight loss. Then, in a creepily uncanny way, Lauren F from the Lean Legs FB group shared some fascinating timely and relevant information about sleep and our appetites and what is really happening in our bodies, check it out:

We all need it, most adults don’t get enough of it.

And it’s key to weight loss and recovery.

Why is snoozing so important?

Sleep deprivation (like alcohol) can lead to impaired judgement making it easier to reach for snacks, it also affects the release of ghrelin and leptin which makes those snacks seem extra tempting, it can also persuade you to reach for larger portions than you would normally. Also like alcohol it can interfere with your insulin synthesis after just a few days making it harder to access that fat to burn during your day.

In a nifty study by the Annals of Internal Medicine, groups of dieters were put on different sleep schedules. When their bodies received adequate rest, half of the weight they lost was from fat. However, when they cut back on sleep, the amount of fat lost was cut in half – even though they were on the same diet. What’s more, they felt significantly hungrier, were less satisfied after meals (This is because of the ghrelin and leptin), and lacked the energy to exercise. Overall, those on a sleep-deprived diet experienced a 55 percent reduction in fat loss compared to their well-rested counterparts.

What happens while you are sleeping?

According to sports medicine, the non-REM sleep phase is when an increase in protein synthesis and the mobilization of free fatty acids happens which helps repair muscles you broke down during your workouts. When you don’t sleep, your muscles can’t fully restock on their energy stores (glycogen). Glycogen is one of your body’s main energy sources during exercise, and when you run out, you may find your endurance will as well. No sleep no muscle repair.

Multiple studies have shown that lack of sleep can lead to faster fatigue, although won’t actually reduce your output in speed, strength and endurance putting you in a place where you can’t give it your all and reducing the effectiveness of your workout. This means you won’t be able to run as fast or as far, and means you might end up taking easier modifications that you would have if you had gotten a solid night of sleep (always take modifications if you need it). Furthermore, a lack of sleep can lead you to be less coordinated than usual leading to the possibility of injury.

We also know sleep reduces the amount of cortisol (stress hormone) that the body produces. Cortisol can lead to weight gain and make fat loss almost impossible. When you’re stressed you’re also more likely to reach for high fat foods because your body wants to store weight because it doesn’t know when you’ll want to call on that weight. Cortisol can also be a major source of inflammation.

How do you sleep better?

Right after drinking enough water, obtaining quality sleep is the best way you can set yourself up for success in life. Sleeping enough and regularly is incredibly important particularly when you’re working out and your body needs to recover. While the average adult needs 8 hours of sleep, milage can vary. Whatever that number looks like to you, let’s talk about how to maximise it.

Reduce blue light exposure a few hours before bed

Blue light can convince your body it’s still day time which can make it harder to fall asleep. This can look like buying a pair of blue light glasses for late night computing, downloading an app on your phone to block blue light or for the ambitious using lights that let you adjust the colour spectrum. The opposite also applies, get natural sunlight while you can with Rachael’s program that might be during your daily walk or runs, but if you work indoors this could look like taking a walk during your lunch hour or bringing your morning coffee outside.


Sweet beautiful coffee. I drink a lot of it, maybe too much of it. What I don’t do is drink coffee around 8 hours before I plan to go to sleep. I’m largely nocturnal so my last cup is between 4-6pm but if you’re a day walker you might want to consider having your last cup around 2pm. Consider things like apples or dark chocolate which have lower amounts of caffeine or can stimulate similar to caffeine within the 6-8 hour half life. While a glass of wine can have great health benefits, try to wrap up any drinking you plan on doing a few hours before you want to sleep. Consuming alcohol can disrupt HGH production, melatonin and leave you with disrupted sleep patterns.

Consistent schedules

Woof. This is a hard one. I work in and manage bars so can get home anywhere between 12.30am and 6am depending on what is happening. Keeping things consistent even on days off is a huge boost to helping you fall and stay asleep, but for me is the hardest. And also, create a dedicated sleep routine, clue your body in as much as possible that this is the time to wind down.

Dedicated space

Keeping your bedroom for sleep and bedroom specific activities can also help remind your mind that this is the place for rest. Keeping your bedroom cooler, quieter and darker than the rest of your home can help a lot.

When you can’t sleep

Try getting out of bed. You can also try a shower or a bath, raising and then lowering your body temperature can help signal your body it’s time to sleep. Try melatonin, magnesium, amino acids (I-theanine and glycine specifically). If you’re more into natural remedies, lavender, valerian root, and ginkgo might be the move.

 Fascinating stuff right! Was I tired because I needed more food or did I eat more food because I was tired?

I still did my workouts but it’s interesting how I can really feel that the extra mental busy-ness at work makes me feel a bit drained. Sleep, weight loss and appetite seem all interlinked (along with other related factors).

What do you do when you can’t sleep? I sometimes do a few breathing exercises if my mind won’t switch off, but generally I find that thinking through things that went well during the day and embracing a feeling of gratitude is a beautiful practice to help set me up for a sweet, deep slumber.

I read some amazing research about the power of gratitude for better sleep and so many other benefits on the Positive Psychology website who quoted studies by Happier Human (2018). Such a simple practice that can change your life, and your outlook on life.

Do you eat more when you are tired? Have you tried practicing gratitude or do you have a sleep routine?

Frequently Asked Questions
What happens if I exercise really hard?

If you exercise harder, faster, longer then your body can adapt to it! Read more about the minimum effective dose.

How do I stop snacking after dinner?

If you find it difficult to stop nibbling after dinner, I’ve got some great resources for you. Read the post here!


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