Your Guide to Sleep and Fat Loss

Sleep Fat Loss

We all know getting enough sleep is crucial for good health and general well-being. But are you aware that sleep deprivation interferes with fat loss and can cause muscle wasting? Yes, it really does. 

So, this article will tell you why sleep is essential for losing fat and keeping it off. Besides, you’ll discover eight powerful tips to help you sleep like a log tonight and every night from now on. 

Not only will you feel an inflow of energy, but you’ll also be more successful at shaping a head-turning figure. Let’s dive in!

Does Sleep Affect Fat Loss?

Yes! And it does so to a significant degree. Sleep is one of the most overlooked factors in the fitness world. Failing to get enough of it affects not only your health and well-being but your body shape as well.

One meta-analysis (based on 634,511 participants) found that adults with poor sleep are 55% more likely to become obese [1]. In children, this rises to a whopping 89%. 

Why’s that? Because sleep deprivation increases hunger and food intake [2]. It does so by changing brain chemistry. The “satiety hormone” leptin decreases while ghrelin, the hunger hormone, rises [3]. 

As a result, you’ll feel hungrier and eat more. This increase in food intake tends to happen in the evening and late at night, usually involving a junk food binge [4-6]. The reason is that sleep deprivation weakens willpower and can thus lead to unhealthy food choices. 

Poor Sleep Prevents Fat Loss and Causes Muscle Wasting

Not only does shortage of sleep affect body weight, but it causes an increase in body fat and a reduction in muscle mass.

A study published in Annals of Internal Medicine evaluated the effects of sleep deprivation on dieting subjects [7]. 

For 14 days, overweight adults were split into two groups. The first group was instructed to sleep 8.5 hours a night, while the second slept only 5.5 hours. Throughout the study, all subjects maintained a moderate calorie deficit. The final results were remarkable!

While both cohorts lost a similar amount of weight, those who slept 8.5 hours lost more than two times as much fat (1.4 kg vs 0.6 kg). They also retained far more muscle tissue. In fact, 80% of the weight loss in the sleep-deprived group came from lean body mass!

While this happened for various reasons, one of them is that sleep deprivation raises cortisol levels while decreasing testosterone [8-9]. This, in turn, increases the chances of muscle wasting and fat gain.

How Much Sleep Do You Need?

As we’ve seen, it is crucial to get enough sleep, not only to optimise your health and well-being but also to shed fat and keep it off. But how many hours of sleep do you need? 

Well, the National Sleep Foundation recommends 7 to 9 hours per day. While that’s a good general guideline, whether you should aim for the high or the low end of the range depends on two main factors. 

First off, there’s your genetic makeup: some people need more sleep due to specific genetic mutations. (Some individuals are also more affected by sleep deprivation than others [10].) This genetic part is something you can’t control – you have to play with the cards you’ve been dealt.

The second one is sleep quality. This is an area where you do have a high degree of control, as we’ll see in a minute. If your sleep quality is excellent, you’ll need fewer hours a night. But if you sleep poorly, you might still feel tired after getting what should be enough shuteye. 

So, the optimal number of hours varies among individuals. It even varies on a day-to-day basis, which is down to different factors. Strenuous physical activity, for example, raises your sleep requirements.

That said, you know best how much sleep you really need to feel well-rested and function properly. If you wake up groggy every day, common sense says you need more sleep than you’re getting.

Let’s Get You Sleeping Soundly Tonight

Besides the number of hours, the quality of your sleep also matters. Here are eight proven tips to help you sleep better tonight and beyond.

1. Turn Off the Lights

Light exposure, particularly to blue light, impairs the secretion of melatonin – the hormone that regulates sleep and wake cycles. That is why it’s harder to fall and stay asleep with the lights on. 

So, block completely the light in your room. If that’s not possible, use a sleep mask.

2. Avoid Blue Light Exposure Before Sleep

For the reason explained above, avoid blue light exposure before going to bed – it interferes with sleep. 

This is because blue light tricks your brain into believing it is daytime. It impairs melatonin secretion, making it harder to fall asleep [11-12].

It’s important to note that white light – like that of lamps and electronic device screens – contains a mixture of different wavelengths. A lot of it comes from blue light [13]. 

That’s why it is best not to watch television, work on your laptop, or browse on your phone before hitting the sack. If you want to keep using those devices, we recommend using glasses or software that block out blue light.

There are various apps available to help you out here. A good option for a laptop and an iPhone is F.Lux. If you use an Android device, the Twilight application offers a solution.

3. Stick to a Fixed Sleep-Wake Schedule

An irregular sleeping pattern hurts sleep quality by impairing melatonin release [14-15]. So, try to go to bed and wake up at the same time each day.

4. Keep Cool

Increased body and bedroom temperatures promote wakefulness and affect sleep [16-18]. That’s why it is hard to fall asleep on a hot summer evening. 

While the optimal bedroom temperature differs for individuals, the National Sleep Foundations recommends setting the thermostat at 18 degrees Celsius.

5. Don’t Consume Caffeine Late in the Day

Around 90% of adults ingest some form of caffeine daily. And while it is great for improving workplace productivity and boosting gym performance, it disrupts sleep if consumed too late in the day [19].

Since caffeine has a half-life of around 5.7 hours, if you consume 200 mg of it at noon, you’ll still have 100 mg in your system at around 5.45 pm [20]. 

So, to prevent caffeine from affecting your sleep, limit your consumption to the early hours of the day. 

6. Avoid Long Naps

“Power naps” can improve mental performance and aid recovery after a hard workout. But if you over-extend your nap, it can reduce sleep quality during the night by interrupting your circadian rhythm [34-35]. 

Therefore, avoid napping for longer than 30 minutes [36]. Anything beyond that puts you at risk of “sleep inertia” – that groggy feeling that takes time to shake off and disrupts your circadian rhythm.

7. Consume Carbs in the Evening

Eating carbs before bed increases the levels of tryptophan, a serotonin precursor that helps you fall asleep [21-22]. 

So, consume a portion of your daily carb intake in the evening. Around four hours before going to bed is the sweet spot [23]. 

High glycemic index carbs such as potatoes and white rice are most effective at inducing sleep [23]. 

8. Supplement with Magnesium

Magnesium is a mineral that’s involved in more than 600 bodily reactions [45]. Unfortunately, most people don’t get enough of it.

A study published in the Journal of the American College of Nutrition found that 58% of adults fail to get the recommended daily dose. Moreover, 19% even get less than half of the necessary amount [24]. 

This impairs sleep quality because magnesium plays a crucial role in activating the parasympathetic nervous system, which is involved in unwinding your body and brain [25-26]. That’s why getting enough magnesium improves your sleep [27]. 

The foods richest in this valuable mineral are spinach, Swiss chard, dark chocolate, pumpkin seeds, almonds, black beans, avocado, figs, yoghurt, kefir, and bananas.

But even if you consume those foods on a regular basis, you can still develop a magnesium deficiency, especially if you’re a hard-training athlete. Taking a magnesium supplement ensures you have your daily needs covered.

The Bottom Line on Sleep and Fat Loss

If you want to lose fat, don’t focus solely on eating right and training hard, but also make sure you get enough high-quality sleep each night.

Sleep significantly influences your figure, mainly due to its effects on hunger. If you get enough sleep, you’ll experience fewer cravings, and it will be easier to stay on track with your diet.

Besides, getting enough sleep boosts gym performance, prevents muscle wasting, and accelerates fat loss. 

So, use our eight proven tips to enjoy high-quality sleep and shape a fit, eye-catching figure.


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