Intermittent Fasting and Sleep

Sleep is essential for boosting mood, creativity and even your sex drive yet despite it’s importance, so many of us seem to be cutting corners and prioritising our screens late at night. Some have gone so long without a decent sleep routine that they’re not quite sure where to start. But, hope is not lost and intermittent fasting may just be your answer!

The importance of good sleep 

Getting good quality sleep is similar to booking your brain into a spa; it rebalances hunger hormones, soothes the nervous system, restores insulin sensitivity, prevents junk food from triggering excessive reward-circuits, and even helps to focus your sense of self.

Sleep is just as important in achieving a healthy lifestyle as diet and exercise. Yet, it’s commonly overlooked or avoided in everyday life with upto 35% of adults not getting the recommended amount of 7 – 9 hours of sleep each night. 

Not only this, fewer hours of sleep has been scientifically recognised to increase the risk of obesity by 41%. Reasons for this include elevated levels of the hunger hormone, ghrelin, after a poor night’s rest, lack of motivation to exercise and an increased craving for fatty, salty foods. So, if you’re looking at lifestyle changes, your sleeping habits should be considered too!

Intermittent fasting and sleep

One method for improving your quality of sleep is by beginning the practice of intermittent fasting. And the good news, research suggests that it won’t take long before you notice changes; participants in a 2003 study found improvements in just one week. 

This particular study, which measured sleep using a polysomnography before and after 7 days of fasting, found that fasting short-term can reduce restlessness, awakening throughout the night and leg movement during sleep. Benefits were also seen during the day with improved concentration and emotional balance. 

Healthy sleep can also be compromised by overeating during the day and into the evening, but going to bed with a relatively empty stomach (which happens when you extend your fasting window) enables internal clocks in your digestive system to align with the clock in your brain so all your systems agree to go offline for sleep. Intermittent fasting also causes levels of the sleep-promoting hormone, melatonin to rise, which can help you fall asleep faster and stay asleep longer. Intermittent fasting also promotes the release of human growth hormone, one of your body’s vital resources for repairs while you’re asleep.

In a 2019 study, run by scientists from the Salk Institute, overweight volunteers who restricted their eating to a 10-hour window (14:10) lost an average of 3.3kg over the course of 12 weeks. They also saw big reductions in waist size, blood sugar levels, blood pressure and “bad cholesterol” levels. Last, and by no means least, most of them also enjoyed longer and less interrupted sleep.

What is intermittent fasting?

There are various methods of intermittent fasting, two of the most common and practised on The Fast 800 are TRE (time-restricted eating) and The 5:2 diet. 

TRE is the method of reducing the time window in which you consume calories to a maximum of 12 hours. The most popular timings are 12:12 (12 hours fasting, 12 hours eating), 14:10 (14 hours fasting, 10 hours eating) and 16:8 (16 hours fasting, 8 hours eating). Within a fasting window, it’s important to still drink plenty of water and you can also enjoy black coffee or tea without worrying about breaking your fast. 

The 5:2 method of intermittent fasting consists of lowering your calorie intake to 800 calories for two days each week and eating with no calorie restrictions, just a balanced diet for the remaining five days. We recommend following a Mediterranean-style diet for maximum nutritional benefits. 

If you’re completely new to intermittent fasting, our Online Programme offers meal plans available for those looking to follow a 5:2 pattern of eating, as well as meal plans for rapid weight loss and weight maintenance. We now also have meal plans available for those looking to eat two meals a day, great for those looking to try 16:8 fasting!

With a library of learning articles and a dedicated TRE & fasting group in our interactive Community, with advice from our expert Health Coaches, you can feel confident you’ll receive any answers you’re looking for on the Programme. If you want to give it a go, our 7 day free trial is a good place to start. You can learn more here.

Practical tips for implementing fasting into your lifestyle

• Gradually build up your fasting window – if you’re new to time restricted eating, it may help to start with the 12:12 method (fasting for 12 hours, eating for 12) then when you feel confident, build to 14:10 or 16:8. We often find that 14:10 is the most sustainable method long-term. 
• Fill your cupboards with herbal teas – a great way to settle your sweet tooth if you’re partial to a pudding each evening. Just be conscious that some teas have caffeine in them so be sure to avoid late at night. 
• Eat plenty of protein – the meal you eat should be high in protein, particularly when breaking your fast. Here are some high in protein and fibre foods to break your fast. 
• Consider a supplement – when fasting, some people miss out on essential nutrients, if their meals are not planned precisely. On The Fast 800 Online Programme, our in-house nutritionist ensures that all meal plans hit our nutritional targets; however, if you’re doing the calculations yourself, you may wish to safeguard your nutrition with a good quality Multivitamin. If you’re in the UK or Australia, you can purchase The Fast 800 Multivitamin here.