Does intermittent fasting help with sleep? Find out

5 min readAug 20, 2020
Image Source: Shutterstock, purchased for usage

With constantly evolving dieting trends today, there’s one eating approach that’s increasing in popularity and traces a unique relationship to sleep- intermittent fasting.

Intermittent fasting or fasting on sleep is used by many for dieting, with proponents saying that it does everything from improving your sleep, helping you lose weight to boosting your overall well-being.

In this post, we are going to discuss the concept of intermittent fasting in more detail, along with its relation with how we sleep.

What is Intermittent Fasting?

Practising intermittent fasting essentially means that you chart out a fixed eating schedule and designate regular, specific times when you eat nothing or consume very few calories.

Going into a fasting mode allows your digestive system to rest, giving your body this some time to repair and restore itself at a cellular level. Further, intermittent fasting also triggers the body to use stored fat for energy, making it an effective strategy for your weight loss goals.

Unlike regular fasting where you experience prolonged hunger when fasting for a full day, adjusting to intermittent fasting (fasting on sleep) is relatively easy as you do not have to suppress the eating urge when you’re very hungry. Combined with sound sleep, intermittent fasting has the power to completely transform your overall health.

The Way Intermittent Fasting Works

Although intermittent fasting is often used to describe a broad range of eating patterns, it most commonly describes a mode of eating that allows you to extend your nightly fast by a few hours every day. This type of intermittent fasting is also known as time-restricted eating.

Different individuals use different patterns of intermittent fasting, i.e. eating and non-eating schedules as part of their day to day lives.

Typically, limiting eating to 8 or 10 hours a day allows the body to be in a fasting mode every day in the remaining 16–18 hours.

While some people use a 24-hour fast or two days fasting a week pattern, others opt for restricting calorie intake every 2–3 days, with normal eating in between. This is often known as 5:2 fasting. When you extend your overnight fasting period, there will be a significant decline in your body’s secretion of the hormone insulin and a rise in secretion of human growth hormone.

The benefits of intermittent fasting usually come from these key hormonal changes that occur when you spend extended time in a fasted state. This will lead to desirable hormonal changes when you prolong your overnight fasting to make it lasts between 14 and 18 hours.

So the ideal way to implement intermittent fasting daily is to make sure that you eat your first meal around 6 hours after waking every single day. This will ensure that the intermittent fasting works for you, irrespective of the time you wake up.

Health Benefits of Intermittent Fasting

Among the key benefits of intermittent fasting includes-

  • Strengthening of immune function.
  • Enhanced growth hormone secretion.
  • Increases the body’s ability to fight off certain diseases such as heart disease, diabetes, Alzheimer’s and obesity.
  • Improve mental health and well-being.
  • Aids with the cellular repair which happens when we sleep.

How Does The Science of Fasting and Sleep Work

When you eat continuously during the day and evenings and let the body engage in active digestion all the time, it often creates problems for sleep pattern. Routine intermittent fasting helps the body stay well aligned for sleep in many different ways as discussed below-

  • Strengthens our 24-hour circadian clock

There are studies that suggest how restricting eating to 8-hour or 12-hour windows can lead to various advantages and help us maintain healthy body weight and lower the chances of high blood sugar and diabetes, irrespective of the nutrient breakdown of the food we eat within this time duration.

Further, restricted eating also assists in strengthening our 24-hour circadian clocks, which positively influence our sleep patterns. A balanced and more synchronised circadian clock leads to various advantages such as falling asleep easier, staying asleep and waking up refreshed on a regular basis. Intermittent fasting also brings in consistency and quality in our sleep routine to help us feel and function at our best.

  • Reduces awakening at night

Another study suggests that the timing and the duration of fasting can also influence our sleep patterns and reduce instances of nighttime awakening. Periodic, short-term fasting not only helps us sleep better but decreases our leg movements (which can be highly disruptive to sound sleep).

  • Helps with jet lag

Intermittent fasting also helps with jet lag as not eating for an extended duration of 16–18 hours before you land can help your body clock adjust to a new time zone. So, fasting during a flight while travelling helps you adjust your eating pattern to the local time and reset your internal body clock.

Although there are several benefits of intermittent fasting, doing it for long-term can negatively affect your REM sleep in some cases causing a disturbed sleep pattern. Also, if you are very hungry, then falling asleep gets very challenging and is strictly not recommended.

How to Sleep When Doing Intermittent Fasting

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Different individuals respond to intermittent fasting differently. While some people find it hard to fall asleep or get restless on an empty stomach, others manage it easily.

To have a good night’s sleep when you’re doing intermittent fasting, you need to take care of following things-

  • Be mindful of what you eat as your last meal of the day. For example, too much coffee or alcohol can disturb sleep cycle and make it harder to fall asleep.
  • Intermittent fasting offers its benefits when you are consciously thinking about food for sleep. Focus on healthy food items such as fruits, vegetables and nuts which will give much-needed fuel to your body to feel energized during the day and sleep better at night.
  • Make sure to stay hydrated during the day as hydrated body helps you sleep better at night.

Final Takeaways

Intermittent fasting is a robust dietary tool that can bring in many advantages, including fat loss and reduced inflammation along with a host of hormonal, cardiovascular and metabolic health benefits.

However, in some individuals, it can affect sleep quality under certain circumstances.

While it may seem like a challenge to fast intermittently, if you transition gradually coupled with eating right, intermittent fasting should not impact your sleep. Instead of disturbing your sleep, it should help you sleep more.




Wakefit is a research and innovation driven sleep solutions company founded with a vision to democratize sleep in India.