Ask a Dietitian: When Is the Best Time to Eat for Optimum Sleep?

We are forever hearing that getting enough sleep is super important for our health. A lack of sleep can influence the development of a number of health conditions, from elevated stress levels and forgetfulness in the short term, to increased risk of diabetes or bowel cancer in the longer term. From a nutrition perspective, we know sleep (or a lack of) can alter your hunger and fullness hormones, ghrelin and leptin, respectively. But how can the timing of your meals help to ensure you get a good night's rest?

Our circadian rhythm, which is fundamentally our sleep-wake cycle is closely connected with our digestion and metabolism. Every cell in our body has an internal clock that regulates the timing of multiple physiological processes, including when you feel more sleepy, alert, or moody. These ‘clocks’ are kept in time by a part of the brain that responds to light.

The purpose of these clocks is for the body to be prepared for routine events, such as the arrival of food. It means different bodily processes and systems are prioritised at certain times of the day. You may experience digestive issues as part of jetlag, as the circadian rhythm is thrown out of whack.

Light isn’t the only thing, however, that influences the timing of these internal clocks. Emerging evidence is also showing that the timing of our meals can also alter these clocks in certain bodily systems. What does this mean for our daily eating patterns?

Start the day with a balanced breakfast

We know that our bodies are most insulin sensitive in the morning, which means we can effectively utilise carbohydrates that we consume. This coupled with the fact that we likely have a full day of activity and tasks to complete ahead means that breakfast is a great time to be including some healthy, low GI carbohydrates. Pair this with some protein and healthy fats to help satiety, and of course, colour for the important antioxidants and popyphenols.

Eat enough during the day

A common dietary downfall is not eating enough during the day, resulting in a ravenous appetite in the evening. Quite often this can lead to overeating in the evening, leaving you feeling uncomfortably full. This feeling, along with digestive system working hard, can make sleep difficult. So, a protein-rich lunch is ideal to keep you going into the afternoon, or all the way to dinner.

Consider the timing of your caffeine intake

In the later part of the day, as our body begins to wind down, avoiding stimulants such as caffeine is encouraged. Food and drink such as coffee, black or green tea, dark chocolate, and energy drinks should all be minimised to ensure all caffeine has been processed by bedtime. An ideal caffeine cut-off time for most people would be 2 pm, but keep in mind the processing time of caffeine will differ between individuals.

Consume dinner 2-3 hours before bed

In contrast to breakfast time, we tend to be less insulin sensitive in the evening. Combine this with the fact that we are winding down to go to bed, a smaller, lower carbohydrate meal is probably warranted. Typically, allowing 2-3 hours between your evening meal and bedtime will allow your body to digest your food and contribute to a restful sleep. Having this time before lying down to sleep, can also minimise the risk of heartburn or GERD, as these happen when the stomach has not fully emptied before lying down.

We also know certain foods can aid in sleep. Turkey, for instance is rich in the amino acid, tryptophan, which helps produce melatonin, our ‘sleep hormone’. Magnesium-rich foods such as dark, leafy greens, and nuts & seeds can also be beneficial, as Magnesium plays a role in muscle relaxation and deactivation of adrenaline.

To snack before bed, or not?

Generally speaking, a light snack before bedtime shouldn’t be an issue. And, in fact, it can be useful for those with high energy requirements or high training loads. Dairy products also contain an amino acid, tryptophan, which converts to melatonin, our ‘sleep hormone’, in the body. For those having trouble sleeping, herbal tea, such as chamomile, which tends to have a calming effect, can be helpful.

Maintaining consistent meal timings helps maintain consistent energy throughout the day, minimise the risk of evening over-eating, helping to ensure we get a good night's rest.

Explore more content like this in our series, Ask a Dietitian.

Health & Performance Collective is the brainchild of Sydney Dietitians Jessica Spendlove and Chloe McLeod. They use their 20 years of combined knowledge and skills as dietitians to work with motivated people to live and perform at their best.

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