The Connection Between Nutrition and Sleep


Nutrition and sleep are integral and intertwined to good health and well being. I’m sure we can all admit we’re a bit grumpier when we have a bad night’s sleep. Poor sleep can affect concentration, mood and hunger cues.

Sleep expert and Neuroscientist Matthew Walker, author of ‘Why We Sleep’, explores how alcohol, caffeine, pharmaceutical stimulants and sedatives disrupt sleep cycles and degrade the quality of brain waves that promote the rich slumber we all need. Walker calls alcohol and caffeine ‘the enemies of sleep’.

He describes the effect a lack of sleep has on our blood sugar: In studies our cells become less responsive to insulin, the hormone released in response to glucose, resulting in high levels of sugar in the blood.

When we lose sleep, we also become more susceptible to weight gain. This is mostly due to decreased levels of our satiety-signalling hormone leptin, and increased levels of hunger-signalling hormone, ghrelin. This makes us feel hungrier (possibly even hangry) and not satisfied when we do eat, which, for those on a weight loss journey is far from ideal.

nutrition and sleep


There are two types of carbohydrates; complex carbs and simple carbs. The complex carbohydrates contain fibre and the hull of the whole-grain contains important vitamins and minerals. Examples of complex carbohydrates are sweet potatoes, pumpkin, brown rice, whole-wheat pasta/bread, oats, rye and buckwheat.

Our bodies take a long time to break down complex carbohydrates, and they help with serotonin release, which both benefit sleep.

Simple carbohydrates (the ones we should consume in moderation) are found in sugar and processed foods. These simple carbohydrates spike your blood sugars, which lead to cravings, a higher level of hunger throughout the day and can be the culprit of a bad nights sleep.

This is particularly apparent when they are eaten four hours or less before bed time. Too much sugar and processed carbs get absorbed quickly and can result in frequent wakings throughout the night.

Mind your carbs (or more specifically the type or carbs) before bedtime – they make the difference between sound sleep and interrupted restless sleep!


In several studies, having an optimal protein intake was associated with less difficulty falling asleep, less difficulty maintaining sleep and less non-restorative sleep.

Basically meaning, if you’re getting a good amount of protein in your diet it will help promote quality sleep. Good protein sources include lean meats, fish, beans such as chickpeas, lentils, black beans, and nuts and seeds.

How can Tryptophan help to support a good night’s sleep?

Tryptophan is an amino acid which is the precursor to our feel good neurotransmitter, Serotonin. Serotonin is then converted into Melatonin, which is well known as our sleep hormone.

Tryptophan rich foods include turkey, fish, eggs, dairy, bananas, nuts, seeds, tofu, tempeh and lentils. Having these foods in your diet acts to support your production of both Serotonin and Melatonin, helping you get a restful night’s sleep.

nutrition and sleep

Caffeine and Sleep

Ever been lying in bed and had the realisation you can’t nod off because you’ve had one too many lattes that day? Not surprisingly, caffeine can have a very disruptive effect on your sleep, after all it’s a stimulant.

Caffeine has a half-life of about 5 hours. So, someone who consumes 40 milligrams (mg) will have 20 mg remaining in their system after 5 hours. This is why i’s best to get your caffeine fix in the morning- ideally before around 1pm as it needs time to metabolise out of your system.

You may be a fast caffeine metaboliser or a slow metaboliser. You will definitely be able to tell this by how quickly you fall asleep on certain days where you have had more coffee than usual.

Read the full article here from GP Nutrition

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