Foods Which Impair SleepHow we live affects how well we sleep. Changing habits that have become part of a busy lifestyle is difficult. We may not even be aware that the foods we are eating are keeping us awake at night. By adjusting what and when we eat it is possible to improve sleep and feel more alert during the day, without the extra coffee!


Caffeine is well known as a stimulant. It is also found in other foods and drinks such as tea, chocolate and soft drinks.

Caffeine raises the levels of the hormones adrenalin and cortisol. It stimulates production of adrenaline which helps keep you active and alert during the day. Too much coffee can make you feel shaky and anxious and interfere with sleep. Studies have shown that coffee drinkers can take twice as long to fall asleep and sleep less, compared to those drinking decaf.

A good night’s sleep depends on the body and mind changing from daytime alertness into night time mode. As night draws in, the body undergoes a number of changes that prepare the body for sleep. Production of the hormone serotonin increases and there is a drop in adrenalin. As it gets darker the body starts to release melatonin which is very similar to serotonin. Melatonin regulates the sleep/wake cycle. Anything that interferes with the balance of these two ‘night’ hormones affects sleep.

Coffee and stress are well known for their stimulating and sleep preventing effects. The effect of sugar is less well known. Sugar affects the levels of the adrenal hormones causing them to rise if blood sugar levels are too low. Raised night time levels of cortisol may also affect tissue repair and speed up the aging process.


Alcohol is a relaxant but unfortunately is best avoided by the insomniac. The initial effect is to switch off adrenalin causing that feeling of relaxation. After a few hours the body starts to adjust and try to regulate the affects. This interferes with the different stages of sleep making you feel tired and irritable in the morning. Alcohol affects the quality of sleep and causes dehydration.

Time to Eat

Many people will be familiar with the feeling of finding it difficult to sleep after a meal. The body is busy trying to digest a large meal making it difficult to relax and fall asleep.

Feeling hungry will also affect sleep. A light snack before getting ready for bed can help sleep. A warm, milky drink encourages relaxation and can help keep hunger at bay. It is debateable whether it is the milk, the warmth, or the habit that is responsible for the relaxing feeling but it is certainly more advisable than coffee, tea or alcohol!

It is advisable to leave at least 4 hours between eating a large meal and going to bed. If it is not possible to eat earlier in the evening, try and keep a late night snack light and easy to digest and avoid foods that stimulate and interfere with sleep. A banana and a glass of milk will get you through the night. A warm drink or snack is more satisfying than anything chilled or cold.

Sleep Stoppers

It is difficult to know what is in some of the food we buy. Caffeine is contained in many drinks and a small bar of dark chocolate can contain as much as a cup of instant coffee!

Fast foods and takeaways are often high in fat and contain artificial colours and flavourings that are stimulating and hard to digest. Foods that are labelled as ‘low fat’ often contain additional sugar which affects sleep.

In general it is best to try and prepare meals from scratch – that way you will know exactly what they contain.

The main sleep stoppers are caffeine, alcohol and sugar. These need to be regulated during the day and restricted during the hours before bedtime. The body needs a sufficient amount of ‘fuel’ to get through the night, so a balance needs to be found that will help you make it through the night without hunger.

Food for Thought

Anxiety is one of the main causes of insomnia. Worrying over what you eat will not help you sleep. Weight loss and body image dominate the media affecting how we feel about ourselves and making us preoccupied with what we eat. Worrying over food will keep you awake and add to all the other stresses that affect sleep.

Finding a balance and cutting down on the ‘sleep stoppers’ makes sense. Worrying over every mouthful will only make it harder to sleep. Try to cut out the alcohol and restrict the coffee for a few nights each week and see how well you sleep – it might become a lifetime habit!