We all know what a lack of sleep feels like and aside from tiredness it affects our attention, concentration, creativity, learning, memory, decision-making and emotional reactions that can impact on day-to-day life.
The effect of diet on sleep is not clear cut but what you choose to eat and drink across the day may play a role in sleep as does the timing of meals before you go to bed. These five golden rules below can help you to plan your diet to promote a good night’s sleep.
1. Limit the foods that can prevent you from falling asleep
Spicy foods
If you’re prone to heartburn or indigestion then spicy foods are only going to exacerbate the condition, leaving you uncomfortable in bed. No matter how much you enjoy these foods you need to be realistic if they’re getting in the way of a good night’s sleep.
Foods containing tyramine
We’ve all heard the old wife’s tale about cheese and nightmares. The truth in this is up for debate, but a certain amino acid found in cheese may affect our ability to sleep. Along with other foods such bacon, ham, aubergines, pepperoni, avocado, nuts, soy sauce and red wine, cheese contains the amino acid called tyramine. This amino acid has been shown to inhibit sleep by encouraging the release of a hormone called norepinephrine, which stimulates the brain, increases heart rate, releases glucose and increases blood flow to the muscles.
Sugar
Food and Nutrition surveys have shown that adults eat twice the recommended amount of 6 teaspoons per day, most of which comes from soft drinks, table sugar (added to foods and drinks), confectionary, puddings and desserts.
Sugar can reduce the activity of orexin cells, which stimulate parts of the brain that produce dopamine and norepinephrine; two hormones that keep us aroused and physically mobile. Researchers at Cambridge University have found that orexin cells are sensitive to blood glucose levels, which means if your indulging in lots of sugar then their activity is reduced, leaving you sleepy and more prone to napping that may disrupt sleep later during the night.
2. Choose to eat foods that heal
Foods containing tryptophan
This amino acid is needed to make a hormone called melatonin, which regulates our sleep-wake cycle.
Tryptophan exists in smaller amounts than other amino acids in the body, which it has to compete with to cross the barrier through to the brain. Carbohydrate foods stimulate the release of insulin that balances blood sugar and also promotes the clearance of these other amino acids from the bloodstream, allowing tryptophan to cross through to the brain more easily. Include plenty of tryptophan-rich foods in your diet such as meat, poultry, tofu, dairy foods and bananas and include carbohydrate-rich foods such as pasta, rice and potatoes as part of your evening meal.
Foods containing vitamin B6, magnesium and calcium
These three nutrients are involved in the production of melatonin in the body. Magnesium also activates the parasympathetic nervous system by binding with gamma-aminobutyric (GABA) receptors responsible for quieting down nerve activity, encouraging relaxation. Research published in the European Neurology Journal found that disturbances in sleep were related to low levels of calcium.
Vitamin B6 is found in many foods such as fish, poultry, wholegrain cereals, eggs and vegetables. Whilst most of us get enough in our diet, vitamin B6 is easily depleted with stress or excessive alcohol intake. Magnesium-rich foods include nuts, seeds, beans, pulses, brown rice and quinoa, and those rich in calcium include dairy food, tofu, dark green leafy vegetables, beans, pulses and dried fruit.
3. Watch what you drink
It’s common sense that drinking too much before you go to bed can cause you to wake up to use the bathroom so try and limit your fluid intake a couple of hours beforehand. What you choose to drink before bed and during the day can also have an effect on sleep.
Alcohol
Alcohol is common way of relaxing in the evening before bed, but the effects can go either way when it comes to sleep. The effects of alcohol can include dehydration, increased need to visit the bathroom during the night or heartburn that can all fragment sleep. Alcohol also interferes with the flow of calcium into nerve cells of the brain that control sleep. Try cutting down on the booze and drinking with your evening meal can help lessen the effects.
Foods containing caffeine
Caffeine is a stimulant that blocks the chemicals in the brain that make you sleepy and is found in coffee, tea, soft drinks and chocolate. Not everyone is sensitive to caffeine and a gene called CYP1A2 is responsible for controlling the enzyme that determines how fast you metabolise it. If you have the fast variant of the gene, then you metabolise caffeine four times quicker than those with the slow variant.
As caffeine can remain in the body for 3-5 hours (12 hours in some people), avoiding it from midday is a good strategy if you have difficulty getting to sleep. Try refreshing, energising, caffeine-free alternatives such as ginger and lemon in hot water or Rooibos tea.
4. Time your meals with your bedtime
Eating directly before you go to bed is never a good idea and whilst this may not directly impact on your sleep, the effects of heartburn or indigestion may do so. You can lessen the risk of heartburn or indigestion by eating smaller meals throughout the day and at least a couple of hours before bed. Choose low fat meals (quicker to digest) with a good balance of starchy carbohydrates and proteins; these help to stimulate bile production in the gall bladder that aids digestion. Take your time to eat as this stimulates digestive enzymes and avoid food and drinks such as citrus fruits, coffee, tea, chocolate, mint and fizzy drinks that can trigger heartburn.
5. Consider supplements
Magnesium
The National Diet and Nutrition Survey has shown that 13% of adults don’t get enough magnesium in their diet. It’s also been shown that we absorb only 50% of the magnesium from the food in our diet. The demand for this mineral is also increased from stress and low levels have been shown to upset sleep as well as impacting on tiredness and fatigue.
Magnesium is involved in the regulation of melatonin and a study published in the Journal of Review of Medical Sciences showed how taking a magnesium supplement helped to improve levels of melatonin, sleep time and sleep efficiency (reduction in waking up during the night).
Try a magnesium supplement such as Healthspan Opti Magnesium (£5.99 for 30 tablets) or magnesium salts in your bath a couple of hours before bed.
5-HTP
5-hydroxytryptophan (5-HTP) is a unique amino acid and involved in the production of melatonin.
Supplementing with 5-HTP may improve sleep architecture by extending the amount of time spent in REM sleep, helping you to wake up feeling more refreshed. Research has shown how 5-HTP may be particularly useful for sleep disturbances associated with fibromyalgia (condition that characterised by muscle and bone pain as well as general weakness) by reducing pain perception.
Start with 100mg of 5-HTP every night, building up to a maximum of 300mg and use for three months then stop for a month so you can establish the impact of this supplement. Try Healthspan Night Time 5-HTP (£16.99 for 60 tablets).
A lack of sleep can be debilitating in the short term and more damaging over a longer period of time. Trying to re-establish your sleep pattern can be a challenge and involves many factors that equate to good sleep hygiene. Diet is just one of the things that can influence sleep and understanding the effects can help you to develop a sleep ritual to get your sleep back on track.
About the Author / Rob Hobson
Rob Hobson is a consultant nutritionist working with wellbeing supplement brand Healthspan. Rob also works with private clients and can be found at www.robhobson.co.uk
