A South African sleep expert, Dr Kevin Rosman, often says “all the good stuff happens while we sleep”, and he’s right. The American Centre for Disease Control and Prevention (CDC) considers sleep insufficiency an important public health challenge, reporting an average of 50 to 70 million American adults diagnosed with sleep disorders.
Sleep specialists repeatedly warn that sustained sleep restriction is associated with metabolic changes that contribute to weight gain, mood disorders, stressful emotions and increased micronutrient requirements, such as vitamins (e.g. B vitamins, vitamin C) and minerals (e.g. magnesium, iron, calcium).
Sleep problems can also contribute to the development of a variety of conditions such as hypertension, heart disease, inflammation and diabetes. Sleep deprivation can alter circadian rhythms, which affects hormone levels, mood, immunity and digestive balance.
How can I improve my sleep quality?
Medical professionals have identified the following factors that influence sleep:
- Maintaining a consistent routine with a regular bedtime and wake up time
- Avoiding forced sleep
- Regular exercise
- Using your bed only for sleeping
- Avoiding alcohol, nicotine, or caffeine consumption before bedtime
- Eating a well-balanced diet with appropriate times for breakfast, lunch, dinner, and snacks to avoid hunger during the night
- Maintaining a dark and quiet environment in the bedroom
- Dealing with worries before bedtime
- Avoiding the use of all electronic devices in bed
How does what you eat affect your sleep patterns?
A balanced diet is very important as it provides a variety of nutrients that all have specific functions in maintaining a good sleep cycle. Lean proteins provide the body with an amino acid called tryptophan, which converts to a neurotransmitter called serotonin that assists in regulating sleep patterns. Regular mealtimes can also assist in stabilising daily energy levels to assist in forming healthy sleep routines.
Maintaining optimal blood glucose levels throughout the day is important for good quality sleep. This can be achieved through regular and structured eating patterns, as well as choosing high quality, wholegrain carbohydrates that are low GI, releasing sugars (glucose) slowly into the bloodstream. This prevents a rollercoaster of fluctuating blood glucose levels, affecting our energy levels during the day and consequently our sleep quality at night.
Does body weight affect sleep?
The incidence of the condition sleep apnoea is on the rise as it is directly related to obesity. Sleep apnoea is defined as recurring episodes of cessation of breathing during sleep, caused by blockage of the upper airway. Weight loss is one of the most important management strategies to reduce the incidence of sleep apnoea, along with limiting alcohol consumption and stopping smoking.
What foods should you concentrate on for better sleep and why?
It is important to note that there is no “magic bullet” when it comes to sleep nutrition. There is no one particular food that has been shown by research to significantly induce sleep or improve sleep.
As no single food can outweigh the effects of one’s overall diet, it is recommended that a high quality diet rich in wholegrains, fresh fruit and vegetables, lean proteins (legumes, fish, skinless chicken and low fat dairy) as well as healthy fats (mono- and polyunsaturated fats) should contribute to good sleep hygiene. On the other hand, the following foods have been studied and do show promise in their ability to enhance sleep quality or onset.
Chamomile tea has a soothing effect and reduces anxiety which can help to calm one down before bedtime.
Honey is claimed to have a mild sedative affect and can be stirred into chamomile tea or warm milk. Honey is high in sugar, though, and should be used sparingly with no more than ½ to 1 teaspoon added to tea.
Milk contains tryptophan, promoting serotonin production and thereby improving sleep. Make sure you choose low-fat milk as opposed to full-cream milk, which contains saturated fat.
Serotonin regulates sleep patterns, and foods that contain natural serotonin include bananas, avocado pears and tomatoes.
Cherries are one of the few natural foods that contain melatonin. This is a hormone that is released when it gets dark, and promotes optimal sleep.
Magnesium may assist with muscle relaxation and is found in wholegrain cereals, nuts, pulses and green, leafy vegetables.
What time should you eat dinner to ensure optimal sleep?
Try to eat approximately 2 to 3 hours before going to bed. Studies have shown that consuming small amounts of high quality carbohydrate such as wholegrains, pulses and fresh vegetables before bed can assist in the transportation of the amino acid tryptophan. Tryptophan is important for the production of serotonin, a neurotransmitter that plays an essential role in optimal sleep quality.
If you have problems with insomnia, avoid the following:
Caffeine and other stimulants should be avoided as they keep the brain buzzing, which is the last thing we want when we’re trying to fall asleep. Foods that contain caffeine include coffee, tea, cola drinks and chocolate.
Large quantities of food take longer to digest and may cause gastrointestinal disturbances that can interfere with sleep.
High fat foods
Foods that contain large amounts of fat may delay gastric emptying and cause discomfort, which can affect sleep.
Too many alcoholic drinks
Alcohol can keep us from entering deeper sleep cycles, thereby affecting our quality of sleep.
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2. Axelsson J, Rehman J-u, Akerstedt T, et al. (2013) Effects of Sustained Sleep Restriction on Mitogen-Stimulated Cytokines, Chemokines and T Helper 1/ T Helper 2 Balance in Humans. PLoS ONE 8(12): e82291.
3. Thoropy, M. J. (2011). History of sleep medicine. Sleep Disorders, 3-25.