Sleep deprivation is associated with a host of chronic conditions, such as type 2 diabetes and heart disease. Finding ways to improve your ability to get to sleep is therefore vital to a long and healthy life. The causes of sleep loss can be surprising and one that may raise a few eyebrows is refined carbohydrates.
Refined carbs are essentially carbs that have been stripped of their goodness through processing.
They are commonly found in added sugars, white bread, white rice, and fizzy drinks.
A study published The American Journal of Clinical Nutrition, found that postmenopausal women who consumed a diet high in refined carbohydrates – particularly added sugars – were more likely to develop insomnia.
What’s more, women whose diet included higher amounts of vegetables, fibre, and whole fruit (not juice) were less likely to develop problems with insomnia.
READ MORE: Best supplements for sleep: Taking melatonin before bed could help you fall asleep better
Different kinds and amounts of carbohydrates increase blood sugar levels to varying degrees.
The study’s researchers suggest this effect may help to explain the association.
“When blood sugar is raised quickly, your body reacts by releasing insulin, and the resulting drop in blood sugar can lead to the release of hormones such as adrenaline and cortisol, which can interfere with sleep,” Gangwisch said.
The researchers suggested that the rapid spikes and troughs in blood sugar after eating refined carbs may trigger insomnia.
They found that the higher the dietary glycemic index – particularly when fuelled by the consumption of added sugars and processed grains – the greater the risk of developing insomnia.
The glycaemic index (GI) is a rating system for foods containing carbohydrates. It shows how quickly each food affects your blood sugar (glucose) level when that food is eaten on its own.
They also discovered that women who consumed more vegetables and whole fruits (not juices) were less likely to develop insomnia.
“Whole fruits contain sugar, but the fibre in them slow the rate of absorption to help prevent spikes in blood sugar,” said Gangwisch.
“This suggests that the dietary culprit triggering the women’s insomnia was the highly processed foods that contain larger amounts of refined sugars that aren’t found naturally in food.”
General tips to promote sleep
Winding down is a critical stage in preparing for bed and there are simple ways to relax.
The NHS recommends trying the following:
- A warm bath (not hot) will help your body reach a temperature that’s ideal for rest
- writing “to do” lists for the next day can organise your thoughts and clear your mind of any distractions
- Relaxation exercises, such as light yoga stretches, help to relax the muscles. Do not exercise vigorously, as it will have the opposite effect
- relaxation CDs work by using a carefully narrated script, gentle hypnotic music and sound effects to relax you
- Reading a book or listening to the radio relaxes the mind by distracting it
- there are a number of apps designed to help with sleep.
Avoid using smartphones, tablets or other electronic devices for an hour or so before you go to bed as the light from the screen on these devices may have a negative effect on sleep.
“You should also contact your GP if you have insomnia that lasts for more than four weeks,” adds the NHS.