A study of 93,676 women aged 50 to 79 years has shown that eating foods with a low glycemic index positively affects the quality of sleep. (1)
In particular, foods rich in fiber in the daily diet reduced the risk of sleep disorders such as insomnia by 13-14%. While refined carbohydrates such as sugar can cause alcohol-like drowsiness immediately after eating, in the long term, they increase the time it takes to fall asleep by up to 16%.
The quantity and quality of carbohydrates affect sleep.
An obstacle to previous research on the effects of food on sleep quality was not prolonging the studies for a considerable period. For example, previous studies suggested that a small serving of high-GI carbohydrates was associated with falling asleep faster.
However, observation for several months (and even years) significantly changes the picture. The behavior from the time of the last meal and 1 to 4 hours before bedtime changes as meals are repeated.
Among the nutritional factors that affect sleep quality, studies note not only the glycemic index of foods but also their glycemic load (that is, the quality and quantity of carbohydrates consumed), as well as the balance of fats in the diet. Research has also helped identify that a lack of nutrients and an excess of processed foods are not suitable for sleep.
What do you need to eat at night to sleep better?
Statistical studies show that people who regularly adhere to the Mediterranean diet are less likely to suffer from insomnia. (1)
These diets are based on the use of many whole foods – different vegetables, unsweetened fruits, whole grains, seeds, and nuts, with an abundance of shellfish, fish, chicken, natural yogurts, and vegetable oils.
Here are some nighttime feeding tips to help you sleep better:
- Avoid saturated fat and eat more fiber
Another study, published in 2020, looked at the relationship between sleep quality and dietary supplementation. For four days, the subjects consumed foods specially prepared for them (with a specific composition and caloric content), and on the fifth day, they ate whatever they wanted.
It turned out that the abundance of saturated fat against the background of a lack of fiber foods reduces the duration of the deep sleep phase; it is during this period that the body restores reserves.
- Eat more protein
The lack of protein in the diet alters processes in the body related to such essential functions as sleeping and eating. Eating less protein than your body needs can affect melatonin production and increase the urge to eat.
- Drink cherry and kiwi juice
A study in Australia found that eating two kiwis an hour before bed for a month positively affects the rate of falling asleep on the depth and duration of sleep. However, this study did not involve a control group, meaning the placebo phenomenon could have worked. (2)
Scientists have also found a correlation between drinking cherry juice and improving sleep quality in people with insomnia. Apparently, due to the tryptophan content in cherries. (3)
Lack of sleep increases food cravings
Reducing nighttime sleep to 4-5 hours is associated with an increase in calories consumed per day and a choice in favor of junk food.
In the studies above, when sleep deprivation was only 2 hours per day, people felt more hungry, resulting in going for unhealthy snacks like sweets.
This is explained by an increase in the production of ghrelin (a hormone that controls hunger) and a decrease in the hormone GLP-1 (which contains the feeling of fullness). In simple terms, appetite increases while satiety from food decreases.
Although fast carbohydrates can cause drowsiness (which accelerates sleep), in the long term, adequate sleep requires eating foods with a low glycemic index. In addition, the proportion of monounsaturated fats in the diet affects the quality of sleep.
Scientists have observed a direct correlation between proper nutrition and the ability to sleep soundly. The poorer the diet, the worse the sleep, and the worse the quality of rest.