There is a lot of talk about diet and how it affects our sleep. Are there, after all, foods that help us sleep better or that make it difficult to sleep? What are these; What else affects our sleep? Let's look at the data and whether it is scientifically supported.

Meal timing

The first dietary factor that affects our sleep is the timing of our meals, meaning the time we eat and the amount of the meal. For example, if we eat dinner too early or avoid it, we might not be able to sleep since our stomachs will be rumbling. On the other hand, if we eat a large amount or too late or choose indigestible foods, we will also find it difficult to sleep because of stomachache or heartburn. A systematic review found that eating within three hours before bedtime is associated with increased reflux. Such conditions not only increase the time it will take us to fall asleep but will probably lead to waking up at night and, in general, restless sleep. Thus, it is good to adjust the time we eat and the quantities we consume at meals so that the dinner will better serve our sleeping. That depends on our daily activity schedule and our working hours.

Circadian rhythm

The circadian rhythm is the "clock" inside our body: the body receives stimuli from the environment on a twenty-four-hour basis and carries out biological processes. One stimulant is light, and the lack of it, that stimulates the secretion of specific hormones. You may have heard that exposure to screens at night inhibits melatonin production, so we do not get a good sleep. The timing of meals also affects the circadian rhythm similarly. Eating at unusual times, when we have a night shift, or if we travel in different time zones disrupts our internal clock. On the other hand, lack of sleep also disturbs the hormones ghrelin and leptin, making us hungry and not feeling full.

Food and dreams

Some people believe if they eat certain foods near bedtime, they will see specific dreams. The truth is that such a thing is not scientifically proven. A small study found a possible link between certain foods, especially dairy, and strange or disturbing dreams. However, many factors could affect them, such as eating slowly or in large quantities, alcohol, emotional food that we are likely to eat at night while in a strange emotional state, intolerances, etc.

Foods containing tryptophan

Tryptophan is an amino acid associated with good sleep because it is necessary for serotonin and melatonin creation. Tryptophan exists in foods with enough protein, such as meat, fish, legumes, dairy, etc. Fish also contains vitamin D and the omega-3 fatty acids that help. When we combine these foods with carbohydrates (bread, potatoes, rice, cereals, etc.), tryptophan's bioavailability increases; in other words, tryptophan does its job better.

Drinks and beverages with caffeine

A substance that significantly affects our sleep is caffeine. Coffee, tea, energy drinks, chocolate, and other products like fat burners contain caffeine. Drinking caffeinated beverages too close to bedtime is associated with delayed sleep and reduced sleep quality, especially for people who are intolerant to caffeine, so it is good to control the consumption of such beverages. On the other hand, hot decaffeinated drinks such as chamomile, warm milk, low-caffeine green tea, and passiflora tea may lead to better sleep.

Foods containing melatonin

Melatonin is the hormone that causes us to sleep. Although some foods contain enough melatonin, such as tart cherry juice and almonds, there is limited research on its effectiveness in this form.

Glycemic Index

The glycemic index measures how quickly carbohydrate-containing food raises blood glucose levels. Some evidence suggests that eating foods with a higher glycemic index (meaning they raise blood glucose more quickly), especially white rice, helps improve sleep and leads to falling asleep faster.

Foods containing magnesium

Magnesium activates the parasympathetic nervous system, leading us into rest, relaxation, and digestion mode. At the same time, it affects melatonin levels. Some studies report that magnesium supplements may improve sleep quality, but more research is needed. Foods that contain magnesium are seeds, oats, nuts, spinach, beans, whole grains, bananas, avocados, and soybeans.

Kiwi

A small 2014 one-month-long study found that eating two kiwis an hour before bed led to 42% faster sleep onset and improved sleep duration and quality. That may be related to the antioxidant or serotonin content of kiwifruit. Of course, we should examine this possible association by doing more research.

The diet quality

Some studies link the general diet quality with good sleep. For example, the Mediterranean eating pattern seems to lead to better sleep. On the other hand, a study showed that people who sleep for shorter periods are less likely to follow a diet that meets the average nutritional requirements of adults, which is a balanced and complete diet.

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