It’s no secret that a healthy diet affects so many different facets of daily life, and sleep is no exception. It’s recommended that adults get seven or more hours of sleep per night. Yet, according to the Centers for Disease Control (CDC), one out of three American adults get less than that. Since not getting enough sleep is linked with many chronic diseases and conditions, such as type 2 diabetes, cardiovascular disease, obesity and depression, focusing on strategies to promote better sleep can lead to better health. While a variety of strategies including exercise, a consistent sleep routine and limiting electronic devices around bedtime can support quality sleep –considering changes to what you eat and drink are other important variables.
Before we dive into the effects of diet on sleep, let’s first discuss the biology of sleep. Sleep is controlled by a variety of hormones in the body, specifically melatonin and serotonin. Melatonin helps regulate sleep and wake cycles, while serotonin signals the body to make more melatonin. Tryptophan, an amino acid found in a variety of protein-rich foods, is a precursor to melatonin and serotonin, which is why tryptophan-rich foods are often recommended for better sleep.
Tryptophan for Sleep
Studies have also shown that low tryptophan levels in the diet can impair sleep. Some tryptophan-rich foods include meat, seeds, nuts, cheese, eggs and soy products. Interestingly, there’s not a wide range of tryptophan content among meats; Turkey, chicken and beef have about 300 milligrams of tryptophan per 3-ounce serving. However, ounce for ounce, pumpkin seeds pack the highest tryptophan punch, with about 60% more tryptophan than turkey, chicken or beef. Fruits like cherries and kiwis also contain these sleep-promoting hormones and amino acid. Clinical trials have shown that cherry and kiwi consumption improve sleep quality and duration.
B Vitamins for Sleep
Sleep hormones are also regulated by micronutrients such as B vitamins. vitamin B12 is involved in melatonin secretion and is naturally found in animal products like meat, fish, milk, cheese and eggs. Some foods like breakfast cereals and alternative milks like soy, almond, coconut and rice are fortified with vitamin B12. Another important B vitamin for sleep is vitamin B6 because of its key role in the serotonin production. If you are looking to increase your B6 intake, turn to organ meats, potatoes and other starchy vegetables, or non-citrus fruit and fortified cereals.
When to Eat for Sleep
In addition to what should be included in the diet, there are a couple of things to limit or avoid. For example, the timing of meals can influence sleep. Studies have shown that eating large meals before bedtime can cause indigestion, acid reflux and heartburn which can disrupt sleep. As a result, the CDC suggests avoiding large meals before bedtime to allow for digestion. The National Sleep Foundation offers a more specific recommendation to finish meals two to three hours before bedtime.
Caffeine and Sleep
Caffeine can also impact sleep. For optimal sleep, avoid consuming caffeine a few hours before going to bed and keep your daily caffeine intake to less than 400 milligrams. 400 milligrams of caffeine amounts to about four cups of coffee, six ounces of espresso, eight cups of black tea or 13 cups of green tea. If you’re unsure how much caffeine is in common foods or beverages, check out this caffeine calculator.
Adequate sleep is essential for health, and one way to support quality sleep is to set up healthy eating habits that you can maintain over a long period of time. The 2020-2025 Dietary Guidelines for Americans emphasize the importance of building healthy and flexible patterns of eating. So, whether you choose to follow a vegetarian diet, Mediterranean-eating style or something in between, the most important things for you can do for good sleep and overall health are to eat a varied diet full of fruits and vegetables, whole grains, unsweetened, fat-free and low-fat varieties of dairy and fortified soy alternative foods and beverages, lean protein and healthy fats.
This article was written by Megan Meyer, PhD, and includes contributions by Kris Sollid, RD.