If you used to drink warm milk before bedtime as a child, or if you noticed the “sleepy girl mocktail” trend on social media last year, you know how endlessly appealing it can be to find the perfect food or drink to help you sleep.
But research in this field is just emerging, experts say — and there is no magic bullet ingredient or food that will guarantee a flawless slumber.
What is clear, though, is that what you eat throughout the day, and your diet in general, both play important roles in how you sleep. Here’s what we know.
What might help?
Some research has found links between consuming certain foods and drinks and better sleep, said Marie-Pierre St-Onge, an associate professor of nutritional medicine at Columbia University and the co-author of the new book, “Eat Better, Sleep Better.”
In several small trials, for example, researchers found that adults who drank two servings of tart cherry juice per day — one in the morning and another in the evening — slept longer and woke less throughout the night compared with when they consumed placebos.
Studies have also found benefits from consuming other foods, such as about nine ounces of raw beefsteak tomatoes two hours before bedtime, two kiwi fruits one hour before bedtime, and one-third of a cup of walnuts throughout the day.
But many of these studies were funded by industry groups, so their findings could have been biased. And they had various limitations. Most were performed on small groups of people with specific characteristics, for instance, such as 15 elite athletes, eight older adults with insomnia or 36 postmenopausal women with obesity. So researchers may not find the same results on larger or more diverse groups.
Some trials also weren’t placebo-controlled, so we can’t say if their results stemmed from the foods themselves or from participants’ expectations that their sleep might improve, said Michael Grandner, director of the sleep and health research program at the University of Arizona.
That said, it theoretically makes sense why some foods might help, Dr. Grandner said. Tart cherries, tomatoes, kiwi and walnuts contain the hormone melatonin, which could help signal to the brain that it’s time to sleep, he said. Other melatonin-rich foods — like rice, oats, cranberries, sunflower seeds, almonds, pistachios and some mushrooms — may help too, but researchers haven’t looked into whether they have similar effects, Dr. St-Onge said.
Your brain also uses tryptophan, an essential amino acid you can only get from food, to make melatonin, Dr. St-Onge said. Tryptophan is notoriously abundant in turkey, but other sources like chicken, fish, cheese, sunflower seeds, tofu and white beans provide similar amounts. There is little research into whether consuming tryptophan-rich foods might improve sleep, Dr. St-Onge said, but small studies that have tested supplements or cereals containing the amino acid have suggested that there could be benefits.
Rather than focus on any one food or nutrient as the key to good sleep, however, it may be better to think about your diet as a whole, Dr. St-Onge said. When researchers scrutinize the eating and sleeping habits of people around the world, they notice that those who regularly consume more fruits and vegetables, complex carbohydrates like fiber, and healthy fats (from sources like salmon, olive oil and nuts) tend to sleep better than those who consume less of those foods and nutrients.
They’ve also found links between following a Mediterranean-style diet and lower risks of insomnia symptoms, like trouble falling asleep or waking during the night, said Arman Arab, a research fellow at Brigham and Women’s Hospital in Boston who led a recent meta-analysis on the topic.
Diets that prioritize fruits, vegetables, whole grains and other plant foods are rich in antioxidants and other compounds that tamp down inflammation, which has been associated with sleep disturbances, said Erica C. Jansen, a nutritional epidemiologist at the University of Michigan School of Public Health. They also contain folate, vitamin B6, zinc and magnesium, which your body needs to produce melatonin from tryptophan, Dr. St-Onge said.
But the studies that have found associations between certain diets and better sleep can’t prove cause and effect — they can only show correlations, Dr. Arab said.
People who tend to eat more healthfully, for example, may also exercise more or eat earlier in the day or at more consistent times — all of which are better for sleep, Dr. Jansen said.
What might hurt?
Research suggests that people who tend to eat less healthfully — consuming many ultraprocessed foods, refined carbohydrates or added sugars, for example — are at greater risk for insomnia symptoms, Dr. St-Onge said. One small study she published in 2016 found an association between consuming more saturated fats and sugars during the day and poorer sleep quality.
Scientists don’t fully understand why this may be, she said; it could be that these foods cause sleep-disrupting inflammation, or that when people eat them, they eat less of the foods that help with sleep.
And when people are short on sleep, they tend to crave — and eat — these less healthy options. That can create “this cycle of poor sleep leading to poor diet quality, which we think then feeds back onto poor sleep,” Dr. Jansen said.
Close to bedtime, it’s best to avoid spicy or high-fat foods, which may disrupt your sleep by causing heartburn, Dr. Grandner said. And salty foods may cause you to drink more fluids, prompting more nighttime trips to the bathroom, Dr. St-Onge said.
You may also want to watch your caffeine consumption, Dr. St-Onge said. The ability to process caffeine tends to decrease with age, so if you’re having trouble sleeping, she said, consider consuming most of your caffeine earlier in the day, such as before 2 p.m.
The post What to Eat and Drink for a Good Night’s Sleep appeared first on New York Times.
