Eating the right foods in the evening may help you get a better night's sleep. One of the foods sometimes recommended for people who have trouble sleeping is walnuts. While walnuts aren't a treatment for insomnia -- and it's not yet known whether they significantly improve sleep -- these tasty little nuts offer small amounts of potentially sleep-promoting nutrients.
A study published in "Nutrition Research and Practice" in June 2011 found that people who ate foods containing more of certain nutrients, including vitamin B-12, folic acid and thiamine, were less likely to have insomnia. Each ounce of walnuts provides 7 percent of the daily value for folic acid and 6 percent of the DV for thiamine. While this isn't a large amount of these nutrients, it will help get you closer to meeting the recommended intake for the day.
Getting more essential omega-3 fats in your diet may help you sleep a bit longer and wake up fewer times during the night, according to a study published in the "Journal of Sleep Research" in August 2014. Each ounce of walnuts provides 2.5 grams of the recommended 1.3 to 2.7 grams per day of the omega-3 fat ALA. The study used the omega-3 fat DHA, however, so it isn't clear whether walnuts will have the same effect. ALA can be converted to DHA in the body, but the conversion isn't very efficient.
Melatonin and Sleep
Some people take melatonin to help regulate their sleep-wake cycles and their body clock, allowing them to sleep better. Walnuts are a natural source of melatonin, potentially increasing your blood levels of this sleep-promoting substance. However, it isn't clear how many walnuts you'd need to eat to get enough melatonin to have an effect on your sleep.
Tryptophan and Sleep
Walnuts are one of the nuts highest in tryptophan, along with cashews. Tryptophan is perhaps best known as the ingredient in turkey often blamed for making people sleepy after their Thanksgiving meal. It may help you become more relaxed and ready to fall asleep by increasing the amount of serotonin in your body, and it may also help keep you asleep for longer during the night.