What you eat affects how you sleep. Some foods contribute to restful sleep; other foods keep you awake.
Sleepers are tryptophan-containing foods. Tryptophan (which is converted to an amino acid called L-tryptophan) is the raw material that the brain uses to build sleep-inducing substances (relaxing neurotransmitters) serotonin and melatonin.
Adequate serotonin levels promote deep, restorative sleep. Eating carbohydrates with tryptophan-containing foods makes this calming amino acid more available to the brain. A high carbohydrate meal stimulates the release of insulin, which helps clear those amino acids that compete with tryptophan from the bloodstream, allowing more of this natural sleep-inducing amino acid to enter the brain and manufacture sleep-inducing substances.
Eating a high-protein meal without accompanying carbohydrates may keep you awake, since protein-rich foods also contain the amino acid, tyrosine, which perks up the brain.
Foods that are high in carbohydrates and calcium, and medium-to-low in protein are ideal for promoting sleep:
An all-carbohydrate snack, especially one high in junk sugars, is less likely to help you sleep. You’ll miss out on the sleep-inducing effects of tryptophan, and you may set off the roller-coaster effect of plummeting blood sugar followed by the release of stress hormones that will keep you awake.
The best bedtime snack is one that has both complex carbohydrates and protein, and some calcium. Calcium helps the brain use the tryptophan to manufacture melatonin. This explains why dairy products, which contain both tryptophan and calcium, are one of the top sleep-inducing foods.
Some components of food, such as caffeine, artificially wake us up, so it makes no sense to have stimulant-containing foods before bed. Unfortunately, this applies not only to coffee, but to all caffeine-containing foods, and to theophylline-containing foods (like black tea) as well.
Chocolate and many soft drinks (including diet soft drinks) have substantial amounts of caffeine. An ounce of chocolate can contain 10-60 mg of caffeine, and a soft drink will usually fall into this same range. Brewed coffee can have over 100 mg per cup, depending on the grind and brewing time.
Eliminating these foods from your evening meal routine is recommended for improved sleep.