Melatonin is a hormone produced in the body by the pineal gland and also produced in the gastrointestinal tract. This hormone plays a key role in synchronizing circadian rhythms and helps regulate the sleep-wake cycle in mammals. In addition to this function, melatonin is a potent antioxidant that protects the body from free-radical damage. Although synthetic melatonin has gained popularity in recent times as a nutritional supplement, melatonin can be found in a variety of foods.
Common foods such as olive oil, wine and even beer are rich sources of the hormone. Melatonin is also found in many common fruits and vegetables including tomatoes, grape skins, tart cherries and walnuts. While most of these foods contain significantly smaller amounts of melatonin than the dose typically found in a supplement, incorporating a variety of these foods into the diet is easy and could supply beneficial amounts of the compound.
An important consideration is whether the body can obtain sufficient amounts of melatonin from food alone. A recent comprehensive review in the Journal of Pineal Research cites studies that show significant increases in both melatonin levels and antioxidant status in the blood of people who consumed melatonin-rich foods.
Melatonin acts as an antioxidant by directly scavenging damaging agents that promote inflammation and aging and can cause conditions including cancer and cardiovascular and neurological problems. Although more research is needed, there is consensus about the potency of the compound in this respect: Regardless of a specific, curative effect, melatonin consumed through food can provide healthy levels of antioxidants.
Melatonin from a food source is typically used for its health benefits and not as a sleep aid. This is primarily due to the quantity, spread and time at which melatonin is consumed through food. If melatonin use is primarily for regulating sleep patterns or to alleviate the symptoms of jet-lag, then an over-the-counter supplement may be a better choice. Always consult your doctor before using supplements, because they could interact with other medicines.
In addition to evaluating the amount of melatonin directly from the food source, consider how altering the food might affect melatonin availability and absorption. For example, cooking at high temperatures or fermentation might affect how much melatonin can be obtained from the food. Ideally, the food consumed should be fresh and unprocessed to obtain the maximum nutrient value.