The authors of a new systematic review1 published in the National Library of Medicine sought to take a closer look at the relationship between the Mediterranean diet and melatonin production.

While you might recognize melatonin as a popular sleep supplement, it’s actually a hormone the body makes on its own with the help of environmental cues like darkness. When you have a peak in melatonin, it makes it easier to fall asleep.

Our bodies’ natural melatonin levels should fall in the morning and rise at night, but with the introduction of artificial light and a decrease in time spent outdoors, our melatonin-producing signals have gotten all out of whack.

The researchers noted that while a lot has been published about the effect of supplemental melatonin on sleep, the specific melatonin-related effects of diets and certain foods have not been looked at as closely.

They found that some of the staples of the Mediterranean diet—tomato, nuts, and olive oil—can all contain high levels of melatonin depending on how they are produced.

There is a chance this makes the diet more supportive of sleep, though more research needs to be done in this area.

Scientists agree that while supplemental melatonin can be helpful in supporting sleep every once in a while (like when adapting to a new time zone), it may not be safe to take on a regular basis. This is because it could disrupt your body’s natural melatonin production, lead to dependence, or disrupt your overall hormonal balance.

Instead, they recommend talking to your doctor and implementing lifestyle changes, like light exposure and diet, before turning to over-the-counter sleep aids.

Improving your sleep hygiene requires several steps, but eating more delicious foods, and melatonin-rich ingredients is likely low-hanging fruit.