Melatonin levels, which generally increase in the dark at night, appear to fight obesity by stimulating the production of "beige fat" — a type of fat cell that, unlike "white fat" tends to burn calories instead of storing them. As a result the beige "good fat" helps regulate body weight and metabolism.
 

Beige fat is naturally produced by the body, but is also found in fruit and vegetables like mustard, Goji berries, almonds, sunflower seeds, cardamom, fennel, coriander, and cherries.
 

The new study, published in the Journal of Pineal Research, was conducted on laboratory rats by an international team of scientists — from the University of Granada Institute for Neuroscience, the Hospital Carlos III, Madrid, and the University of Texas Health Science Center in San Antonio. The researchers said the findings may explain why melatonin has been shown to have metabolic benefits in treating diabetes and hyperlipidemia.
 

The take-home message of the research: Sleeping in the dark and consuming foods with melatonin could help control weight gain and prevent cardiovascular diseases associated with obesity and diabetes.