When you have enough Vitamin D in your bloodstream, research shows fat cells slow their efforts to make and store fat. But when your D is low, levels of parathyroid hormone (PTH) and a second hormone, calcitrol, rise, and that's bad. High levels of these hormones turn your body into a fat miser, encouraging it to hoard fat instead of burning it.
In fact, a Norwegian study found that elevated PTH levels increased a man's risk of becoming overweight by 40 percent.
Vitamin D can help you lose lard all over, but it's particularly helpful for the pounds above your belt. Studies at the University of Minnesota and Laval University found that D triggers weight loss primarily in the belly. One explanation: the nutrient may work with calcium to reduce production of cortisol.
The recommended daily intake is 800 ius with an upper limit of 2,000 ius.
Sources of Vitamin D: Sunlight, supplements, fortified milk, cod liver oil, salmon, tuna, mackerel