Despite the fact that our bodies make vitamin D in response to sunlight, a large percentage of the population is deficient in it. Having insufficient vitamin D levels has been linked to a number of poor health outcomes, like some cancers, weak bones, and mental health issues. Now a new study published in the European Heart Journal shows that vitamin D deficiency can increase the risk of cardiovascular disease. Getting more sunlight, and eating foods like dairy products, orange juice, and soy products, can increase vitamin D levels. Supplements can be a good strategy for some people as well.