New research suggests that people with low levels of vitamin D may have an elevated risk for heart disease and stroke. And those with high blood pressure and vitamin D deficiency are at an even greater risk.
Researchers followed 1,739 people, average age 59, for 5 years and used blood samples to determine the level of vitamin D in their blood. They found that individuals with low levels of vitamin D had a 60 percent higher risk for heart disease, such as heart attack or stroke. They also found that those with high blood pressure and vitamin D deficiency had double the risk.
This research follows another recent study which suggests that people with higher levels of vitamin D have a better chance of surviving certain cancers.
Unfortunately there aren’t many foods that are rich in vitamin D. Fatty fish such as salmon has some. And milk is usually fortified with it. But mostly the body makes vitamin D when it’s exposed to sunlight.
Obviously, vitamin D deficiency is going to be more common in the northern hemisphere, during the winter months, when there’s not much sun. But there are plenty of people who never get out into the sun even when it is available.
So if you fall into either of these two categories, be sure to supplement your diet with Cod Liver Oil 
And if you happen to live where there’s plenty of sunshine available, experts say exposure to 10 to 15 minutes of sun three times a week is all you need to produce enough vitamin D to stay healthy.