(NaturalNews) A team from Warwick Medical School in the U.K. has found that people who maintain healthy vitamin D levels are 43 percent less likely to get heart disease or diabetes. After evaluating 28 different studies conducted on nearly 100,000 people, researchers concluded that people who eat oily fish two or three times a week and five servings of fruits and vegetables a day are able to achieve healthy levels of vitamin D.While the team evaluated only natural sources of vitamin D, including from sunlight exposure and consumption of oily fish like tuna, salmon, and mackerel, it is probable that supplementation with natural vitamin D3 would prove to have the same effect.Published in the journal, the study revealed that high levels of vitamin D reduce the risk of developing cardiovascular disease by 33 percent, metabolic syndrome by 51 percent, and type-2 diabetes by an astounding 55 percent.According to Dr. Johanna Parker, one of the study authors, sunlight exposure is the best way to get vitamin D. "People should expose themselves for 30 minutes twice a week  this means exposing the face and arms with no sunscreen. This would provide the body with adequate vitamin D," she explained.Some experts recommend getting sunlight exposure every single day, especially in the summer when the sun delivers the most ultraviolet (UV) rays which produce vitamin D in the skin. Twenty minutes of sunlight exposure on a summer day can produce a healthy 20,000 IU of vitamin D in the skin, delivering optimal protection from all kinds of diseases.Last summer, a study published inalso found that vitamin D helps to prevent diabetes and can even help those who already have the disease. "Vitamin D has widespread benefits for our health and certain chronic diseases in particular," said Sue Penckofer, Ph.D., R.N., and co-author of that study.It appears that people who have diabetes are generally low in vitamin D, which is also the case with many other diseases. Since vitamin D-deficiency and serious illness are so closely related, many medical professionals are advising people to have their levels checked to be sure they fall within a healthy range. More often than not, people who are acutely ill are deficient in the necessary vitamin.If one is deficient in the vitamin, it is best to get more sunlight exposure, eat foods with vitamin D, and supplement with vitamin D3 in order to achieve optimal levels.Sources for this story include: