Dark-skinned people need up to six times as much sunlight as those with fair skin to produce the same levels of Vitamin D, says a new study .
Researchers at the Australian National University found that fair-skinned people need over four minutes in the summer sunshine to produce enough Vitamin D whereas dark-skinned people need more, reported online edition of Daily Mail.
Acceptable levels of sunbathing also depends on geography and the amount of solar ultraviolet radiation, says the study.
But people living in Britain would need twice the exposure because the sun's rays are not as intense.
Vitamin D is a steroid hormone that has long been known for its important role in regulating body levels of calcium and phosphorus, and in mineralization of bone.
Sunlight is the most abundant natural source that helps our bodies make vitamin D. About 10 percent of Vitamin D comes from food, such as oily fish.
Lack of sunlight can lead to Vitamin D deficiency, which can cause rickets in children, osteoporosis in adults, and also contribute to cancer, diabetes and hypertension, the study said. Scientists have also said excess exposure could cause harm.