Hiding away from sun rays to protect oneself from skin diseases can harm one's health in many other ways, says an expert. A study published in the British Medical Journal (BMJ) has revealed that applying sun screen can contribute to Vitamin D deficiency. Though it is vital to protect our skin from harmful radiations, experts fear some people are taking it too far, reports themirror.co.uk. According to the study led by professors Simon Pearce and Time Cheetham, people are getting far too little sun exposure, which the body needs to produce Vitamin D. Staying out of the sun altogether can cause bone problems, and in extreme cases rickets and osteoporosis, depression and even weight gain. However, the study does not suggest that one should not apply sun screens and let skin burn but to keep in mind that small doses of unprotected sun exposure are vital. According to experts, we need about 20 minutes of sunlight a day to help bodies produce enough vitamin D, known as the "sunshine vitamin".