While sunscreen is known to block the sun's ultraviolet radiation from penetrating the skin, Dr Arthur W. Perry, MD, FACS, who is also a member of the Medical Advisory Board for The Dr. Oz Show, is of the opinion that chemical sunscreens can cause low sperm counts and infertility apart from contributing to the development of breast and ovarian cancers in women. He recommends using a micronised zinc oxide containing SPF 15 broad-spectrum sunscreen instead.

Sunscreens, which have always been known to protect the skin from the harmful rays of the sun and prevent sunburn, premature ageing and even reducing the risk of skin cancer, can also have negative effects on the body. According to Dr Arthur W Perry, who is a board certified plastic surgeon, an adjunct associate professor at Columbia University, and a member of the Medical Advisory Board for The Dr Oz Show, applying chemical sunscreen on the body can lead to low sperm counts and even infertility. Sunscreens, as per Dr Perry, can also cause early puberty and premature breast development among girls.

According to Dr Arthur W Perry, endocrine disruptors, found in chemical sunscreen function like estrogen. They are capable of contributing to the development of breast and ovarian cancers in women. Other endocrine disruptors may increase the chance of prostate cancer in men. However, Dr Perry added that there is no evidence to prove that they cause cancer.

Dr Perry argues that unlike physical sunscreen or sunscreen with zinc oxide and titanium dioxide, chemical sunscreens get absorbed in the skin and quickly travel their way to the bloodstream. "They scatter all over the body without being detoxified by the liver and can be detected in blood, urine, and breast milk for up to two days after a single application. That would be just fine if they were uniformly safe - but they're not," says Dr Perry.

Dr Perry, who had mentioned about the ill effects of chemical sunscreen before on The Dr Oz Show, also said that out of the 17 individual sunscreen ingredients that are approved by the FDA, 15 are chemicals that absorb UV light, two are minerals that reflect UV light. "Of these 15, nine are known endocrine disruptors. To be effective, chemical sunscreens need to be rubbed into their skin 20 minutes before sun exposure. They do a pretty good job at blocking UV light, but they actually get used up as the sun shines on them. In fact, some sunscreens lose as much as 90% of their effectiveness in just an hour, so they need to be reapplied often. This is not the case with zinc oxide and titanium dioxide, the two mineral, or physical, sunscreens. These two work very differently - they sit on the surface of the skin and physically block UV light," the well-known plastic surgeon added.