“Wear sunscreen. If I could offer you only one tip for the future, sunscreen would be it.”1 With these lines, Mary Schmich, Chicago Tribune columnist, made sunscreen famous overnight in her 1997 column on advice for youth. Science also endorses this tip and, for a long time, sunscreen has been touted as the miracle cream that protects the skin from cancer and other effects of overexposure to UV rays. But now it looks like the sunscreen may be causing a few burns of its own, especially among men.
What Goes Into Sunscreen?
While a dark tan may look good, the sun’s UV rays have been linked to skin cancer and scientists have long advised the need to either cover up or splash on some protective cream.2 UV radiation is of three types – UVA, UVB, and UVC. UVA rays can penetrate the skin up to 1 mm without burning the surface layers but can cause skin cancer and wrinkling. It can also damage cell membranes and the immune system. UVB is linked to the red burn visible on the skin after being in the sun for a long time. These rays can also cause skin cancer and damage the cornea, while UVC is harmless. Sunscreen is meant to offer protection against UVA and UVB.
Sunscreens are usually of two kinds – one goes into the outer layer of skin to absorb the UV rays, while the other coats the skin and acts as a physical barrier to UV rays. Both come with a sun protection factor (SPF), which indicates the level of protection from sunburn.
UV Filters And Fertility
Just as there are two types of sunscreen, there are two kinds of UV filters. The physical filters (made of insoluble mineral particles like zinc and titanium dioxide) block or reflect the UV rays. The chemical filters (with active ingredients such as avobenzone, homosalate, and oxybenzone) absorb the UV rays. Most sunscreens in the market contain chemical filters – and that’s where the connection crops us. Several commonly used UV filters seem to have a significant effect on male fertility, especially the motility of sperms.
As one study showed, the exposure to sunscreen ingredients that penetrate into the skin can cause sperm damage and feminization of the male reproductive system.3
What’s Causing The Damage?
Damage is being done in two ways. First, the chemical UV filters are letting compounds like oxybenzone creep into the skin. Oxybenzone is a hormone disrupter that acts like estrogen and can lead to DNA level damage of sperms.4
The second culprit is phthalates. Phthalates are a set of chemicals found in a variety of daily use products ranging from detergents, shampoos, and soaps to lotions like sunscreen. The UV filters containing these chemicals again act as hormone disrupters, essentially aping the activity of the female hormone progesterone. The result is damage to the sperms. Moreover, unnatural levels of any hormone, especially the female hormone in males, are bound to leave a mark.5
A recent announcement by the scientific community corroborates these findings, with results showing that 45% of sunscreen ingredients have a negative effect on sperm cells.6 The UV filters were found to inhibit sperm motility, mimic the behavior of progesterone, and damage overall sperm quality.
While more clinical studies are conducted, you would be well advised to reduce usage – but without compromising safety in the sun. Sunscreens with zinc and titanium dioxide as key ingredients are safer options. UV filters with these components show very low toxicity and no hormone disruption.7 Also, fill up on fruits and vegetables to raise antioxidant levels and boost resistance to sunburn. Till research firms up, good nutrition and a moderate amount of time in the sun may be a safer bet for men hoping to be fathers!
|↑1||Schmich, Mary. “Advice, like youth, probably just wasted on the young.” Chicago Tribune 1 (1997): 1.|
|↑2||Armstrong, Bruce K., and Anne Kricker. “The epidemiology of UV induced skin cancer.” Journal of Photochemistry and Photobiology B: Biology 63, no. 1 (2001): 8-18.|
|↑3||Hauser, Russ, J. D. Meeker, N. P. Singh, M. J. Silva, L. Ryan, S. Duty, and A. M. Calafat. “DNA damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites.” Human reproduction 22, no. 3 (2007): 688-695.|
|↑4||Nakamura, Noriko, Amy Inselman, Gene White, Ching-Wei Chang, and Deborah Hansen. “Effect of Maternal and Lactational Exposure to Oxybenzone on Testes Development in Male Rats.” Biology of Reproduction 87, no. Suppl 1 (2012): 259-259.|
|↑5||Duty, Susan M., Narendra P. Singh, Manori J. Silva, Dana B. Barr, John W. Brock, Louise Ryan, Robert F. Herrick, David C. Christiani, and Russ Hauser. “The relationship between environmental exposures to phthalates and DNA damage in human sperm using the neutral comet assay.” Environmental Health Perspectives 111, no. 9 (2003): 1164.|
|↑6||Rehfeld, Anders, Dorte Louise Egeberg, Steen Dissing, and Niels Erik Skakkebaek. “FRI-121: Organic Ultraviolet Filters Mimic the Action of Progesterone on Human Sperm and Interfere with Sperm Functions.” (2016).|
|↑7||The Trouble with Oxybenzone and Other Sunscreen Chemicals, Environmental Working Group.|