You have likely heard the directive to wear sunscreen daily. Sunscreen prevents burns and DNA damage from ultraviolet light exposure. It also “lowers your risk of developing squamous cell carcinoma by about 40%, and your melanoma risk by 50%”, according to Dr Hadley King, a New York-based dermatologist.
Sunscreen use has aesthetic benefits too, like preventing wrinkles and age spots; researchers have found that those who wear sunscreen daily, regardless of the weather or how much time they spend outside, have more youthful skin than those who only apply sunscreen on sunny days.
While all sunscreen provides some amount of UV protection (broad-spectrum products provide the most) only two active sunscreen ingredients have been classified as safe and effective by the Food and Drug Agency in the US: zinc oxide and titanium dioxide.
Should this affect your choice of sunscreen? Here’s what you need to know about sunscreen ingredients and safety.
Why has the FDA only approved two sunscreen ingredients?
In the US, sunscreens are regulated as over-the-counter drugs, which are subject to rigorous safety requirements and animal testing, as well as a notoriously slow-moving approval process.
In 2019, the FDA announced a sunscreen reassessment proposal, asking companies to thoroughly test the chemicals in their products and submit their data for safety assessment. However, for companies, retesting formulas can be time-consuming and come with the risk of rejection, negative publicity and expensive reformulations. So far, their participation in the reassessment has been minimal, leading to what the Environmental Working Group describes as a kind of “regulatory limbo”.
Emily Spilman from the EWG notes that there haven’t been enough studies for the FDA to ascertain the safety level of about a dozen active chemical ingredients currently used in US sunscreen, including avobenzone, dioxybenzone and homosalate. This doesn’t mean the chemicals are necessarily unsafe, but that their effects when absorbed through the skin and into the bloodstream require further study.
Until companies thoroughly vet their own products, essentially holding themselves accountable to the FDA’s request for more safety data, lesser-studied sunscreen chemicals will remain in the US market, Spilman explains.
What harmful sunscreen ingredients do we need to avoid?
While there isn’t sufficient data to establish the safety of some chemical ingredients, several are endocrine disruptors, meaning they may affect the body’s production of hormones like estrogen, androgen and progesterone at certain exposure levels, based on evidence from in vitro, animal and some human studies.
“Some recent studies have shown that some chemical sunscreen ingredients may be potentially harmful – particularly oxybenzone, octinoxate, and homosalate – because they mimic hormones,” explains King.
Of these ingredients, there is the most evidence against using oxybenzone, which has been linked to reproductive issues and allergic reactions.
A late-2000s report from the CDC found that oxybenzone is in the bodies of nearly all Americans, “and levels are highest in those that use sunscreen”, notes Spilman, though the study did not assess health effects.
Oxybenzone and octinoxate are also considered to have harmful effects on coral reefs and other marine species. Hawaii became the first US state to ban sunscreens containing these chemicals in 2018.
What are the safest sunscreen ingredients?
The potential harms of not wearing any sunscreen outweigh the potential risks posed by chemicals in sunscreen. Excessive sun exposure can damage the DNA in our skin cells; over time, that damage can build up and cause cells to grow excessively, causing skin cancer. Skin cancer is the most common form of cancer in America, with two people dying from the disease every hour. In short, nobody’s saying skip the sunscreen.
However, those seeking the safest products in the US market should look for physical, also known as “mineral,” sunscreens with zinc oxide and titanium dioxide. That’s because “there are fewer concerns about absorption and safety”, says King. Also, “physical sunscreens are less likely to clog pores and irritate complexions, particularly for those with sensitive skin”, she notes, as opposed to chemical sunscreens, which have smaller molecular structures and are more readily absorbed by the skin.
While aerosolized mineral sunscreen particles can be harmful when inhaled in large amounts, either acutely or via chronic, low-dose exposure, researchers from Penn State University found that using mineral spray sunscreens as directed is safe.
Physical sunscreens meet higher safety standards, but not everyone likes them, for valid reasons. “For darker skin types, it can be difficult to find physical sunscreens that don’t leave a white cast,” says King, and some mineral formulas also have a reputation for sitting on top of the skin in an uncomfortable, greasy layer.
If you can’t find a mineral sunscreen you like, King says “chemical ingredients can be reasonable alternatives” – just avoid those containing oxybenzone and octinoxate. A general piece of wisdom on sunscreen is that the best one is the one you actually use.
Are sunscreens from outside the US superior?
Plenty of commentators have suggested that there are better sunscreens in other countries.
Regulatory bodies in Europe, Asia and Australia have approved a much wider range of UV filter ingredients for use in sunscreens compared with the FDA in the US, allowing for more creative, modern sunscreens with chemicals like bemotrizinol, one of the safest and most vetted chemicals on the global market.
Currently, Swiss sunscreen company DSM-Firmenich is working to secure FDA approval for bemotrizinol. Sources report that this has already taken the company 20 years and cost $18m despite congressional attempts to speed up the application process for new UV filters.
Outside the US, sunscreens are regulated as functional cosmetics. California-based dermatologist Dr Annie Chiu has described Korea’s sunscreen regulation process, for example, as involving “less bureaucracy”.
“It does not mean Korean sunscreens are less safe,” she notes. “Generally, most sunscreen ingredients, even chemical ones, are safe and have been on the market for years.” In fact, their ingredients often have larger molecular sizes – meaning they don’t absorb as readily into the bloodstream.
Meanwhile, in Australia, sunscreens are closely regulated by the nation’s Therapeutic Goods Association, which regularly tests sunscreens to ensure ingredients remain at safe levels. The government further mandates companies selling sunscreens in Australia maintain records demonstrating the safety and efficacy of their products.
Other countries’ more efficient approaches to sunscreen regulation underscore the US system’s dysfunction. The representative Alexandria Ocasio-Cortez spoke out on the issue in a social media post last August: “It is so clear how advanced the rest of the world is on sunscreens – and we deserve better here in the US.”
