Why is Sunscreen Bad? The Dark Side of SPF

Sunscreen has become a ubiquitous part of our daily routine, especially during outdoorsy summer days. While we all are aware of the dangers of sun exposure and UV rays, sunscreens come with a little-known dark side that most of us are unaware of. Sunscreens are marketed to protect the skin against ultraviolet (UV) radiation, which can cause skin cancer, aging, and sunburns. However, recent studies and research have uncovered that sunscreens may come with their own set of risks and negative effects. In this article, we will dive into the dark side of SPF, the potential risks, and what we can do to mitigate the damages.

Types of sunscreens: The Active Ingredients

Sunscreens mainly come in two varieties, mineral, and chemical. The active ingredients in mineral-based sunscreens are usually titanium dioxide and zinc oxide, while chemical-based sunscreens can contain several different active ingredients, such as oxybenzone, octinoxate, avobenzone, and homosalate.

Mineral Sunscreens

Mineral sunscreens, also known as physical or natural sunscreens, typically contain zinc oxide, titanium dioxide or a mixture of both. They work by sitting on top of the skin and physically blocking or reflecting UVA and UVB rays. Unlike chemical sunscreens, mineral sunscreens are less irritating and less likely to cause skin allergies. They are also safer for the environment, as mineral sunscreens are not toxic to marine life or coral reefs.

Chemical Sunscreens

Chemical sunscreens use chemicals to create a chemical reaction that absorbs UV radiation before it penetrates the skin. The most common active ingredients in chemical sunscreens are oxybenzone, octinoxate, avobenzone, and homosalate, among others. Chemical sunscreens are generally thinner and easier to apply, but they come with a few negative effects.

Negative Effects of Sunscreen

Sunscreen and Hormones

Several of the active ingredients used in chemical sunscreens, such as oxybenzone, have hormonal effects. Oxybenzone can penetrate the skin, enter the bloodstream, and mimic hormones, disrupting normal hormonal functioning. Studies on rats have shown that oxybenzone has fertility and reproductive system implications, affecting hormones and sperm.

Sunscreen and Skin Allergies

Chemical sunscreens contain several ingredients that are harmful to the skin, causing irritations and allergic reactions. Oxybenzone, in particular, has been linked to skin allergies and reactions, such as atopic dermatitis or eczema. Other active ingredients, such as avobenzone, can also cause allergies and skin irritations.

Sunscreen and Coral Reefs

Chemical sunscreens wash off swimmers and eventually end up in the ocean. Several studies have shown that some active ingredients in chemical sunscreens such as oxybenzone, octinoxate, and homosalate are toxic to coral reefs and other marine organisms. A single drop of oxybenzone in the ocean is enough to cause damage to coral reef larvae, causing coral bleaching and death.

Sunscreen and Vitamin D Deficiency

Vitamin D is an essential nutrient for human health, and most of it is produced by the body when the skin absorbs sunlight. However, sunscreen use can decrease the production of vitamin D in the body. Vitamin D deficiency is linked with several health issues such as osteoporosis, cardiovascular disease, and some forms of cancer. Despite the negative impact, the amount of vitamin D the body gets from sun exposure is significantly higher than what most people think, and vitamin D is regularly found in many dietary supplements, making the importance of avoiding sun damage greater than replacing the vitamin D the body is making.

What Can We Do to Mitigate the Risks?

Physical Protection

The best way to protect against the sun’s harmful rays is by physical protection, rather than chemical. This means avoiding direct sunlight by staying in the shade, using hats or visors or protective clothing. When swimming, wearing a rash guard can provide an extra layer of protection.

Mineral-based Sunscreens

Mineral-based sunscreens avoid the problematic active ingredients in chemical sunscreens. They also form a physical barrier on the skin, providing a little more protection than chemical sunscreens. However, mineral sunscreens are harder to apply and can leave a white, chalky residue on the skin.

Choose Your Sunscreen Wisely

If you’re going to use a sunscreen, choose a safer and more natural product like mineral sunscreen. Look for products that don’t contain oxybenzone or octinoxate, although a few of these ingredients may not be a problem, look closely at the ingredients list before making your purchase. Checking the SPF rating is important as well, as SPFs above 30 don’t provide much more protection than SPFs below 30.

Frequently Asked Questions

Here are some commonly asked questions about sunscreen and its potential negative impacts:

  • Does sunscreen cause skin cancer?
    No, sunscreen doesn’t cause skin cancer. Skin cancer is caused by UV radiation from the sun or from tanning beds, which sunscreen is meant to protect against.
  • Can sunscreen cause sunburn?
    No, sunscreen helps to prevent sunburn. However, sunscreens not specifically designed for sun burn can be misleading and any sunscreen, chemical or mineral has its own likelihoods of causing skin irritations or allergic reactions.
  • What is the difference between mineral and chemical sunscreens?
    Mineral sunscreens use the minerals titanium dioxide or zinc oxide to physically block or reflect UV rays, while chemical sunscreens use chemicals like oxybenzone to absorb UV radiation. Mineral Sunscreens are usually perceived as better options than chemical sunscreens.
  • What is reef-safe sunscreen?
    Reef-safe sunscreen typically contains only mineral sunscreens and avoids oxybenzone and octinoxate, which harm marine life and coral reefs. Just like mineral sunscreens avoid select harmful active ingredients for more sustainability and adjustivity with sensitive skin types.

Sunscreens are an essential part of our daily lives during sunny days, providing the necessary protection against UV radiation. However, it is important to acknowledge that sunscreens also come with their own set of risks and negative effects. While mineral-based sunscreens may provide a safer alternative, physical avoidance methods can provide even more protection, making hats, long-sleeved clothing, and physical barriers just as important in protecting your health.


  • Environmental working group. (2021). What’s wrong with high SPF? [http://www.ewg.org/sunscreen/report/whats-wrong-with-high-spf/](http://www.ewg.org/sunscreen/report/whats-wrong-with-high-spf/)
  • Mineral Sunscreen. (2021). All about Mineral Sunscreen. [http://www.mineralsunscreen.com/](http://www.mineralsunscreen.com/)
  • NOAA. (2021). A to Z of Coral Bleaching: Coral Bleaching: A Disease of Coral Reefs. [http://oceanservice.noaa.gov/education/kits/corals/coral02_zooxanthellae.html](http://oceanservice.noaa.gov/education/kits/corals/coral02_zooxanthellae.html)
  • The Conversation. (2021). How much of your vitamin D do you get from the sun? Capital Health Network. [http://www.chnact.org.au/news/how-much-your-vitamin-d-do-you-get-sun](http://www.chnact.org.au/news/how-much-your-vitamin-d-do-you-get-sun)

Leave a Reply

Your email address will not be published. Required fields are marked *