The Dangers of Commercial Sunscreens

Wherever I go this summer, it seems that people are slathering or spraying sunscreen onto themselves and their children. Whether or not you want to use sunscreen, you essentially have no choice – aerosol sprays disperse and pollute the air, and sunscreens and sun blocks wash off in pools or lakes, contaminating the water. (Despite what labels proclaim, there is no such thing as “waterproof sunscreen.”)

I’m always surprised that people who would never consider consuming pesticides or toxins in their foods give no thought to applying powerful chemical substances to their bodies. Many people assume that whatever they apply to their skin stays on the surface. This is not the case. Our skin (which happens to be our largest organ) is remarkably adept at absorbing substances; thus many of the chemicals in skin care products penetrate into the skin, and end up in the bloodstream where they circulate throughout the body.

There are numerous problems associated with chemical sunscreens, including:

• Endocrine Disruption. Many of the most commonly used UV filters (including benzophenone-3, octyl methoxycinnamate, 4 methylbenzylidene camphor (4-MBC), octyl-dimethyl-PABA, and oxtinoxate) interfere with endogenous hormone production and activity. These chemicals are potent endocrine disrupters—which means they interfere with normal hormone function (especially estrogen, progesterone, testosterone, and thyroid hormones). Endocrine disrupters can cause reproductive problems (including early puberty, abnormal development of the male reproductive system, low sperm count, and infertility) and cancer (particularly reproductive cancers). These chemicals present an even greater danger to children, who have lower levels of endogenous hormones and because of their smaller size, are at increased risk of exposure to toxins.

• Free Radical Damage. Many of the chemicals in sunscreens have been found to generate free radicals, which cause cell damage (including damage to DNA). Free radicals trigger inflammation, which is the primary cause of skin aging and skin cancers.

• Photogenotoxic Effects. I find it ironic that when sunscreens are exposed to sunlight, even more harmful chemicals are created. Many of the chemicals in sunscreens become toxic when exposed to light, resulting in allergic reactions, chemical sensitivity, skin irritation, pigment changes, burning, and most disturbing of all, photogenotoxic (sunlight or ultraviolet induced DNA altering) effects.

• Increased Absorption of Toxins. Both the active ingredients and the base materials (such as alcohols, emulsifiers, lanolin, mineral oil, and petrolatum) in sunscreens can act as penetration enhancers, increasing the movement of other chemicals through the skin and into the bloodstream. For example, the application of insect repellents and sunscreen (a common summertime duo) can carry pesticides and other toxins into the bloodstream.

• Additional Toxic Ingredients. Other common ingredients, such as preservatives and artificial fragrances, add to the toxic load of sunscreens.

The campaign to use sunscreen has been aggressively publicized for decades; as a result, our use of chemical sunscreens has dramatically increased in the past 50 years. Dermatologists, primary care providers, and estheticians are among the professionals who strongly recommend sunscreen as a primary means for reducing the risk of skin cancer. Of the three primary types of skin cancer, cutaneous malignant melanoma (CMM) is the most dangerous. But despite the widespread availability and push to use sunscreen, the incidence of CMM in the U.S. continues to increase by 3% per year. Obviously, sunscreen isn’t providing the protection against CMM that we’re counting on (Planta MB, 2011).

The truth, in fact, is just the opposite. Studies show that sunscreens can actually increase your risk of skin cancer. This is because although most sunscreen agents are pretty good at preventing sunburns, they aren’t very good at blocking the UVA light that causes skin cancer. Unfortunately, what sunscreens effectively block are UVB rays, which are actually beneficial in moderation.

With all of the negative press regarding sun exposure, many people believe they’re doing the right thing by completely avoiding the sun. But the truth is that we need regular doses of sunshine to stay healthy. Not only is exposing our skin to the sun the only way that our bodies have to naturally create vitamin D (which is essential for bone, cardiovascular, and immune health); daily exposure to sunshine regulates melatonin production, improves sleep, and helps to fight depression.

This does not mean that we should go out and get as much sun as we want – we must exercise caution. At the beginning of the season, start gradually, limiting your exposure to perhaps as little as 10 minutes a day. Progressively increase your time in the sun by perhaps 5 minutes every week so that in a few weeks, you will be able to spend an hour or more in the sun (depending on your skin type) with minimal risk of skin damage.

The key is to never get burned. But don’t rely on sunscreen to protect you! Sunscreen should never be your first line of defense in shielding your skin from the sun. Far more effective is to cover up with sun protective clothing (long sleeved shirts and pants); broad brimmed hats; and sunglasses. In addition, a simple and effective solution is to seek out shade, particularly during the hottest part of the day.

As an herbalist, I recommend topical botanicals for both pre-and-post sun exposure. Scientists are discovering that certain herbs and spices contain potent compounds that protect against cancer, chronic disease, and reduce the effects of aging. Some of my favorite botanicals include green tea and turmeric, both of which have powerful anti-inflammatory properties and help to fight free-radical damage. In my post next week, I’ll talk more about the botanicals that I recommend and what I consider to be safe sunscreen ingredients. I’ll also address what I believe is a significant cause of skin aging and skin cancer—and it’s not the sun.