Exposure to ultraviolet (UV) rays is the leading cause of premature aging, and one of the main concerns for skin cancer.

Chemical and mineral, or physical, are the two general types of sunscreens available. They can be differentiated by their SPF (sun protection factor) agents, which have their own mechanism for protection. Chemicals absorb into the skin and work by absorbing or scattering UV rays, while minerals sit on top and actually reflect UV rays off of the skin.

Chemical is a funny word. All matter is made of chemicals, including humans and organic ingredients. When I talk about chemicals in this post, i'm referring to the synthetic chemicals that make up most of our sunscreens.

Choosing Broad-Spectrum:

Most of us buy sunscreen products based on its SPF number. The higher, the better! Not exactly.

The SPF of a product only indicates protection against UVB rays, while disregarding UVA rays. This is very bad, as we get way more UVA exposure than UVB. A product can state it's broad-spectrum, but it still might not be effective at protecting against both UVA and UVB radiation.

There is a rating system for UVA protection in sunscreen, called the PA rating. It has three different rankings which are listed as: PA+, PA++, PA+++. The more plus symbols indicates higher UVA protection.

The Difference Between UVA and UVB Rays:

UVA rays aren't blocked by the ozone layer or clouds, and therefore make up the majority of UV radiation reaching Earth's surface. They penetrate more deeply into the skin than UVB rays and cause photo-aging, which leads to wrinkling, leathering and other signs of sun damage.

UVB rays are mostly absorbed by the ozone layer, and have different strengths because they can be reduced by clouds blocking the sun. UVB rays only account for a small portion of the UV spectrum. They penetrate the epidermis, the first layer of skin, and cause sunburns.

Sunscreens should even be used during winter months because the ozone layer thins out and absorbs less of the sun's UV radiation. Especially if you're snowboarding or skiing, as snow and ice on the ground reflect UV rays.

Both UVA and UVB rays can lead to skin cancer, whether malignant or benign.

Chemical

• Absorb into the skin, and eventually the bloodstream 
• Must wait 20-30 minutes before it becomes effective 
• May start to breakdown during sunlight exposure

The truth is that chemical sunscreens are toxic. Some of the most common chemical sunscreen ingredients include: oxybenzone, avobenzone, octisalate, octocrylene, octinoxate, and homosalate. Chemical sunscreen products usually contain two to six of the above listed ingredients (but there are others as well). All of these ingredients can have negative implications on our health.

Oxybenzone, for example, is the most common ingredient used in sunscreen products in America. Around 600 brands use it, such as Coppertone, Banana Boat, Hawaiian Tropic, and Neutrogena. The U.S. Center for Disease Control (CDC) released a study that revealed 97% of Americans have oxybenzone in their blood.

Oxybenzone has been shown to cause allergic reactions, and cell death. It's also a penetration enhancer, meaning it helps other potentially harmful chemicals in the same product penetrate the skin. So, instead of just oxybenzone finding its way into our blood, it brings other potentially harmful ingredients with it!

Oxybenzone and other sunscreen chemicals also have devastating affects on coral reefs, causing bleaching and die-offs.

Needless to say, chemical sunscreens are not healthy!

Mineral

• Does not absorb into skin, but rather sits on top 
• Acts as a mirror by reflecting UV rays off of the skin 
• Becomes effective immediately after application 

Now, onto mineral sunscreens. There are two ingredients that fall under this category: zinc oxide and titanium dioxide. They both work by reflecting UV rays off of the skin's surface. They don't absorb into your skin, or most importantly, your bloodstream.

Think back to when lifeguards used to have that white stuff on their nose, that's zinc oxide!! But don't worry, using it nowadays won't be as obvious.

Sun protection should be your top consideration when buying sunscreen. According to Skin Deep's Environmental Working Group (EWG), mineral sunscreens (in particular, zinc oxide) deliver the best UVA and UVB protection. 

It's best to use a mineral sunscreen with only zinc oxide, or a combination of both zinc oxide and titanium dioxide. While titanium dioxide is great at protecting against UVB rays, it does not protect against UVA rays as well as zinc oxide does. Also, zinc oxide is considered safer to use on the skin as it doesn't cause irritation. It's even used in rash creams for babies.

Comparison Of Chemical and Mineral Sunscreen Ingredients

Courtesy of the Environmental Protection Agency, this graph is a good comparison between the 17 FDA approved sunscreen agents, and their efficacy for protecting against UVA and UVB rays.

Reading a sunscreen label:

On a product's label, all sunscreen agents will be listed under "Active Ingredients". However, just because the sunscreen ingredients are safe and healthy, doesn't mean the rest of the ingredients in the product are! 

All of the other ingredients in a sunscreen product are listed under "Inactive Ingredients". If you can't pronounce most of what you're reading, it's probably not a healthy product. 

Completely avoid any product that contains fragrance or parfum, parabens, propylene glycol, or any type of PEG (PEG-50, for example).

I always recommend oil-based products that are certified organic because they don't require synthetic preservatives, emulsifiers, or any additional additives. They usually have the added benefit of naturally healing the skin after UV exposure and protecting it from free radicals, which causes premature aging.

Check out my recent post to become a savvy shopper for natural and organic products.

If mineral sunscreens are so healthy and effective, then why aren't all sunscreens made with minerals?

Well, money of course!

It's more expensive to use zinc oxide and titanium dioxide than it is to use chemicals. You need to use a lot more minerals in a formula to obtain broad-spectrum protection. They're also heavier and usually leave a white sheen on the skin.

Nanoparticle Minerals:

Because of the heaviness of mineral sunscreens, companies often market theirs as being "clear" when applied to skin. These are zinc oxide or titanium dioxide nanoparticles, which were manufactured to be microscopic. They can potentially cause damage to DNA within skin cells. Keep a look out for products that are "non-nano" (I'll list some good recommendations below).

Why Uncoated Minerals?

Nanoparticles are more susceptible to degradation, so they're often coated with an inert substance to prevent free-radical formation on the skin. However, the coatings themselves can break down and create additional free-radicals.

Therefore, it's wise to use a mineral sunscreen that's non-nano and uncoated.

Steer Clear of Sunscreen Sprays And Powdered Makeup:

Spray sunscreens and powdered makeup with sunscreen agents in them should be avoided, whether they're chemical or mineral-based.

Inhalation and the impact on lungs is a concern, mainly from nanoparticles and chemical sunscreens. Also, sprays and powders are not an adequate substitute for the protection you get from creams and liquids. Sunscreen protection depends on how much you put on, and it's hard to tell whether or not you're putting on enough with sprays and powders.

Both Badger and Raw Elements sunscreens are broad-spectrum.

The Takeaway

It's extremely important to properly protect yourself from the sun when you're outside, even if it's winter. Be cautious about which sunscreen products you choose to use, as they could cause more harm than good.

A non-nano, uncoated zinc oxide sunscreen that contains mostly certified organic ingredients is the best choice for protecting skin.