Zinc Oxide May Be in Your Favorite Mineral Sunscreen, But Is It Safe and Effective?

Zinc oxide is the main ingredient in mineral sunscreens. It is a fine, white powder that is either synthetic or derived from the mineral zincite. Zinc oxide helps form a physical barrier on your skin to reflect and absorb the sun’s UVA and UVB rays. It is also used in other skincare products to help protect and soothe irritated skin.

Zinc oxide can be a great ingredient to protect your skin from irritation and the sun. However, there are some claims that zinc oxide nanoparticles can enter the bloodstream through your skin and accumulate in your organs. So, is zinc oxide as effective and safe as some people think?

Here’s what to know about its risks and benefits.

Zinc oxide is considered safe when used in mineral sunscreen and skin care products like calamine lotion, ointments, and diaper creams. It’s one of two sunscreen ingredients the U.S. Food and Drug Administration (FDA) categorizes as GRASE (generally recognized as safe and effective).

However, many mineral sunscreens have tiny zinc oxide nanoparticles that help reduce the white cast it can leave on your skin and smooth its coarse texture. Some people think that these particles can enter your bloodstream and that high concentrations of zinc oxide build-up in your organs could lead to potentially carcinogenic effects, DNA damage, and inflammation linked to cancer and infertility. But is there any truth to those claims?

Most research has found that zinc oxide sunscreen has low concentrations of zinc oxide nanoparticles, which can’t significantly penetrate the skin or enter the bloodstream. Researchers have also found that zinc oxide nanoparticles barely penetrate the epidermis, the top layer of the skin, which would make it difficult to reach the bloodstream.

Zinc oxide is primarily known as an ingredient in mineral sunscreens, but it can also protect your skin in other ways. 

Sun Protection

Zinc oxide creates a physical barrier over your skin that absorbs and reflects a broad spectrum of UVA and UVB rays that can burn and damage it. Regularly using sun protection containing zinc oxide reduces your risk of sunburn and sun exposure, which can lead to skin cancer and premature aging. 

Exposure to UV rays increases your risk of skin cancers like melanoma, basal cell carcinoma, and squamous cell carcinoma. 

Wound Protection and Healing

Zinc oxide is often an active ingredient in calamine lotion, hemorrhoid creams, ointments, and diaper rash creams. Its ability to create a protective layer on the skin helps prevent friction and soothe irritated skin in conditions like eczema, minor burns, diaper rashes, and hemorrhoids. It also helps speed up and promote healing.

Zinc oxide helps stop oozing from skin that is irritated by poison ivy, poison sumac, and poison oak.

Zinc oxide sunscreen or skincare products are typically safe for most people. However, there are some considerations:

  • Some people may be allergic to zinc oxide. You may experience swelling, itching, and rashes.
  • It can be drying and may irritate already dry skin. If you’re new to zinc oxide, always do a patch test before slathering it over your skin.
  • It usually leaves a white cast on your skin. People with darker skin tones may also find that zinc oxide sunscreens leave a white or gray cast on their skin, making it difficult to blend in. A white cast is less likely with nanoparticle zinc oxide sunscreens or tinted sunscreens.
  • It’s not suitable for newborns and babies under six months. While babies are prone to sunburn, their delicate skin makes them more likely to experience skin irritation and rashes from sunscreen. Instead, keep young babies out of the sun with shade, hats, and lightweight clothing.

Titanium dioxide is another ingredient found in mineral-based sunscreens. Sometimes it is used alone or in combination with zinc oxide for sun protection. Like zinc oxide, titanium dioxide coats the skin to create a barrier that absorbs and reflects UV rays to prevent deeper skin penetration and sun damage. The FDA also categorizes titanium dioxide as generally recognized as safe and effective (GRASE).

The main difference is that titanium dioxide is only effective at protecting the skin from UVB and short-wave UVA rays. Zinc oxide can effectively block the entire spectrum of UVA and UVB rays, offering broad-spectrum protection needed to help prevent sun damage.

Zinc oxide is also less likely to penetrate the skin compared to titanium oxide.

To use zinc oxide creams safely and effectively, follow these tips:

  • Always apply to clean, dry skin.
  • Wash your hands before application.
  • When using zinc oxide creams to protect or dry irritated skin, gently apply a thin layer to cover the affected area and avoid rubbing.
  • If you’re applying zinc oxide sunscreen, apply roughly a shot glass-sized amount to cover the skin. Remember to apply it 15 minutes before sun exposure and reapply every two hours. If you’re swimming or sweating, you’ll need to reapply more frequently.
  • Store zinc oxide products in a cool, dry place that isn’t directly in the sun.

Zinc oxide is considered a safe and effective mineral sunscreen ingredient. It is also a good way to protect irritated skin from diaper rash, poison ivy, and burns.

While there is some concern about zinc oxide nanoparticles, research has found they can’t significantly penetrate the skin and enter your bloodstream to cause negative health effects.

Leave a Reply

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

Back To Top