Skin Cancer And The Need For Sunscreen Awareness

5 min readApr 7, 2022

While everyone requires sun exposure to synthesise vitamin D, unprotected exposure can cause skin damage and premature skin ageing (photoaging), resulting in skin that appears dry, thinner, and wrinkled. Repeated damage can cause skin cancer.

According to the World Health Organisation (WHO), two to three million non-melanoma skin cancers and one to two million melanoma skin cancers are diagnosed each year worldwide. The Skin Cancer Foundation estimates that in the United States, more than two people lose their lives to skin cancer every hour.

Bob Marley, a musician, was diagnosed with melanoma, which took his life at the age of 36.

UV-A and UV-B rays are proven risk factors for skin cancer. Let us know more about UV rays.

UV-A rays: These rays are associated with skin burning and their intensity is constant during daylight hours throughout the year.
UV-B rays: These rays are associated with skin cancer, and their intensity varies.

What can you do to protect yourself from UV rays?

The most effective way to protect yourself from UV rays is to limit your exposure. The American Academy of Dermatology recommends:

Apply a broad-spectrum sunscreen with a minimum SPF of 30 generously to all exposed skin.
Protect yourself by wearing long-sleeved shirts, long pants, a wide-brimmed hat, and sunglasses. Choose sunglasses that provide UV protection.
When possible, seek shade. Remember that UV rays are strongest between 10 a.m. and 4 p.m.
Take extra care when near water, snow, or sand. These surfaces reflect UV rays, increasing your chances of getting sunburned.
Lip balm with a minimum SPF of 15 should be used to protect your lips.
Get vitamin D from a healthy diet that may include vitamin supplements.

Sunscreen is a vital component of the UV ray protection strategy. Let’s take a look at the 5 W’s (& H) of sunscreen.

The 5 W’s (& H)

Why should you use sunscreen?

Sunscreen protects you from UV rays and lowers your risk of skin cancer. Daily use of a sunscreen with an SPF of 15 reduces the risk of squamous cell carcinoma by 40% and melanoma by 50%.

Who should use sunscreen?

All people over the age of six months should use sunscreen.

When should you apply sunscreen?

You should apply sunscreen every day, 30 minutes before going outside. Reapply every two hours of exposure and immediately following swimming or excessive sweating. You should apply sunscreen even on a cloudy day, as UV rays can get through to the ground.

Where should you apply sunscreen?

Experts recommend that you should apply sunscreen to your entire body before dressing for the day, or at least to every exposed area of your body.

How much sunscreen should you use?

You should use one ounce (roughly the size of a shot glass) for your entire body.

What type of sunscreen should you use?

Choose a sunscreen with “broad-spectrum” protection. Broad-spectrum sunscreen provides protection against both UV-A and UV-B rays.

Choose a sunscreen with an SPF of 30 or higher.

Explaining The Sunscreen

There are two types of sunscreen:

Physical Sunscreen: This sunscreen acts like a shield, sitting on the surface of the skin and deflecting UV rays. They contain active ingredients: zinc oxide and/or titanium oxide.
Chemical Sunscreen: This sunscreen acts like a sponge, absorbing the UV rays. They contain active ingredients: avobenzone, homosalate, octinoxate, octisalate, octocrylene, and oxybenzone.

The EWG’s sunscreen database rates physical sunscreen better than chemical sunscreen.

The Food and Drug Administration (FDA) only proposes zinc oxide and titanium oxide as “generally recognised as safe and effective” (GRASE).

In January 2020, the FDA reported on the results of an extended clinical study showing that six chemical sunscreen ingredients (avobenzone, homosalate, octinoxate, octisalate, octocrylene, and oxybenzone) enter the bloodstream even after a single application and can remain in the body for extended periods of time.

Misconceptions About Sunscreen

Sunscreen Is Waterproof: No!

No sunscreen is waterproof or sweat-proof. “Water-resistant” does not mean “waterproof”. If a sunscreen claims to be water-resistant, it must specify whether it lasts for 40 or 80 minutes while swimming or sweating. When drying off with a towel, sunscreen usually rubs off, necessitating the application of additional layers.

Sunscreen Use Lower Vitamin D Levels: No!

Sunscreen works by filtering out UV-B rays. In theory, sunscreen use lowers vitamin D levels, but since very few people apply enough sunscreen to block all UV-B rays or apply sunscreen irregularly, hence sunscreen effect on vitamin D might not be that important. An often cited Australian study found no difference in vitamin D levels between adults randomly assigned to use sunscreen one summer and those assigned a placebo cream.

Tanning Prevent Skin Cancer: No!

Tanning doesn’t prevent skin cancer. Tanning is the skin’s response to injury from UV rays. When UV rays reach the skin, the skin makes more melanin. This is the first line of defence against UV rays. A sunburn occurs when the amount of UV damage exceeds the amount of protection provided by the skin’s melanin.

Higher SPF Give Significantly More Protection: No!

Higher SPFs do provide more protection, but the difference becomes increasingly small as the number increases.

A sunscreen with an SPF of 15 blocks out 93% of UV-B rays.
A sunscreen with an SPF of 30 blocks out 97% of UV-B rays.
A sunscreen with an SPF of 50 blocks out 98% of UV-B rays.
A sunscreen with an SPF of 100 blocks out 99% of UV-B rays.

Both low and high SPF sunscreen protect you for the same amount of time regardless of their SPF.

Dark-Skinned People Do Not Need Sunscreen: No!

While people with darker skin are more protected against UV rays, but they still need a broad-spectrum sunscreen. UV-A rays are not blocked by melanin and can lead to premature skin ageing. Dark-skinned people are also at risk of skin cancer.