How to Use Sun Protection to Prevent Skin Cancer | The Daily Dose

How to Use Sun Protection to Prevent Skin Cancer

July 30, 2020 9 min read

Woman sitting on a bridge in the sun

Ultraviolet radiation (UV) is the part of sunlight that we can neither see nor feel, and yet it damages our skin. Recent research has shown that sunlight can cause aging and skin damage. Therefore using sun protection, following best practices for sun exposure, and maintaining a healthy diet are key to reducing your risk. Some of the best supplements for reducing your risk of skin cancer include antioxidants, colorful plant compounds (carotenoids), and probiotics, as well as vitamin B-3 (nicotinamide) and collagen.

Few things can lift our mood and boost our mental health easier and faster than some time outdoors. The summer sun feels good on our skin, warming us and creating feelings of well-being. But that same sun exposure, carried on for too long, can cause painful sunburns that increase the risk of developing skin cancer.

All of that time inside means your skin may be sun-starved and paler than it would normally be at this time of year. Jumping back into outdoor activities can be a recipe for pain, peeling skin and unnecessary health risks unless you take the appropriate precautions.

Keeping your skin healthy and protected from the sun is important for reducing your risk of skin cancer. It will also keep you looking younger longer. Here’s what you need to know about sun protection, and how to enjoy your summer without the nasty side effects of burning:

Why is sun protection so important?

Sunlight, also known as solar radiation, is composed primarily of three wavelengths measured in nanometers (nm)(1):

  • Infrared light - wavelengths that are longer than 800 nm
  • Visible light - wavelengths between 400 and 800 nm
  • Ultraviolet light (UV) - wavelengths that are shorter than 400 nm

We can feel infrared light in the form of heat. We can see visible light with our eyes. But we can neither see nor feel UV light. And that is unfortunate because UV radiation is the component of sunlight that can damage our skin.

According to the World Health Organization, 90 percent of the UV radiation that reaches the ground isUVA radiation (315-400 nm), with only 10 percent beingUVBradiation (280-315 nm)(2). However, it is the UVB rays that are the most concerning.

Chart detailing the varying levels of UV rays

UVA affects the skin by (3):

  • Penetrating the skin
  • Activating existing skin pigments, causing the skin to darken quickly
  • Impacting connective tissue and blood vessels causing structural damage
  • Reducing skin elasticity when there is prolonged exposure, which leads to wrinkles and premature aging of the skin

UVB affects the skin by(3):

  • Penetrating the skin
  • Stimulating the production of new skin pigments, causing deep darkening of the skin that lasts a long time
  • Causing the upper layer of skin (the epidermis) to thicken
  • Causing sunburn, or inflammation of the skin, when there is prolonged exposure, which significantly increases the risk of skin cancer
Infographic showing how UVA and UVB sun rays penetrate the dermis

It is important to remember that small doses of UV radiation are important for your health and trigger your skin to produce vitamin D, which is a powerful immune system booster in your body(3). However, prolonged and repeated exposure to the sun causes damage to your skin, aging it prematurely and increasing your risk of skin cancer. Therefore it is important to learn the facts about sun protection and to use a combination of methods to reduce your long term health risks.


Does the sun really age your skin?

UV radiation penetrates the skin and damages skin structure. Both skin collagen and elastin are damaged by UV radiation. These two components provide skin with its firmness and elasticity(4).

The two main mechanisms of damage to the skin collagen matrix from UV exposure include reduced collagen generation and increased collagen destruction(5). This breakdown in skin structure leads to the signs of aging including wrinkles, blotchy discoloration, broken blood vessels and skin cancer(6).

In a study involving 298 caucasian women divided into sun-seeking and sun-avoiding behavior groups, 80 percent of the visual signs of facial aging could be attributed to the amount of sun exposure(7).

Elderly woman's hands holding a cup of coffee

Does the sun really cause skin cancer?

Beyond simply aging your skin, sustained and repeated exposure to UV radiation creates cumulative damage to your skin that can lead to skin cancer.

Skin cancer is the most common type of cancer in the world, with 1 in 5 Americans expected to develop skin cancer by the time they are 70 years old(8). According to the Skin Cancer Foundation, only about one percent of all skin cancers are melanomas, which is the most deadly form of skin cancer. Melanoma is cancer that affects the melanocytes of the skin and it has the ability to spread cancer to other organs in the body. The less serious forms of skin cancer include basal cell carcinoma and squamous cell carcinomas. Skin cancers are usually treatable if caught early.

The biggest risk factor for developing skin cancer is UV radiation, with the most likely exposures coming from time in the sun or use of tanning beds and UV lights(4). Therefore, it is important to remember that the biggest risk in skin cancer is something that you can directly control.

Man sitting outside in the sun with sunglasses on

How much sun per day is healthy?

Our bodies need sunlight to manufacture vitamin D. The commonly cited facts about sun exposure and vitamin D production in the skin come from a small study of 15 elderly patients who were tested for their vitamin D levels while being exposed to sunlight(9). The patients, who formerly went outside very little, were exposed to sunlight on their balcony for 0, 15 or 30 minutes daily over a four week period. The 30-minute group experienced a significant increase in their vitamin D levels, up by 7.4 micrograms compared to their base levels.

Often repeated, this result has led to the belief that 15-30 min of sun exposure several times a week is important for vitamin D production. Many people have been concerned that the use of sunscreen will lead to vitamin D deficiency.

However more recent science demonstrates that sunscreens are not interfering with vitamin D production. A 2019 systematic review of all experimental studies, field trials and observational studies on sunscreen and vitamin D production could not find evidence that use of sunscreen significantly decreased vitamin D levels(10).

Another 2019 study involving 59 volunteers looked at the effects of using sunscreen on vitamin D production during a one week vacation in a high sun exposure/high UV-index setting(11). The results showed that vitamin D synthesis was not disrupted by the use of sunscreens for the volunteers spending time in the sun.

These studies demonstrate that the commonly held belief, that sunscreen prevents the production of vitamin D by the skin, is not supported by science. Instead, the lack of sunscreen use is increasing the risk of skin cancers which are preventable diseases.

There is no such thing as a healthy tan

It is also a common misperception that a suntan, which is your body’s natural response to UV exposure, provides enough protection from the sun to prevent sunburn and further skin damage. A suntan only provides a Sun Protection Factor (SPF) of between two and four(3), whereas most sunscreens today provide SPF of 15 to 100. What does that mean?

People sitting out at the beach in the sun

Using sunscreen - SPF explained

Sunscreen can extend the amount of time you can spend in the sun without getting a sunburn. The efficiency of the sunscreen you choose is identified by its SPF number which is listed on the bottle.

What is SPF?

Sun Protection Factor (SPF) is a system of describing how much protection you are getting from UVB radiation, which is the main type of UV that causes sunburns. The number itself tells you how many minutes you can spend in the sun while accumulating an equivalent dose of UVB radiation as if you were unprotected in the sun for one minute(12).

Darkening of the skin (a suntan), which itself is a form of UV skin damage, provides an SPF of only two to four. That means that a tan lets you stay two to four minutes in the sun compared to only one minute unprotected. That is not much of a difference.

Translated to one hour, your tan at SPF of two to four means you are receiving the equivalent of 15 to 30 minutes of unprotected sun exposure.

Using sunscreen, however, blocks more UVB radiation, thus allowing you to spend more time in the sun without accumulating the same level of UV damage to your skin, and thereby avoiding both sunburns and increasing skin cancer risks.

An SPF 15 sunscreen allows you to spend 15 minutes in the sun during which you accumulate only a one-minute dose of UVB radiation. After one hour using SPF15, you have been exposed to the equivalent of four minutes of unprotected UVB radiation. Your tan simply cannot compare!

The chart below shows the common sunscreen SPF ratings and the equivalent UVB dose accumulated after one hour of use.


Chart breaking down the amount of sun protection from varying SPF levels


Protect yourself!

There are many ways to enjoy the sun without damaging your skin or creating a long term risk of skin cancer.

The World Health Organization recommends limiting sun exposure between 10 a.m. and 4 p.m. when the sun’s radiation is the strongest(13). If you cannot avoid being outside during this part of the day, then the universally called for precautions include(13):

  • Using a broad-spectrum sunscreen with SPF 15 or higher(14) that is applied a half hour before sun exposure and reapplied every two hours or according to the sunscreen label
  • Wearing protective clothing, hats, and sunglasses which block UV radiation
  • Seeking shade
  • Avoiding the use of tanning tables and UV lamps.

While limiting your exposure to the sun is your first line of defense against skin damage, healthy skin also needs to be supported from the inside out.

Grapes growing on a vine in the sun

What are the best supplements for sun-damaged skin?

A diet rich in dark leafy greens and colorful fruits and vegetables provides antioxidant vitamins and plant compounds that help your skin to repair itself from sun damage. A 2020 review of the science involving antioxidants and plant compounds that protect the skin from damage associated with the sun, and with aging, highlights the following nutrients(15):

  • Antioxidants: Vitamins A, C and E
  • Colorful plant compounds: Carotenoids, Resveratrol, Pycnogenol
  • Probiotics


Antioxidants are compounds that form part of your skin’s defense mechanism against damage from free radical ions. Free radicals form when oxygen, which is normally made up of two bonded oxygen atoms, splits during oxidative stress into two charged ions(16). These charged oxygens can trigger chain reactions that damage cells and tissues in the body. Therefore an “anti” oxidant is a compound that can bind with the reactive oxygens and neutralize them so they stop causing damage.

Vitamin C is the most abundant antioxidant and it can work alone or in combination with other antioxidants like vitamin E to protect and help repair sun-damaged skin (15). Vitamins A (or its precursor beta-carotene), C and E can be taken both topically and orally to support skin damage repair.

Plant compounds

Colorful plant compounds provide essential nutrients and cofactors necessary for repairing damaged skin. Carotenoids are important precursors for the synthesis of vitamin A in the body, and they are found in yellow, orange and red fruits and vegetables. The four major types of carotenoids have all been found to protect against sun damage and aging of the skin, and include: Beta carotene, lutein, zeaxanthin, and lycopene(15).

Resveratrol is a plant compound found in red grapes, peanuts and berries, which has antioxidant and skin protective properties. However, this compound is quickly and easily destroyed, making it difficult to use in a topical treatment or oral supplement(15). More studies are required.

Pycnogenol is plant extract derived from pine bark that has been shown to increase skin elasticity and hydration(15). Use of this compound has been shown to reduce skin wrinkles.


Although it may seem counterintuitive,probiotic supplements that promote a healthy gut also promote healthy glowing skin(15). The relationship between inflammation reduction in the skin and healthy gut functions is only beginning to be understood(16).

Additional nutrients

Vitamin B-3 - nicotinamide

Clinical trials involving supplementation with B3, in the form of nicotinamide, have shown impressive cancer-fighting results. A double-blind, randomized, controlled study involving 386 patients at high risk for recurring nonmelanoma skin cancers received 500 mg of nicotinamide twice daily or a placebo for 12 months(17). The treatment group showed a 23 percent reduction in new nonmelanoma skin cancers after one year.

A 2020 review of the safety and use of Nicotinamide in skin cancer trials showed that even at therapeutic doses over one gram/day, this form of B-3 was well tolerated, with few side effects, and produced significant reductions in skin cancer rates(18).


Collagen is a form of protein made by the body that is important for healthy resilient skin. A 2020 double-blind, placebo-controlled study of 36 post-menopausal women demonstrated a significant improvement in sun-exposed skin elasticity after only four weeks of oral supplementation with collagen hydrolysate(19).

In Summary

Summer sun exposure is part of a normal, healthy and active lifestyle, but it doesn’t have to include the unwanted side effects of sunburn and skin cancer risk. You can control the amount of damage the sun causes your skin by implementing sun safety behaviours like using SPF 15+ sunscreen, limiting your direct sun exposure during the hottest parts of the day, and by ensuring your diet provides all the nutrients your skin needs to effectively repair itself. Supplements can be an effective part of your summer sun protection plan, and can help keep your skin looking healthy and younger for longer.

Sue Senger - Contributing Writer, Physician’s Choice

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