Keep your Skin Safe this Labor Day Weekend: All about Sunscreen with Dermatologist Tim Loannides MD

Tim Ioannides MD
8 min readSep 9, 2020


As we move into the tail-end of summer, for many of us this year has simultaneously felt like it has flown by and dragged on endlessly. Thankfully, with the Labor Day weekend ahead we can take the opportunity to get some much needed relaxation in the final warm days of the year. A trip to the beach or lake is an ideal way to enjoy the three-day weekend, and if it’s a nice breezy day and you are able to maintain a fair distance from other people the transmission risk will be relatively low. In fact, as long as you are following proper social distancing measures, the biggest risk to your health you’ll find on the beach is from the sun.

Skin cancer is the most common cancer both in the United States and worldwide. More than two people die of skin cancer in the United States every hour, and one in five Americans will develop skin cancer by the time they are 70. In addition to this, having just five or more sunburns in your lifetime doubles your risk for melanoma. In addition to the health risks, an estimated 90 percent of skin aging is caused by the sun, and people who use sunscreen with an SPF of 15 or higher daily show 24 percent less skin aging than those who do not use sunscreen daily. Even an SPF of just five daily reduces your lifetime sun exposure by 50 percent by the time you’re 70, so whether you’re headed to the beach this weekend or a socially-distanced backyard barbeque it’s important to lather up on the sunscreen.

There can be a lot of questions and persistent myths when it comes to sunscreen, and. Tim Ioannides M.D. of Treasure Coast Dermatology in Florida has worked hard in his career to debunk them. Starting out his career at a plastic surgery practice, Ioannides quickly decided that cosmetic procedures weren’t his cup of tea and left to start his own practice focused exclusively on the medical side of dermatology. Working in the county with the second highest rate of skin cancer in the United States, he emphasizes to his patients that while skin cancer is the most common type of cancer Americans are diagnosed with, it is also one of the most preventable.

Below, we explore the basics of sunscreen and some of the most common myths pertaining to it.

How does sunscreen work?

As stated before, skin concerns like dark spots, wrinkles, and sagging skin that one would normally consider to be part of the typical aging process is actually almost entirely caused by our skin’s exposure to the sun. When the sun’s ultraviolet (UV) rays hit our skin it damages the fibers in the skin called elastin, causing the skin to sag, stretch, and lose its elasticity. It will also eventually begin to bruise and tear more easily over time and take much longer to heal. The lobster-red skin you get from a sunburn is actually your body producing an inflammatory process in response to sensing UV rays damaging the DNA in its cells. In addition to causing a painful sensation, skin damage from sunburns can also cause the DNA to mutate, allowing cells to acquire the ability to continue multiplying without the older cells dying off, resulting in skin cancer.

By using sunblock, you are better able to protect your skin from the powerful UV rays of the sun. Through a combination of physical and chemical particles, sunscreen is able to both block and absorb UV rays. Physical particles like zinc oxide and titanium dioxide reflect UV radiation from the skin, and chemical ingredients react with radiation before it penetrates the skin, absorbing the rays and releasing the energy as heat. There are two types of UV rays — UVA and UVB — and the best sunscreens protect your skin from both. UVB rays are the primary cause of sunburn and skin discoloration, and the longer wavelengths of UVA rays mean they penetrate deeper into the skin causing wrinkles and age spots. Both types of rays contribute to skin cancer development, and while SPF (sun protection factor) helps block the UVB rays, it doesn’t protect you from UVA rays, which is why it is important to make sure your sun protection has a four or five star UVA rating.

How should you apply it?

What many people don’t realize is the SPF rating isn’t an arbitrary scale of how powerful the protection is, but the number of minutes equivalent to one minute of unprotected sun exposure. For example, if you use sunscreen with an SPF of 30, it means every 30 minutes you are in the sun is equal to one minute in the sun without any protection. However, people tend to apply less sunscreen to their bodies than when it is tested in a lab, resulting in less protection that the SPF rating describes. That is why many people still get sunburned even when they apply sunscreen, as their sunscreen is only having half the impact it could. Most adults need about one ounce — or enough to fill one shot glass — to fully cover their body.

While spending an entire day out by the water means a lot more concentrated sun exposure, you should still be applying sunscreen to your face, ears, and neck every morning regardless of your activities for the day. You are at risk for dangerous sun exposure in many places you wouldn’t expect, such as from the side window of your car or even reflected off the snow in the winter. When you’re going to the beach or just remaining in the sun for an extended period of time, you should apply sunscreen 20 minutes before you expose your skin to the sun, and reapply at a minimum of every two hours. No sunscreen can claim to be waterproof, so if you go swimming you should reapply every time you return to the beach, even if the sunscreen is labeled as water-resistant or sweat-resistant. Sunscreen can also expire, so check the bottle to ensure you are using one that is still maximally effective.

Sunscreen myths debunked “The more expensive a sunscreen is, the better protection it will give me.”

When it comes to sunscreen, Dr. Ioannides says a higher price point doesn’t necessarily mean it’s going to offer you any better protection. Rather than looking for the priciest sunscreen or prettiest packaging, read the label and choose one that has a four or five star UVA rating in addition to a high SPF. UVA rays can cause skin cancer just like UVB rays, and so only protecting against one form of UV light isn’t ideal. It may even increase the likelihood of skin cancer later in your life, because in blocking UVB rays you are slowing down the rate your skin burns, making it possible for you to stay in the sun longer and potentially garner more UVA exposure than you would have previously. A good tip when shopping for sunscreen is to go for the products marketed toward children, because they tend to provide powerful, long-lasting protection.

“If I get a base tan, I will be protected from skin damage”

You now know the science behind sun damage and sunscreen, so you know that this statement is clearly false. In fact, there are numerous studies showing that using an indoor tanning bed greatly increases your risk for developing skin cancer. In fact, any history of indoor tanning increases the risk of developing basal cell carcinoma before age 40 by 69 percent. It is important to remember that while you may love your golden glow, a tan is a biological and physical sign that your skin is getting damaged. The International Agency for Research on Cancer — a branch of the World Health Organization — includes UV tanning devices in its Group 1 list of agents that are cancer-causing to humans, on which you can also find plutonium and cigarettes.

“Sunscreen contains chemicals that will harm my skin.”

Although news has been circulating about the FDA announcing it was asking for more information on sunscreen ingredients, this does not mean in any way that they are designating it as unsafe, and in fact continues to tell Americans they should apply sunscreen. All sunscreen ingredients are chemicals — a molecule is a chemical — but at the end of the day, UV exposure has been absolutely proven to cause most skin cancers and sunscreen has been proven to prevent it. If you feel you may be having a reaction to a sunscreen it is more likely to be caused by one of the inactive ingredients such as the emulsifiers or preservatives than the active ingredients used to prevent skin damage, but those with sensitive skin should try using one of the “physical” sunscreens that deflect the sun’s rays such as those containing zinc oxide or titanium dioxide, and look for formulas with as little ingredients as possible.

“You can’t get sunburnt on a cloudy day.”

Indirect exposure to UV radiation is definitely still possible on a cloudy day, or even in the shade. While clouds do reduce some of the sun’s UV rays, they don’t block those pesky UVA rays that penetrate deeper in the skin and cause wrinkles. In fact, up to 80 percent of the sun’s UV rays can still pass through clouds. Similar to the reason that you may be less protected if you use a sunscreen only blocking one type of UV ray, you are actually more likely to get sunburnt on a cloudy day because the sun’s rays feel less intense and you may not be as diligent with your sunscreen as a result.

“If you wear sunscreen you can’t get skin cancer.”

Unfortunately, even with regular and diligent sunscreen application you will still be exposed to some UVA and UVB rays that can have an impact over time. In fact, many dermatologists such as Dr. Ioannides stress that when thinking about sun protection, you should think beyond just sunscreen. The safest and most effective method for preventing skin cancer is to minimize your exposure to the sun in the first place. Additionally, covering your skin with clothes and hats are also an extremely effective method for protecting your skin.

Thankfully, when caught early skin cancer is very treatable. That’s why it’s extremely important to perform regular checks on your body for any skin damage or irregularities. Set a reminder on your calendar once a month to check your body from head to toe, looking out for potentially cancerous small changes. Anything new, changing, or unusual should be noted and potentially checked on by a physician, but in particular keep an eye on growths, moles, spots, and open sores.

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Originally published at on September 9, 2020.



Tim Ioannides MD

Dr. Tim Ioannides is the founder of Treasure Coast Dermatology located in Port Saint Lucie, Florida