Skip to content

From Stanford: Tips on Summer Skin Care

Source: Stanford Report, June 20, 2024

Summer is rapidly approaching and while the sun can feel great on your skin after a long and rainy winter, the health effects of the sun on your skin can be a cause for concern. But Zakia Rahman, a clinical dermatologist at Stanford Health Care and affiliate faculty at the Stanford Center on Longevity, wants people to know that keeping your skin safe can be a lot simpler than it seems.

“It’s not about vanity. It’s about vitality,” said Rahman. “We’ve had the greatest increase in human life expectancy, which means that we need to live, work, and take care of ourselves for a long time. And people do want to take care of their hair, their skin, their nails. I think that’s a good thing.”

Here are some of Rahman’s top tips for summer skin care:

1. Consider your clothing 

Typically, people think of sun coverage as a hat and sunglasses – most people don’t want to wear long sleeves in the summer. But Rahman recommends that people invest in clothing with Ultraviolet Protective Factor (UPF). She keeps a UPF long-sleeve shirt, gloves, and hat in her car to wear when she’s driving and for use at the end of her trip. UPF protective clothing has been popular for years in Australia where the ozone layer is thinner and the awareness of skin cancer prevention is mainstream. However, skin cancer is the most commonly diagnosed cancer in the United States and nearly 5 million people are treated for it every year, according to the U.S. Department of Health and Human Services.

All clothing does have a bit of sun protection, but if the weave isn’t tight enough or if the material has been washed a lot, the protection factor goes down. “If you take a white T-shirt that’s been washed a bunch of times, it’s possible to get a sunburn even under your clothing,” said Rahman. UPF-rated clothing, hats, and sunglasses are available in many retailers now and can protect against sun-related UV damage, including skin cancer and cataracts.

2. Be sweat-smart

Hot summers lead to lots of sweating, which can lead people to want to dress in shorts and tank tops. Rahman says that loose-fitting long sleeves and pants can keep airflow going over your body, making the cooling effect of sweat work better. “Evaporative cooling is the main way our bodies control our temperature,” said Rahman.

In the United States, eczema rates are higher than in the rest of the world – dry, scaly rashes can come about as a result of taking showers that can break down the skin barrier. And when people are sweating, they’ll often take showers. Rahman said, “If you do take a shower every day, you should only soap up the areas with apocrine glands.” Apocrine glands are ones where the sweat and bacteria mixture can cause body odor, which are located in the armpits and groin.

And don’t forget to moisturize. In winter, indoor heaters can cause dehydration. But summer is also a great time to moisturize, and then lock it in with hydration. “We are losing a lot of fluids through sweating. In order to replenish our entire body and all our skin, we have to be really, really good with hydration,” said Rahman.

3. Know your sunblocks and sunscreens

Both sunblock and sunscreen are useful for providing protection against UV damage, but what is the difference between the two? They differ in ingredients and the mechanisms of how they protect the skin from UV damage. “Sunscreen is a chemical blocker. It absorbs the UV light particle and converts it to heat,” said Rahman. “On the other hand, sunblock reflects the light and doesn’t absorb the UV light.”

For most people, it’s a matter of preference which one you choose. In 2021, the FDA released its final order on OTC sun protection guidelines, which stated that only zinc oxide and titanium oxide were GRASE (generally recognized as safe and effective). These are physical blockers. However, sunscreen chemicals are still used in many products and contain ingredients such as avobenzone, homosalate, octisalate, and octocrylene.

Although the FDA considers titanium dioxide or zinc oxide the only GRASE ingredients, these products can result in a whitish cast on the skin, which is more obvious on people with more melanin. This can be a non-starter for most people and creates what Rahman feels are unfair disadvantages in adoption of sun protection. For that, Rahman says tinted sunscreens can look better aesthetically and add protection from visible light, which is known to worsen pigment problems, such as melasma or hyperpigmentation from acne. Heat itself can also worsen pigmentation, so sunblock can be better for those worried about hyperpigmentation – because it doesn’t cover UV light to heat (whereas sunscreen does).

And if sweating causes your sunblock or sunscreen to get in your eyes? Rahman has the same issue, and her hack is to wear sunscreen from the cheeks down, then put on a wide-brimmed hat to cover the rest.

4. Choose wisely and apply properly

With so many products and price points out there, it can be hard to choose what’s best. Rahman emphasizes that it’s not necessary to buy top-of-the-line products to get what’s necessary for your skin. Even products like topical retinoids and vitamin C topicals – which can help reverse premature signs of skin aging caused by the sun – might not be necessary for everyone. “I think a $20 sunscreen may be as good as one that’s $400,” said Rahman. “A gentle cleanser, a moisturizer, and sun protection – those three things together will give you 99% of what you need for your skin.” There are a variety of products at numerous price points to suit personal preferences that are better for our skin than using nothing at all.

And buying higher SPF isn’t necessary for most people, says Rahman, because SPF 15 already provides about 94% protection from the sun, while SPF 30 provides 98%.

The best way to get the most out of whatever you use is to ensure you get the correct thickness of the product on your skin. Most people apply about one-third to one-half of the thickness needed to get the SPF rating. That’s why dermatologists often recommend higher SPFs – if you don’t apply the right thickness of SPF 30, you might actually be reducing its efficacy to an SPF 15. “A double application, where you put some product on and then wait for a couple minutes, then do a second application will make sure that you can get the right thickness,” said Rahman.

 

5. Do what works for you

As much as Rahman emphasizes skin protection, she understands that people have different priorities. “I’ve heard sometimes from my patients that the recommendations I have would stop them from doing things they enjoy – I don’t want people to do that. I want people to understand that you can do it in moderation and still enjoy your life.”

She also points out that different people have different sun protection and skin care needs. For example, people with brown eyes are more likely to get cataracts, meaning UV sunglasses are especially helpful. Or people with short hairstyles are more susceptible to sun damage on their head and ears. So, someone’s regimen may be entirely distinct from anyone else’s since it corresponds to their needs.

While a lot of skin care decisions are determined by outward factors – visibly “younger” skin or avoiding unfashionable cover-ups – Rahman does encourage everyone to consider the bigger picture and how taking care of their skin can best support a happy, healthy life.

“True beauty is an inside job,” said Rahman. “As long as we understand that and focus on the things that matter – those should take precedence over trying to look perfect.”

Rahman is also a clinical professor of dermatology in the School of Medicine.