Sunscreen can be confusing. SPFs, UVA and UVB rays, expiration dates and brands quickly becomes overwhelming. Carey Bligard, MD, UnityPoint Health, breaks it down so we have tips to keep our skin safe and healthy.
How Much SPF Do You Need?
Higher sun protection factor (SPF) doesn’t mean you apply it less. Both sweating and swimming wash off sunblock.
In fact, there is some controversy over SPF numbers. Some researchers suggest anything higher than SPF 50 doesn’t have any additional benefit. But another study suggests for people with a lot of sun exposure and risk of burning, a higher SPF can help. Either way, it’s best to go with an SPF of 30 or more.
Tip: Pick an SPF of 30 or more and reapply every two hours while outdoors.
What is the Difference Between UVA and UBA Rays?
The sun naturally produces UV (ultraviolet) radiation. Ultraviolet A (UVA) has a longer wavelength and ultraviolet B (UVB) has a shorter wavelength.
- UVA. UVA is less intense outdoors, but it’s just as strong at 8 a.m. as it is at noon. It’s present year-round and goes through window glass. UVA also goes deeper in your skin, which can cause wrinkles because it damages the collagen and elastic tissue.
- UVB. UBV intensity fluctuated and is stronger late morning and early afternoon. UVB is most often connected to damaging the top layers of the skin – like a sun burn. The SPF in your sunscreen tells you how much UVB protection you’re receiving.
Both UVA and UVB can cause skin cancer. They also both get through clouds, so make sure to apply skin protection even when it’s overcast.
Tip: Get a broad-spectrum product to protect yourself against UVA and UVB.
Does Sunscreen Really Expire?
Sun protection products do expire. They can also break down when kept in a hot car or golf bag. The expiration date doesn’t mean you have to immediately throw the sunblock out. But you should be putting it on your list of things to get at the store. If your product begins to separate and form a clear, oily layer, throw it out. Those products won’t give you predictable protection.
Tip: Use a marker to write the date on a new tube/bottle. Toss it after the one-year mark.
Sunscreen vs. Sunblock: Is it All the Same?
Sun protection products work with physical and chemical blockers.
Sunblock/Physical Blockers. Physical blockers sit on top of the skin and don’t allow the UVA and UVB rays from the sun to get in. Because physical blockers don’t enter the skin, they can’t cause allergic reactions, and they don’t irritate the skin or eyes. These products include active mineral ingredients, like zinc oxide and titanium dioxide. Because the minerals are not reactive with the skin, they are often used in “sensitive skin” and children’s products. Beware, since it sits on top of the skin, it wipes off more easily. One big perk, these products start working immediately once applied.
Sunscreen/Chemical Blockers. Chemical sunscreens soak into your skin cells. They work to inactivate the UV rays entering the skin turning it from electromagnetic waves into heat, which isn’t harmful to the skin. The higher the SPF, the more chemicals get into your skin, giving you a chance to develop allergies or irritation. Allergies to sunscreen often look like a bad sunburn. Make sure to apply these products at least 20 minutes before going outdoors.
Tip: Some products have both physical and chemical blockers. Overall, it’s your safest bet to apply all products 20 minutes before going outside to ensure maximum benefit.
What are Some Sunscreen Chemicals to Avoid?
The chemicals in sunscreen can seep into the bloodstream. A 2019 study found concerns around oxybenzone and avobenzone. The research found these related substances may have hormonal impacts when absorbed into the bloodstream. It’s important to note the research was performed in a small group of people. Experts say additional, broader studies are needed on this topic.
Due to the potential for hormonal effects, pregnant individuals may want to avoid products with oxybenzone and avobenzone during pregnancy. There are no studies about the effects of these two chemicals during pregnancy, but it’s always a good idea to avoid any potential risks. That being said, it's still very important for pregnant individuals to protect their skin. Instead, consider sticking with a sun protection product with physical blockers like zinc oxide or titanium dioxide.
Tip: If you are concerned, select products without oxybenzone and avobenzone.
Why is it Important to Wear Sunblock while Pregnant?
It’s always important to protect your skin, even during pregnancy.
One downside to sun exposure during pregnancy is elevated pregnancy hormones can cause some women to develop blotchy brown spots called melasma in sun-exposed areas, most commonly the face. These spots may fade away after delivery, but they don’t disappear in all women.
Tip: While pregnant, be especially diligent to apply sunblock on the face to avoid blotchy brown spots called melasma.
When Can Babies Wear Sunblock?
Babies shouldn’t wear sunblock of any kind until they’re six months old. The reason is they have fewer protective dead skin cell layers on the outside of their skin. This is what prevents things on the outside from getting in through their skin. After six months of age, the only sunblock safe for young children are zinc oxide and titanium dioxide, which are physical blockers.
Tip: Select products for babies without fragrances to reduce the likelihood of allergies.
Do All Skin Colors and Types Need UV Protection?
Everyone needs to protect their skin. People with dark skin have some natural protection from the sun, but they can still get sunburns, wrinkles and skin cancer. If you’re worried about dark spots caused by hyperpigmentation, sunscreen can help with that, too.
Tip: All skin colors and types should use a daily sun blocking face lotion year-round.
What are Doctor Recommended Face Protection Products?
My favorite sunscreen/lotion for the face works well from dry, oily and rosacea prone skin. It’s CeraVe Ultra-light Moisturizing Lotion. It moisturizes without the use of any oil, making it a good option for all skin types. It also has a SPF of 30.
If you need more moisture, or have particularly dry skin, try CeraVe’s Facial Moisturizing Lotion with an SPF of 30 or Neutrogena Oil-free Moisturizer with SPF 35.
Tip: Regardless of what product you use, apply moisturizer right after drying your face. Your skin should still be a little damp when your lotion goes on.
Can You Get Cancer if You Wear Sunscreen?
Using sun protection should be a life-long habit to prevent skin cancer, but it’s not a 100% guarantee. I’ve seen basal cell carcinoma (the most common skin cancer) on completely non-sun exposed body areas. I’ve also seen malignant melanoma (a potentially deadly skin cancer, which is becoming more common) on areas normally covered with clothes or inside the mouth or eyes.
Skin cancer is from an accumulation of sun exposure, not from a single sunburn, however, a severe, blistering sunburn doubles your risk of skin cancer. Your DNA in your skin cells develops breaks from UV exposure, and there are repair mechanisms that fix most of them. But you gradually collect more abnormalities until the cells become cancerous. If your immune system isn’t functioning properly and doesn’t get rid of this cancerous cell, it grows and becomes visible as skin cancer.
In general, people with darker skin have lower rates of skin cancer than those with lighter skin. However, those with darker skin are typically diagnosed with skin cancer at a later stage, meaning outcomes are worse.
Tip: Talk to your doctor if you have any questionable spots on your skin.
Is There Such a Thing as a Heathy Tan?
No. Suntans are your skin’s way of telling you your skin cells are getting radiation damage from UV rays. If you notice tanning or tan lines, it’s a hint you’re not using enough sunscreen.
Tip: Besides applying more sunscreen, consider additional protective steps, like wearing floppy or big-brimmed hats or UV protective clothing.
Does Sunblock Prevent Vitamin D from Absorbing?
Vitamin D isn’t absorbed from the sun. It’s made by the body and requires UV light to trigger the reaction in the body that creates vitamin D. You only need 10-15 minutes of direct sunlight to reap the benefits. So, while sunscreen can block the creation of vitamin D by the body, you still shouldn’t go outdoors without it, especially if you’re going to be out more than about 10 minutes.
Practically speaking, if you’re enjoying the pool all day, your sunscreen will wear off a bit at some point, allowing enough UV rays in to provide the vitamin D boost.
Tip: Try adding foods rich in vitamin D or a supplement instead of more time outdoors.