UV Radiation

q8ghrfivc2 For a six billion-year-old star, the sun is certainly in the news a lot lately, mainly because it is still a source of uncertainty and confusion to many of us.

The center of this confusion is the sun’s ultraviolet A (long-wave) and ultraviolet B (shortwave) rays. Our understanding of exactly what kinds of damage each causes to the skin, and how best to protect ourselves, seems to shift every year as new research comes out. For example, it was once thought that only UVB was of concern, but we keep learning more and more about the damage caused by UVA. And new, improved forms of protection against UVA keep emerging. Keeping up with these new developments is a worthwhile challenge that can help all of us prevent sun damage.
What is Ultraviolet Radiation?

UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. It has wavelengths shorter than visible light, making it invisible to the naked eye. These wavelengths are classified as UVA, UVB, or UVC, with UVA the longest of the three at 320–400 nanometers (nm, or billionths of a meter). UVA is further divided into two wave ranges, UVA I, which measures 340-400 nanometers (nm, or billionths of a meter), and UVA II which extends from 320–400 nanometers. UVB ranges from 290 to 320 nm. With even shorter rays, most UVC is absorbed by the ozone layer and does not reach the earth.

Both UVA and UVB, however, penetrate the atmosphere and play an important role in conditions such as premature skin aging, eye damage (including cataracts), and skin cancers. They also suppress the immune system, reducing your ability to fight off these and other maladies.
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UV Radiation and Skin Cancer

By damaging the skin’s cellular DNA, excessive UV radiation produces genetic mutations that can lead to skin cancer. Both the U.S. Department of Health and Human Services and the World Health Organization have identified UV as a proven human carcinogen. UV radiation is considered the main cause of nonmelanoma skin cancers (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). These cancers strike more than a million and more than 250,000 Americans, respectively, each year. Many experts believe that, especially for fair-skinned people, UV radiation also frequently plays a key role in melanoma, the deadliest form of skin cancer, which kills more than 8,000 Americans each year.
UVA

Most of us are exposed to large amounts of UVA throughout our lifetime. UVA rays account for up to 95 percent of the UV radiation reaching the Earth’s surface. Although they are less intense than UVB, UVA rays are 30 to 50 times more prevalent. They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.
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UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (photoaging), but until recently scientists believed it did not cause significant damage in areas of the epidermis (outermost skin layer) where most skin cancers occur. Studies over the past two decades, however, show that UVA damages skin cells called keratinocytes in the basal layer of the epidermis, where most skin cancers occur. (Basal and squamous cells are types of keratinocytes.) UVA contributes to and may even initiate the development of skin cancers.

UVA is the dominant tanning ray, and we now know that tanning, whether outdoors or in a salon, causes cumulative damage over time. A tan results from injury to the skin’s DNA; the skin darkens in an imperfect attempt to prevent further DNA damage. These imperfections, or mutations, can lead to skin cancer.

Tanning booths primarily emit UVA. The high-pressure sunlamps used in tanning salons emit doses of UVA as much as 12 times that of the sun. Not surprisingly, people who use tanning salons are 2.5 times more likely to develop squamous cell carcinoma, and 1.5 times more likely to develop basal cell carcinoma. According to recent research, first exposure to tanning beds in youth increases melanoma risk by 75 percent.
UVB
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UVB, the chief cause of skin reddening and sunburn, tends to damage the skin’s more superficial epidermal layers. It plays a key role in the development of skin cancer and a contributory role in tanning and photoaging. Its intensity varies by season, location, and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as snow or ice, which bounce back up to 80 percent of the rays so that they hit the skin twice. UVB rays do not significantly penetrate glass.

Suncare on the Slopes

Higher altitude means increased levels of harmful UV exposure compared to sea level areas. UV exposure increases 8-10 percent with every 1,000 feet above sea level. At an altitude of 9-10,000 feet, UV may be 45-50 percent more intense than at sea level. In addition, snow reflects about 80 percent of the UV light from the sun, meaning that you are often hit by the same rays twice. This only contributes to the problem, further increasing the risk for skin cancer.

The combination of higher altitude and ultraviolet (UV) rays reflected by the snow puts skiers and snowboarders at an increased risk of sun damage and ultimately, skin cancer. More than 90 percent of all skin cancers are caused by sun exposure. It’s easy to associate winter with frostbite and windburn, but most people are unaware that UV rays can be even more damaging on the slopes than on the beach,it’s important to take proper precautions while on the slopes.

Both snow and strong wind can wear away sunscreen and reduce its effectiveness, so you have to take extra precautions. To protect your skin from the bitter cold, heavy winds and winter sun, follow these important sun protection tips:
• Use a broad-spectrum sunscreen with an SPF of 15 or higher whenever you spend time outdoors. Apply 30 minutes before hitting the slopes.Be aware that the sun’s reflection off the snow is strong even on cloudy days.
• Apply sunscreen liberally and evenly to all exposed skin – most skiers and snowboarders do not use enough sunscreen and therefore do not get the maximum protection.
• Use a more moisturizing sunscreen. Winter conditions can be particularly harsh on the skin.
• Be sure to cover often-missed spots: lips, ears, around eyes, neck, underside of chin, scalp and hands.
• Always wear a lip balm with an SPF 15 or higher. Lips are even more sensitive than most parts of the skin.
• Reapply at least every two hours, and more often after sweating or exposure to wind and snow.
• Carry a travel-sized sunscreen and lip balm with you on the slopes. Reapply on the chairlift, especially after a long, snow-blown run.

Cover up.

• Wear items like ski masks, which will cover most of the skin, leaving very little exposed to the wind and sun.
• UV-blocking sunglasses or goggles that offer 100% UV protection and have wraparound or large frames protect your eyelids and the sensitive skin around your eyes, common sites for skin cancer and sun-induced aging. The sun’s rays and glare can impair your vision, so it’s important to wear sunglasses or goggles to clearly see the terrain. Plus, it will increase your enjoyment and performance while skiing.
Be mindful of time spent in the sun, regardless of the season.
• Keep track of the time you spend in full sunlight. If possible, ski early in the morning and later on in the day, before 10AM and after 4PM. This helps avoid long lines and decreases the amount of time spent outdoors in the most intense hours of sunlight.

• If you are on the slopes for most of the day, take a few breaks indoors to reapply sunscreen.
• Drink plenty of water to avoid dehydration from the sun.
Enjoy the winter season, but be sure to take care of your skin to avoid the damage the cold season can cause.

The first organization in the U.S committed to educating the public and medical professionals about sun safety, The Skin Cancer Foundation is still the only global organization solely devoted to the prevention, detection and treatment of skin cancer. The mission of the Foundation is to decrease the incidence of skin cancer through public and professional education and research.

FAQ on Sunscreens and Sunburns

1. “How Much Sunscreen Should I Apply?”

The average user of sunscreen tends to use significantly less sunscreen than the amount required to achieve the SPF listed on the container.

2. “How Often Should I Apply Sunscreen When I’m Out In The Sun?’”

Many experts recommend that frequent application during sun exposure is required. However, a group of children were tested by spreading on 1 application of sunscreen to one side of their bodies, and four applications to the other.

They then spent 6 hours in the sun. One application provided the same level of protection as four applications, confirming the adequacy of a single daily application of a sunscreen in that situation.

3. “How Long Before Sun Exposure Should I Apply Sunscreen To My Skin?”

As molecules of sunscreen are present in their active state in the sunscreen, sunscreens work immediately upon application. The only reason for application early is to allow absorption into the skin so that the sunscreen is less likely to be washed off, should the person be entering the water. Even so, modern sunscreens are quite resistant to removal from the skin.

4. “Sun Protection Factor (SPF) – What Is It?”

SPF is the ratio of the minimal ultraviolet dose required to produce redness with and without a sunscreen. For example, if it took ½ hour for your skin to become sunburned without any sunscreen, then for a sunscreen that has a 15 SPF rating, you could stay in the sun for 15 times longer (or 7.5 hours) before you get sunburned. This is provided, of course, that you’ve applied the sunscreen properly so that you’re getting the prescribed protection.

5. “Reactions To Sunscreens?”

Sunscreens can be both an irritant and an allergen, though allergic reactions are rare. Irritant reactions, however, abound. One classic error in sunscreen application is to put a large amount of sunscreen on the forehead. Perspiration and gravity can cause the sunscreen to migrate down your forehead into your eyes, causing a stinging sensation. Some people attribute this to an allergic reaction and discontinue use. It’s also important to wash your hands after applying sunscreen, since rubbing your sunscreen covered finger near your eyes can induce an irritant reaction.

6. “Why Is It Important To Use Sunscreens During Childhood?”

It appears that a great deal of time can elapse between actual sun damage and the development of skin cancer or other skin problems like photoaging. Therefore, it is important to protect your skin from an early age when you are out in the sun.

7. “Sunscreens And The Elderly?”

Many elderly people can become quite obsessed by sun avoidance, and their quality of life can suffer. Sometimes, if they are diagnosed with an actinic keratosis or basal cell carcinoma, they can become anxious and almost leap from shadow to shadow. However, few of them are likely to develop new skin cancers from present sun exposure. As long as they are prudent about avoiding excessive sun exposure and protecting their skin to prevent sunburn, they can continue to enjoy time outdoors.

8. “Can Sunscreens Prevent Cancer?”

There is clear evidence that sunscreens are helpful in preventing actinic keratoses, which are warty lesions that can occur on sun-exposed skin of the face or hands. Research has shown that these lesions can develop into a cancer called squamous cell carcinoma, and that this is linked to a cumulative exposure to the sun.

However, there is surprisingly little evidence that sunscreens have much effect in preventing another kind of skin cancer called basal cell carcinoma, or for malignant melanoma. For malignant melanoma and for basal cell carcinoma, the character and timing, that is, the type of sunlight and your age at the time of the exposure to the sun appears to be more important than the cumulative dose.

Adapted from an article by David I. McLean, MD, and Richard Gallagher, MA.

How To Choose the Best Sunscreen

Sunscreen is quite effective in protecting the skin against the sun’s harmful UV rays when the proper SPF is used. Yet we see more and more sun damage and skin cancer mainly attributed to a lack of protection in early years of life. That is why it is very important to use sunscreen from the beginning.  It can be confusing because consumers have a such a choice between sun skin care – traditional sunscreen, organic sunscreen, natural sunblock that use all natural ingredients, and even sunless tanning lotions with SPF protection. Any time we hear the words “all natural,” we know that it is good for us. However, we also realize that there must be a reason why some of the same types of products do not contain all natural ingredients. Is it because they are better or because they are more cost-effective for the manufacturer to make? We have to take into consideration that there was a time in which our ancestors only had natural means to treat and prevent disease. Somewhere along the line we found more cost-effective ways to make products by creating man-made chemicals that got the job done. This happened with sunscreen.

People love to sunbathe and with the continuing reports that the sun is becoming more and more dangerous, the sunscreen market is booming. More people are protecting their children and themselves from the harmful rays that can cause skin cancer. No one wants to think of their children having to contend with such an awful disease, no matter how minor it may be if caught on time. But we love to go to the beach and we love to swim in our pools, so we have to take care of our skin in the process.

The truth is that you shouldn’t really have any more than 15 minutes of sun exposure each day in order to receive the necessary amount of Vitamin D. Any more than 15 minutes is what causes damage, so you need to use a sunscreen. A good organic sunscreen is going to be just as effective as a regular sunscreen and without any of the man-made ingredients. All of the ingredients are all natural, which means they are derived from plants. In other words, the ingredients are extracted from the wonders of nature that actually work.

The main difference between an organic sunblock and a regular sunblock aside from their ingredients is that organic sunblock will break down over time. However, if used consistently over the summer months, that shouldn’t matter because you’ll easily be able to use a majority of what is in the bottle if not all of it. However, when you look at the bottle of a regular sunscreen, you will notice that there are both organic and inorganic ingredients, so eventually regular sunscreen has to be disposed of anyway.

So if you want to spend more than 15 minutes in the sun, be sure to invest in a good organic sunscreen and apply it to all skin areas that are exposed to the sunlight. That way, you can still receive the benefits of the sun while protecting your skin from the harmful UV rays. You are also not putting inorganic ingredients on your skin. Everything that is inside a bottle of organic sunscreen is just as natural as you are.

Chloasma is a Common Skin Condition for Pregnant Women

Chloasma or the “Mask of Pregnancy” can cause blotchy discoloration on your face and splashes of darkened skin that may appear on the forehead, nose, and cheeks in a mask-like configuration on some pregnant women – more often in dark-skinned women.

What causes chloasma: Those mischievous pregnancy hormones are toying with you again, causing hyperpigmentation on many parts of your body. You might have noticed your freckles and moles are darker now, there’s probably a dark line down the center of your abdomen (the linea nigra), and your areolas are probably a deeper shade as well. (You might as well decide this is sexy.) Dark-skinned women usually notice such hyperpigmentation more, but light-skinned women aren’t off the hook completely – they too will get their fair share of darkening skin, though it may not be as noticeable.
Despite have clear skin most of their lives, many women find another “new experience” awaiting them once they discover a pregnancy. The beginning stages can be small and unnoticeable pimples – usually showing around the jaw line or forehead due to hormonal fluctuations.

Three main factors contribute to acne: increased oil production, clogged pores, and a bacteria called P-acnes. First, oil causes the dead skin cells to stick together, leading to a clogged pore, which is called a blackhead or a whitehead. Bacteria then moves into the pore, producing inflammation, which manifests as redness and pus. Addressing acne requires medications or treatments that decrease oil secretion, unclog pores, and kill bacteria.

As the pregnancy progresses, the acne will worsen. It is at this point, many women may frantically search for cures in their local drugstore or try home remedies. Perhaps they feel overwhelmed by the choices or confused by the long list of ingredients and decide to give up finding a solution. In some cases, the acne can grow to included pigmented or “age” spots as well.

All of these changes typically last the duration of the pregnancy and are due to hormonal changes and increased oil production, resulting in acne, while higher estrogen levels will activate skin color cells to make dark spots. This occurrence is so common in pregnancy that it’s been given the name “mask of pregnancy.” Sun exposure will exacerbate the issue further without a good sunscreen or sun protection, try to use organic sunblock.

Like many others, when facial skin suddenly becomes oily, the first reaction is to take away all moisture or anything ‘greasy’ that can increase the feel of oil on the skin layer.

Never fear, these again are temporary problems with easy fixes. First, stop using anything oil-based and switch to gel-based or water based sunscreens and lotion for the time being. Treat you skin as if it were the acne-prone, pigmented type and finally ask your doctor or dermatologist for a baby-safe acne treatment if the situation is really uncomfortable. Your skin should return to its previous condition soon after your baby is born.

• In the meantime – Eat foods that contain folic acid (you’ll also get plenty in your prenatal supplement), since studies have shown that a folate deficiency can be related to hyperpigmentation. Good choices include green leafy vegetables, oranges, whole-wheat bread, and whole-grain cereal.
• Stay out of the sun as much as possible and wear a natrual sunscreen of at least SPF 15 (sunlight can also intensify hyperpigmentation). A hat and long sleeves are a good idea if you’re fair-skinned, headed to the beach, or have a historically sensitive complexion.
• If you like, use a good concealer to cover particularly pesky spots, but skip bleaches or other chemically based lightening treatments until after you give birth. No peels or lasers, either.

Baby Sun Care Guidelines from the AAP

The best way to protect your baby is to keep your baby out of direct sunlight as much as possible, especially between 10 a.m. and 4 p.m., when the sun’s rays are strongest. Routinely dress him in a hat, lightweight pants, and a long-sleeved shirt for outings during the middle of the day. Tightly woven clothing protects better than loosely woven fabrics (to see how tight the weave is, hold the fabric up to a light – the less light that shines through, the better). Add UV-protective sunglasses if your baby will wear them. Use an umbrella, stroller canopy, or sun-protective tent to protect your baby while he’s outside.

Until August 1999, the American Academy of Pediatrics (AAP) recommended against using any type of sunscreen on babies younger than 6 months, because their skin’s ability to metabolize and excrete chemicals may not be fully developed. This recommendation has been revised somewhat.  You can use sunscreen on babies under 6 months if adequate clothing and shade aren’t available, but check with your pediatrician first.  If you use organic sunblock you can avoid chemical interaction altogether.  That doesn’t mean you should slather your baby in sunblock, though. Just apply a small amount of lotion to exposed areas.

For babies over 6 months, use a waterproof sunscreen designed for children. Choose a sunscreen labeled “broad spectrum,” which means it protects against both ultraviolet B (UVB) and ultraviolet A (UVA) rays. Zinc oxide and titanium dioxide sunscreens are good to use on particularly sensitive spots, such as the nose and lips.

The AAP and American Academy of Dermatology recommend an SPF of at least 15, but many experts recommend SPF 30 or higher for babies, and many baby sunscreen formulas have even higher SPFs. If possible, apply sunscreen 30 minutes before sun exposure and reapply it at least every two hours, especially if your baby has been playing in the water or has been sweating (even if the sunscreen is waterproof).

When trying a new sunscreen, do a patch test on your child’s back to make sure he doesn’t have a reaction to it. If he does develop a rash or redness at the test site, choose a hypoallergenic formula instead.

Sun Care Tips for Taking Your Baby in the Sun

When you take your bay outside you should understand how to keep them safe from the sun. Their skin is so delicate that the sun and wind can burn them easily. If there is any tanning on your baby’s skin it means that there is some skin damage. The mildest of sunburns is very painful for the baby and studies have shown that skin cancer is related to sunburn in childhood. Here are some tips to protect the baby from the sun:• Dress your baby up in long-sleeved T-shirts and pants made of cotton. This will be cool and protect the skin from the sun.
• Do not let your baby out in the sun especially at noon, as the sun is the strongest at this time.
• Use a sunblock every time you take the baby out. The sun protection factor SPF should be at least 15. You should reapply if your going to be out in the sun for over a couple hours
• Use a wide rimmed hat when you take the baby out. Sunshades and umbrellas are a great tool also.
• If your baby does get sun burnt give him a cool bath and apply an aftersun lotion. It is always safer to consult your doctor first.
• Ensure that your baby is drinking a lot of fluids. Whether it is breast milk or water especially if it is very hot so that he doesn’t get dehydrated.
• Sometimes babies can have a heat stroke due to over exposure to the sun. The common symptoms are vomiting, listlessness, headaches and drowsiness. Give your baby plenty of fluids and consult your doctor immediately.
• Remember to protect your babies from the wind too. Harsh wind can damage their delicate skin as well.

Sun care if your skiing or in high altitude

Higher altitude means increased levels of harmful UV exposure compared to sea level areas. UV exposure increases 8-10 percent with every 1,000 feet above sea level. At an altitude of 9-10,000 feet, UV may be 45-50 percent more intense than at sea level. In addition, snow reflects about 80 percent of the UV light from the sun, meaning that you are often hit by the same rays twice. This only contributes to the problem, further increasing the risk for skin cancer.The combination of higher altitude and ultraviolet (UV) rays reflected by the snow puts skiers and snowboarders at an increased risk of sun damage and ultimately, skin cancer. More than 90 percent of all skin cancers are caused by sun exposure. It’s easy to associate winter with frostbite and windburn, but most people are unaware that UV rays can be even more damaging on the slopes than on the beach,it’s important to take proper precautions while on the slopes.

Both snow and strong wind can wear away natural sunscreen and reduce its effectiveness, so you have to take extra precautions. To protect your skin from the bitter cold, heavy winds and winter sun, follow these important sun protection tips:

• Use a broad-spectrum sunscreen with an SPF of 15 or higher whenever you spend time outdoors. Apply 30 minutes before hitting the slopes.Be aware that the sun’s reflection off the snow is strong even on cloudy days.
• Apply sunscreen liberally and evenly to all exposed skin – most skiers and snowboarders do not use enough sunscreen and therefore do not get the maximum protection.
• Use a more moisturizing sunscreen. Winter conditions can be particularly harsh on the skin.
• Be sure to cover often-missed spots: lips, ears, around eyes, neck, underside of chin, scalp and hands.
• Read the ingredients to learn which active ingredients are protecting you. Try to use Zinc or Titanium and organic inactive ingredients. Organic sunblock can prevent complications some chemical sunscreens may cause.
• Reapply at least every two hours, and more often after sweating or exposure to wind and snow.
• Carry a travel-sized sunscreen and lip balm with an SPF of 15 on the slopes. Reapply on the chairlift, especially after a long, snow-blown run. Lips are very sensitive.
• Wear items like ski masks, which will cover most of the skin, leaving very little exposed to the wind and sun.
• UV-blocking sunglasses or goggles that offer 100% UV protection and have wraparound or large frames protect your eyelids and the sensitive skin around your eyes, common sites for skin cancer and sun-induced aging. The sun’s rays and glare can impair your vision, so it’s important to wear sunglasses or goggles to clearly see the terrain. Plus, it will increase your enjoyment and performance while skiing.
• Keep track of the time you spend in full sunlight. If possible, ski early in the morning and later on in the day, before 10AM and after 4PM. This helps avoid long lines and decreases the amount of time spent outdoors in the most intense hours of sunlight.
• If you are on the slopes for most of the day, take a few breaks indoors to reapply sunscreen.
• Drink plenty of water to avoid dehydration from the sun.

Enjoy the winter season, but be sure to take care of your skin to avoid the damage the cold season can cause.

A Couple Myths About Sunsceen and SPF

Sun protection has become a way of life for individuals, who are intent on keeping their skin healthy, and avoiding wrinkles and leathery skin. Getting sunburn repeatedly can increase your chance of getting skin cancer. Melanoma in children has been increasing each year! So it is important for us all to take a practical approach and properly use natural or organic sunscreen and develop healthy skin care habits. Surprisingly, not everyone knows how to apply sunscreen. Only a small percent of the population uses sunscreen protection and only half of those people apply sunscreen correctly. In addition, regardless of the SPF or what the label says, sunscreens must be reapplied every 80 minutes or less. Sunscreen users mistakenly believe that high Sun Protection Factor (SPF) sunscreen products will protect them all day with one application, when in fact; all sunscreens must be reapplied regularly.Two Sunscreen Myths

Myth: Sunblock provides total sun block.
Truth: No sunscreen blocks 100 percent of Ultra Violet (UV) rays. SPF 15 can protect against 93 percent. SPF 30 protects against 97 percent. SPF 50-60 shuts out 98 percent. The higher the SPF the more harsh chemicals are in the product.

Myth: An SPF 60+ sunscreen provides double the protection of an SPF 30 sunscreen.
Truth: This is exactly why the FDA is putting a cap on high SPFs. SPF 30 provides skin with 97% protection, where as SPF 60 provides skin with 98-98.6% protection. There is less than 1.6% difference in protection factor. A SPF 60+ needs more chemicals to achieve a higher SPF, potentially putting more toxins in your body.

The real confusion to consumers has been what a product can do and can’t do. There are a number of natural sunscreen products are available on the market today. The trick is to become educated! Do you believe that just because sunscreens are labeled “sweat proof” or “waterproof” that they are? Currently, the FDA is banning the word “waterproof.” Now the term, “water/sweat/perspiration resistant” is accurate, however; this only means the sunscreen offers SPF protection after 40 minutes of water exposure. The term, “very water resistant” gives 80 minutes of protection. So to be safe, use this basic rule of thumb: re-apply, re-apply, and re-apply!For people who don’t have a lot of time, especially parents, a trend today has been to use aerosol sunscreens because they find them easier to apply. However, people may not be effectively protecting their skin! While being applied, aerosol sunscreens can lose much of their protection during the transfer from the bottle onto the skin. This is because not all of the molecules land on your body.

Chemical Free Sunblock is Best

As humans, we are naturally meant to be in the sun. That been said, most of us have skin so it is better to protect our skin with sunscreen but also to be cautious not to allow too much exposure. It’s also ideal to choose a “physical” or “chemical-free” sunscreen made with zinc oxide or titanium dioxide – look for one of those ingredients on the label.  You can try to find one that uses natural or organic ingredients too.Unlike chemical sunscreens, which may cause irritation or allergic reactions because the skin absorbs the active ingredients, zinc oxide and titanium dioxide sit on top of the skin, forming a barrier against the sun’s rays. There’s no evidence chemical sunscreens are dangerous or toxic, but we just don’t know enough yet about how young children react to the ingredients. Also, sunscreens with zinc oxide or titanium dioxide start protecting as soon as you put them on, whereas chemical products need to be slathered on 30 minutes in advance so the skin has time to absorb them. Also make sure any sunscreen you use is labeled “PABA-free.” PABA was once widely used in sunscreens but now has been linked with skin irritation. Parabens have recently been exposed as a poor choice of synthetic ingredients as well. 

You may have heard you should look for a “broad-spectrum” product that protects against both UVA and UVB rays. Any sunscreen that contains the physical blocker zinc oxide or titanium dioxide will do this.

The sun protection factor (SPF) should be at least 15, but you generally don’t need to go above 30: Higher than that and you’re getting smaller and smaller amounts of added protection – which, in a chemical sunscreen, means a higher dose of unwanted chemicals. It’s fine to use a “children’s” sunscreen, but don’t go out of your way to buy one of these, since they’re usually no different from the adult versions.