Sunscreen should be the last – not the first – line of defense to fend off the sun’s harmful effects

A little sun goes a long way in causing permanent skin damage

It’s not just sun-worshippers basking on beaches and in backyards who should heed warnings about the damage the sun can cause.

Physicians at the University of Michigan Health System say everyone should beware. Any amount of unprotected sun exposure – for example, the walk from the car to the grocery store entrance – can contribute to genetic changes in the skin and lead to premature aging, brown spots, wrinkles, sagging skin, and even skin cancer.

“The sun damages the skin every single time it hits the skin,” says John Voorhees, chair, Department of Dermatology, U-M Medical School. “It’s simply a matter of degree. So, a tiny bit of sun gives you a tiny bit of damage and a little more gives you a little more damage and the problem is that it accumulates over time, causing the damage to be permanent.”

The “healthy” tan that many people long for is anything but healthy. In fact, Voorhees says that a tan is the skin’s way of saying that it’s been damaged and the darkening is the skin’s way of providing its own sunscreen to block out further rays. Although a tan does provide a small amount of sun protection – a sun protection factor, or SPF, of about two – that amount of protection is inadequate to prevent serious sun damage.

Many people think that if they do not get a sunburn, that they’re home-free. “That’s not the case at all,” Voorhees says. “A sunburn is simply an indication of very gross, bad damage.”

Sun protection is even more important for children.

“It is believed by many that melanoma, which is the worst form of skin cancer, is caused by exposure to sunlight when you’re very young,” Voorhees says.

Many believe that freckles just appear in children naturally. But in fact, Voorhees says, the majority of freckles, if not all, are sure signs of sun damage. “When you see that occurring in a child, of course, it’s too late for those spots, but certainly that person needs tremendous sun protection.”

Sun exposure causes damage to the genes in the skin, Voorhees says. And although the body has a mechanism that repairs the vast majority of the damage that occurs, it’s not a perfect fix and some of the damage always remains. A scar, called a solar scar, is left behind.

“You can’t see these either in a microscope or with the naked eye,” Voorhees says. “But, after exposure, after exposure, after exposure – maybe 100, 200, 500 exposures – these invisible scars in the skin coalesce to become a scar that you can see. That causes a wrinkle, or sagging skin, and essentially, you look old before your time because you have accelerated the aging process in your skin.”

One or two damaging events are not enough to give someone skin cancer. But researchers have found that as the skin is subjected to more and more damaging events, the genes in the skin are mutated permanently.

“And if you hit the right gene with the sun, you can end up with skin cancer,” Voorhees says. “And skin cancer is the most common cancer in humans by a large margin.”

Voorhees explains that the sun has some benefit. It helps to form Vitamin D that promotes the absorption of calcium and strong bones.

“One of the best protections is staying out of the sun during the peak brightness of sun from about 10 a.m. to 2 p.m.,” he says. “The second key item is when you’re outside at any time, that you stay in the shade. And the third thing is to wear protective clothing; a large hat and long-sleeved shirts.”

He emphasizes that, “if you cannot avoid the sun or wear protective clothing, then use sunscreen as a fallback. This is the opposite of what most people do. They use sunscreen first and then, if somehow they feel too hot or the sun appears too bright, they will go under a tree for a period of time or put on a hat. That is not the way it should be done.”

Sunscreens are not as effective as most people would believe, Voorhees says. The standardized tests used to determine SPF often use a larger amount of sunscreen than anyone would use when applying it to themselves.

“The problem is, that it’s been shown by experimentation and by actual study that the average person puts on their skin somewhere around one-third to one-quarter the amount that is necessary to give them the SPF factor on the bottle,” he says. “So, if you purchase a bottle of sunscreen that has an SPF of 40 and you put on one-quarter of the amount that it was tested under, you will be getting an SPF of 10 on your skin.”

Voorhees does recommend that people look for sunscreens that are broad-spectrum, blocking out both UVA and UVB. But, people should read the fine print too.

“Be sure that what you’re about to buy contains either Parsal 1789 or avobenzone,” he says. “Those two terms describe the very same chemical. As long as you have one of those along with an SPF of 30 or greater, that’s the best that you can do – and apply it liberally.”

Facts about sun exposure:

Excessive sun exposure can cause your skin to age prematurely, become leathery, wrinkled, and in some cases, may cause skin cancer.

The effects of the sun are cumulative over a lifetime. People usually receive most of their sun exposure by the age of 18, so protecting children from the sun is very important for their long-term health.

Researchers and physicians recommend staying out of the sun during the peak brightness of sun which is from about 10 a.m. to 2 p.m. When outside at any time, stay in the shade and wear protective clothing. The last line of defense should be sunscreen.

Sunscreens should be at least SPF 30 and broad-spectrum, blocking out both UVA and UVB. Read the fine print to ensure that one of the following two ingredients is present: Parsal 1789, or avobenzone. Apply sunscreen liberally!

Skin cancers are now the most common type of cancer. The most common type is called basal cell carcinoma. It is a slow-growing cancer that usually does not spread to other parts of the body. The second-most common skin cancers are called squamous cell carcinomas. They grow more quickly and have been known to spread. The least common form, malignant melanoma, is the most serious. It arises on or next to moles. If it’s not treated, it can spread – sometimes with fatal results.