Sunscreens: A Guide to SPF

By Rachel Lamont
Medical Esthetician & Owner of The Natural Art of Skin Care


We were taught in school the best anti-aging is prevention. So feed your skin healthy, vitamin rich skin care and continuously protect against daily environmental and UV light damage over the years. This will leave you with beautiful skin that will pass the test of time. So should everyone wear sunscreen? Yes! You should wear sunscreen to prevent skin cancer and premature aging. So let's make sure you pick the safest one! 
Firstly, what are we protecting against?

UVB Rays

Invisible rays are part of the energy that comes from the sun. UVB radiation causes sunburn, darkening and thickening of the outer layer of the skin, and melanoma, not to mention other types of skin cancer. It may also cause problems with the eyes and the immune system. 

UVA Rays

UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (called "photo-aging"), 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, located 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; This causes the skin to darken 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! 

What is SPF?

Most sunscreens list an SPF number on the label. SPF stands for "sun protection factor," and is a measurement of protection from only UVB rays, which are the ones that cause redness and sunburn.

What is an SPF Rating?

Sun Protection Factor (SPF) indicates how long it will take for ultraviolet B (UVB) rays to redden your skin when you use a sun protection product, compared to how long the skin would take to redden without the product. So, the SPF number gives you some idea of how long you can stay in the sun without burning. For example, if you normally burn in 10 minutes without sunscreen and you've applied a liberal dose of a sunscreen with an SPF number of 15, you should be protected from sunburn for 150 minutes. This does not mean that you are protected from other radiation damage. A broad spectrum sunscreen is required to give protection in the UVA range as well. An SPF rating does not measure Ultraviolet A (UVA) protection.

UVA rays are considered even more dangerous, as they penetrate skin more deeply and are linked to skin cancer. But SPF does not measure a sunscreen's protection against UVA rays-only UVB rays. To further explain the SPF measurement, it is the difference between the amount of sunlight that causes redness in sunscreen-protected skin, and the amount that causes redness in unprotected skin. A sunscreen with an SPF of 15 theoretically gives you 15 times the minutes to stay out before you burn. For example, if you usually burn in 10 minutes, and you apply an SPF 15 product, you can stay out for 150 minutes. There are some problems with this equation though. It makes people believe that an SPF of 30 would allow them to remain twice as long in the sun as an SPF 15. In truth, an SPF 15 blocks about 93 percent of UVB rays, while an SPF 30 blocks about 97 percent, and an SPF 50 about 98 percent. So going higher and higher doesn't necessarily create more protection after a certain point. In addition, these numbers have nothing to do with UVA rays, so people who slather on an SPF of 50 and stay out in the sun for hours are likely to suffer even more severe skin damage if they don't have a "broad spectrum" sunscreen that protects from both UVA and UVB rays. Studies just don't support the idea that a higher SPF provides more protection. In addition, high SPF products are often made with greater percentages of chemical ingredients, which may be linked to hormone disruption, trigger allergic reactions, and potentially expose you to more free-radical damage. So I always suggest that everyone reapplies their SPF every 2-3 hours if you are continually out in the sun. Also a hat and some light covering clothes are always helpful protectors.

So what makes a safe Sunscreen?


Chemical Sunscreens vs. Physical Sunscreens

For many years now, people have been categorizing sunscreens into two groups—physical and chemical. Chemical sunscreens are made in the laboratory from synthetic ingredients. Some of the most popular chemical SPF ingredient options are cinnamates, oxybenzone, PABA and more. They reduce sun damage by absorbing UV rays that would otherwise be absorbed into the skin and cause damage. Studies have shown that a number of chemicals in sunscreens, such as PABA, cinnamates, oxybenzone, and more can react with the sun’s rays to create damaging free radicals, which may actually increase the risk of skin cancer.

Chemical sunscreens have also been linked with hormone disruption. Research has found that they can act like estrogen in the body, throwing natural hormones off-balance. In a study of six common sunscreen chemicals, five acted like estrogen, causing an increase in human breast cancer cells.  This is very scary stuff considering these products are suppose to help us prevent cancers and keep us healthy and safe! Which, to me, raises important questions about unintended effects on human health from frequent sunscreen application. The most worrying is oxybenzone, which is added to nearly 70 percent of the non-mineral sunscreens, according to the EWG’s 2016 sunscreen database.

Another concern with these sunscreens is that they have the potential to penetrate deeply into skin, getting inside the body. A 1999 study shows for instance, that all sunscreen agents tested penetrated into the skin, with benzophenone-3 (oxybenzone) passing through in significant amounts. In 2008, the Centers for Disease Control and Prevention (CDC) reported that nearly all Americans were contaminated with oxybenzone, which has been linked with hormone disruption and allergies. This is not good!

EWG recommends that consumers avoid sunscreens with oxybenzone. But there are also other chemical filters that show similar indications of hormone disruption or skin allergy. Two European studies have detected oxybenzone and other sunscreen filters in mothers’ milk, indicating that a developing fetus and newborns may be exposed to these substances (Schlumpf 2008, Schlumpf 2010). A 2010 study of Swiss mothers by Margaret Schlumpf of the University of Zurich found that at least one sunscreen chemical in 85 percent of milk samples. They have also been linked to lower sperm count and endometriosis in females.

Physical sunscreens, on the other hand, like zinc oxide and titanium dioxide, are made of natural elements found on the earth, and are said to “block” or “scatter” UV rays so they never penetrate the skin in the first place. Later research showed this wasn’t entirely true; physical sunscreens absorb UV rays as well, but they do retain some scattering ability, depending on the size of the UV wavelength. But, they also do not get absorbed by the skin. Mineral sunscreens usually rate better than chemical sunscreens for safety in the EWG database. In general, physical sunscreens are considered to be the safer options because they offer a more broad-spectrum protection, and lack the hormone-disrupting effects.


Shocking Results of the Mainstream Market Studies

It is well known now that your sunscreen may not deliver the sun protection factor or SPF that it promises on the label. For the last few years there have been many tests done on SPF on the market and the results are shocking.  In one study they tested and rated more than 60 lotions, sprays, and sticks with SPF claims of 30 or higher. (30 being the minimum level recommended by the American Academy of Dermatology). But 28 of these, a shocking 43 percent, failed to meet the SPF claim on the label! Three of them fell far short, with tests showing an SPF of less than 15. That’s not enough sun protection, and it could leave you vulnerable to sunburn and possible long-term skin damage, such as wrinkles or skin cancer.

Unfortunately those results aren’t just a fluke; this has been the same pattern shown in testing over the past few years. Of all the sunscreens that were tested over the last few years in similar studies have shown to fall far below the SPF number printed on the label so choose wisely. The Food and Drug Administration (FDA) doesn’t routinely test sunscreens; it requires the manufacturers to test their products. But in most cases the companies don’t have to submit their results, just keep them on hand in case the FDA asks to see them. So in short, they are simply not regulated like they should to be deemed safe.


The Safer Option - Physical Sunscreens

Zinc Oxide

Zinc Oxide is considered the safest option for sunscreen and the most widely used.  It is not water soluble so it has great lasting ability. Zinc Oxide also helps to calm inflammatory skin conditions like ulcers and wounds, warts, acne, rosacea, psoriasis, eczema, burns, scars, photo-induced aging, diaper rash and dandruff. Due to this, it is used in many different skin products for a million different reasons. In 2007 Researchers tested zinc oxide and found it offered broad-spectrum UV protection, and was “photo-stable,” meaning it didn’t alter in dangerous ways when exposed to UV rays, where chemical SPF do.

Titanium Dioxide

Titanium Dioxide is an earth mineral used as a thickening, whitening, lubricating, and sunscreen ingredient in cosmetics. It protects skin from UVA and UVB radiation and is considered to have no risk of skin irritation. Because of its gentleness, titanium dioxide is an excellent sunscreen active for use on sensitive or rosacea-affected skin. It’s also great for use around the eyes, as it is highly unlikely to cause stinging to sensitive skins. It was also found that micronized titanium dioxide does not penetrate the skin, so there is no need to be concerned about it getting into your body. Even when titanium dioxide nano-particles are used, the molecular size of the substance used to coat the nano-particles are large enough to prevent them from penetrating beyond the uppermost layers of skin. This means you’re getting the sun protection titanium dioxide provides, without any risk of it causing harm to skin cells. All-in-all, titanium dioxide is great broad-spectrum SPF ingredient. 

Though titanium dioxide works in a similar manner in providing broad-spectrum protection, its safety isn’t as well-documented as zinc’s. Zinc is the only active sunscreen ingredient approved by the FDA for infants under six month.  


My Favourite natural SPF Solutions For All Skin Types

Persimmons and Cantaloupe Day Cream SPF 32
Red Current Protective Moisturizer SPF 30
Eminence Tinted Moisturizer SPF 20
Bright Skin Moisturizer SPF 30
Tropical Vanilla Day Cream SPF 32
Tropical Vanilla Day Body Cream SPF 32
Eminence Sun Defense Minerals SPF 32
Jane Iredale Mineral Makeup SPF 20

All in all, keep you and your loved ones safe and healthy. Sunscreen is a part of a healthy long life, just make sure you are choosing the right one! Because as you now know, the wrong SPF can sometimes cause more harm then good! So choose wisely.


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