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Scary Things You Didn't Know About Your Sunscreen

5 must-read facts about sunscreen ingredients, melanoma dangers and the sun's aging effects

Besides French pedis and sperm brows, one of the things beauty editors like to get all preachy about is sunscreen. As in they want you to wear some (and re-apply it) all day long, all year-round.

This post won't be quite like that.

While I do agree that sun exposure can be aging—and I don't even like the look of a tan anymore—the ins and outs of sunscreen are a bit trickier than just applying whatever UV-blocker's on the store shelf.

Many of us have already hopped on the mineral (as opposed to chemical) sunscreen bandwagon, but I recently came across some intel that I found really scary and surprising. Via the excellent Functional Performance Systems health blog, these facts are from Dr. Ray Peat's June 1996 newsletter (!!), and still HIGHLY relevant today.

UPDATE:See here for my top safe sunscreen recommendations!

1. Chemical sunscreens can actually increase the risk of melanoma.

What the what?

Well, first of all—know that this is how chemical sunscreens work, by being absorbed into the bloodstream. Unlike physical blocks, which sit on top of the skin, chemical SPFs soak in and "scatter all over the body without being detoxified by the liver." According to this Dr. Oz article, they "can be detected in blood, urine, and breast milk for up to two days after a single application."

As if that's not worrisome enough, there's this:

"...[C]hemicals used in the sun screen lotions, such as PABA derivatives... react dangerously with light, and are easily absorbed in significant quantities into the deeper layers of the skin, where they can cause mutations," says Ray Peat.

"For example, several recent studies have found that the sun-blockers, which decrease the ordinary skin damage caused by ultraviolet rays, actually increase the risk of developing melanoma, by causing mutations when the cells’ chromosomes interact with the sunscreen and the light. (Something similar happens in the disease, porphyria. A pigment that accumulates causes the skin to become very sensitive to the sun. Estrogen is known to intensify the disease.)

"...[S]o far, there is no research that shows any of the chemical ultraviolet blockers is safe."

That's a pretty damning conclusion, and one that the Dr. Oz people agree with (albeit years after Ray Peat said it first).

2. Titanium dioxide particles can become toxic when exposed to UV light.

So if chemical sunscreen isn't safe, you'll just switch to a mineral sunblock instead—right?

Zinc oxide and titanium dioxide are the two ingredients (derived from ground-down rocks) that do a good job of blocking UVA and UVB light. "If a sunscreen lotion is based on the use of an opaque reflective material, such as zinc oxide or titanium oxide, that substance remains mostly on the surface of the skin," says Ray Peat. "This should make it fairly harmless..."

Except there's a little catch. "...[I]t is possible that traces of titanium could be absorbed with oils into the skin, where it could be made toxic by interaction with ultraviolet rays."

Heard of a little problem called nanoparticles? They're becoming increasingly common in mineral-based sunscreens (as well as other beauty products) because the teensy-tiny sizes don't impart the characteristic white pigment that titanium dioxide is known for.

It's best to avoid sunscreens made with nano titanium particles, because they're not only "potential sources of serious inflammatory reactions," but also interact with the light and cause serious stress on the body. The Environmental Working Group has some more info here about nanotechnology in sunscreens, and suggests that zinc oxide is the best choice for sun protection.

My choice: CyberDerm's Simply Zinc (see here for review!).

3. Eating polyunsaturated oils accelerates the sun's aging effects.

The Skincare Edit Recommends

Imma repeat here what I said in my great big article about the dangers of polyunsaturated fats (PUFAs). It is consumption of them combined with sun exposure—and not just the sun on its own—that is the REAL culprit behind skin aging.

According to Ray Peat: "[The aging effect of the sun] is variable, and depends on our hormones and diet. The unsaturated oils have been identified as a major factor in skin aging."

"For example, two groups of rabbits were fed diets containing either corn oil or coconut oil, and their backs were shaved, so sunlight could fall directly onto their skin. The animals that ate corn oil developed prematurely wrinkled skin, while the animals that ate coconut oil didn’t show any harm from the sun exposure.

"In a study at the University of California,photographs of two groups of people were selected, pairing people of the same age, one who had eaten an unsaturated fat rich diet, the other who had eaten a diet low in unsaturated fats. A panel of judges was asked to sort them by their apparent ages, and the subjects who consumed larger amounts of the unsaturated oils were consistently judged to be older than those who ate less, showing the same age-accelerating effects of the unsaturated oils that were demonstrated by the rabbit experiments.

"While it is important to avoid overexposure to ultraviolet light, the skin damage that we identify with aging is largely a product of our diet."

Scary stuff, yes? So you'd be wise to reduce PUFAs in your diet (replacing them with coconut oil instead) on top of practising smart sun safety. More information about PUFA oils here.

4. Coconut oil, vitamin E and aspirin all have a sun-protective effect.

In addition to protecting your skin with reflective zinc oxide or titanium dioxide sunscreens, Ray Peat has this suggestion:

"Coconut oil has been used for generations in 'suntan lotions,' and whether it is absorbed through the skin or eaten as a food, it clearly has a protective antioxidant function.

"The old formula for suntan oil, coconut oil with iodine, might turn out to be a safe sunscreen, since the brown iodine absorbs light, as other 'U.V. blockers' do, but iodine is also an effective chain breaker that inactivates free radicals, and it can’t be absorbed into cells in its brown form. It doesn’t have the potential for causing cancer that the popular sunscreens do.

Consider vitamin E and aspirin too, especially if you get a sunburn:

"Vitamin E, taken internally or even applied to the skin, has been found to reduce the damage produced by exposure to ultraviolet radiation, which is logical, since it interrupts the chain reactions of toxic free-radicals produced when unsaturated oils are oxidized by radiation or other injury. Aspirin has been found to have a similar effect in reducing the harmful effects which develop in the skin after sunlight overexposure.

"Vitamin E and aspirin reduce the harmful effects of sunburn, even when used after exposure to the sun, they can be applied topically to the burned skin. Vitamin E often contains some soy oil, so I recommend small doses of about 100 ma. per day."

5. You can get the beneficial effects of sunlight with short bursts of exposure.

So how do you reap the beneficial effects of the sun—which include improved immune function, better moods, higher intelligence and faster metabolism, according to Ray Peat—without the harmful side effects?

Think about having frequent short bursts of bright light exposure, instead of lying outside for hours. Oh, and wear light, white clothes as often as possible.

"Frequent short exposures to bright light is almost as valuable as continuous sunlight, and it is less likely to cause skin aging," says Ray Peat. " Expose as much skin as possible to the bright light; even a minute is better than nothing. Thin, light-colored clothing transmits a considerable amount of light."

Even if you can't get outside, you can buy safe artificial lights to get similar benefits indoors:

"If artificial light is bright enough, it is as effective as sunlight at stopping the stress reaction, but people seldom use lights that are bright enough... A few seconds’ exposure to the direct light of ten 150 Watt incandescent bulbs, for just a few minutes every two or three hours, might provide more effective protection than continuous exposure to a single 100 Watt light."

Personally, when I can't get enough time outside, I use two of these brooder lamps with 120V heat lamp bulbs. Toasty! And I can most definitely attest to the resulting mood and metabolic boost.

Let me know what you think of these sun tips, and then go check out my favourite sunscreen product picks next!

Do you use chemical or physical sunscreen?

Are you worried about the nano issue?

Are you surprised that PUFAs accelerate aging?

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