2013年4月28日星期日

Sunscreens Exposed: 9 Surprising Truths

Did you know that when you put on sunscreen, you are exposing yourself to chemicals that are 1000x more harmful than the sun?
from ewg.org

Sunscreens prevent sunburns, but beyond that simple fact surprisingly little is known about the safety and efficacy of these ubiquitous creams and sprays. EWG’s review of the latest research unearthed troubling facts that might tempt you to give up on sunscreens altogether. That’s not the right answer. Despite the unknowns about sunscreens’ efficacy, public health agencies still recommend using them, just not as your first line of defense against the sun. At EWG we use sunscreens, but we look for shade, wear protective clothing and avoid the noontime sun before we smear on the cream. Here are the surprising facts:


1. There’s no consensus that sunscreens prevent skin cancer.


The FDA’s 2011 sunscreen rules allow sunscreen makers to advertise that using their products can decrease the risk of skin cancer and sun-related skin aging. But a wide range of public health agencies – including the FDA – have found very little evidence that sunscreen prevents most types of skin cancer. In reviewing the evidence, the FDA said that the available clinical studies “do not demonstrate that even [broad spectrum products with SPF greater than 15] alone reduce the risk There’s no consensus that sunscreens prevent skin cancerof skin cancer and early skin aging.” The agency also said that it is “not aware of any studies examining the effect of sunscreen use on the development of melanoma.” The International Agency for Research on Cancer recommends clothing, hats and shade as primary barriers to UV radiation. It says that “sunscreens should not be the first choice for skin cancer prevention and should not be used as the sole agent for protection against the sun” (IARC 2001a). Read more.

2. There’s some evidence that sunscreens might increase the risk of the deadliest form of skin cancer for some people.


Some researchers have detected an increased risk of melanoma among sunscreen users. No one knows the cause, but scientists speculate that sunscreen users stay out in the sun longer and absorb more radiation overall, or that free radicals released as sunscreen chemicals break down in sunlight may play a role. One other hunch: Inferior sunscreens with poor UVA protection that have dominated the market for 30 years may have led to this surprising outcome. All major public health agencies still advise using sunscreens, but they also stress the importance of shade, clothing and timing. Read more.


3. There are dozens of high-SPF products — but no proof they’re better.


The FDA has proposed prohibiting the sale of sunscreens with SPF values higher than “50+.” The There are dozens of high-SPF products — but no proof they’re betteragency has written that values higher than 50 would be “misleading to the consumer,” given that there is an “absence of data demonstrating additional clinical benefit” (FDA 2011a), and that “there is no assurance that the specific values themselves are in fact truthful…” (FDA 2007). Scientists are also worried that high-SPF products may tempt people to stay in the sun too long, suppressing sunburns (a late, key warning of overexposure) while upping the risks of other kinds of skin damage.
Flouting the FDA’s proposed regulation, companies continue to sell high-SPF offerings in 2012. More than 1 in 7 products now lists SPF values higher than 50+, compared to only 1 in 8 in 2009, according to EWG’s analysis of more than 800 beach and sport sunscreens. Among the worst offenders are Walgreens and Aveeno brands. These manufacturers boast SPF values greater than 50+ on more than 40 percent of their sunscreens Read more.

4. Too little sun might be harmful, reducing the body’s vitamin D levels.


Sunshine serves a critical function in the body that sunscreen appears to inhibit — producing vitamin The main source of vitamin D in the body is sunshine, and the compound is enormously important to health – it strengthens bones and the immune system, reduces the risk of various cancers (including breast, colon, kidney and ovarian cancers) and regulates at least a thousand different genes governing virtually every tissue in the bodyD. The main source of vitamin D in the body is sunshine, and the compound is enormously important to health – it strengthens bones and the immune system, reduces the risk of various cancers (including breast, colon, kidney and ovarian cancers) and regulates at least a thousand different genes governing virtually every tissue in the body (Mead 2008). About one-fourth of Americans have borderline low levels of vitamin D, and 8 percent have a serious deficiency (CDC 2012). Particular groups are at the highest risk – breast-fed infants, people with darker skin and people who have limited sun exposure (NIH 2012).

Some people can make enough vitamin D from 10 to 15 minutes of unprotected sun exposure several times a week. But many others cannot. The right amount depends on the individual’s age, skin tone, the intensity of sunlight, time outdoors and skin cancer risk. Check with your doctor to see if you should get a vitamin D test or if you should take seasonal or year-round supplements.

5. The common sunscreen ingredient vitamin A may speed development of cancer.


Recently available data from an FDA study indicate that a form of vitamin A, retinyl palmitate, may speed the development of skin tumors and lesions when applied to skin in the presence of sunlight (NTP 2009). This evidence is troubling, because the sunscreen industry adds vitamin A to 25 percent of all sunscreens.

According to a report by AOL News, about half of the sunscreens tested contained vitamin A ingredients and derivatives like retinol and retinyl palmitate, which FDA's own studies have shown are photocarcinogenic, meaning they become toxic when exposed to sunlight. In fact, an older FDA report explains that sunscreens containing vitamin A ingredients cause tumors and lesions to develop and spread 21 percent faster than sunscreens that do not contain vitamin A ingredients.

The industry puts vitamin A in its formulations because it is an anti-oxidant that slows skin aging. That may be true for lotions and night creams used indoors, but the FDA recently conducted a the FDA recently conducted a study of vitamin A’s photocarcinogenic properties – the possibility that it can promote cancerous tumors when used on skin exposed to sunlight. study of vitamin A’s photocarcinogenic properties – the possibility that it can promote cancerous tumors when used on skin exposed to sunlight. Scientists have known for some time that vitamin A can spur excess skin growth (hyperplasia) and that in sunlight it can form free radicals that damage DNA.

In the FDA’s one-year study, tumors and lesions developed sooner in lab animals coated in a vitamin A-laced cream than animals treated with a vitamin-free cream. Both groups were exposed to the equivalent of just nine minutes of maximum intensity sunlight each day.
It’s an ironic twist for an industry already battling studies that have questioned whether their products protect against skin cancer. The FDA data are preliminary, but if they hold up in the final assessment, sunscreen makers have a big problem. In the meantime, EWG recommends that consumers avoid sunscreens with vitamin A (look for “retinyl palmitate” or “retinol” on the label).

6. Free radicals and other skin-damaging byproducts of sunscreens.


Both UV radiation and many common sunscreen ingredients generate free radicals that damage DNA and skin cells, accelerate skin aging and cause skin cancer. An effective sunscreen prevents more damage than it causes, but sunscreens are far better at preventing sunburn than at limiting free radical damage. While typical SPF ratings for sunburn protection range from 15 to 50, equivalent “free radical protection factors” come in at about 2. When consumers apply too little sunscreen or reapply it infrequently – and that’s more common than not – sunscreens can cause more free radical damage than UV rays on bare skin. The FDA could improve sunscreens’ ability to reduce free radical skin damage by strengthening standards for UVA protection.
According to Dr. Mercola, Oxybenzon and Retinyl Palmitate should be avoided:

Oxybenzone

Sixty-five percent of non-mineral sunscreens on the U.S. market contain oxybenzone. This chemical penetrates your skin in large amounts, potentially triggering allergic reactions. Oxybenzone is also a potential endocrine-disrupting chemical that can cause hormone disruption and cell damage.

It's been found that 97 percent of Americans are contaminated with oxybenzone, and researchers have specifically advised against using this chemical on children, who are especially vulnerable to endocrine-disrupting chemicals. Writing in the journal the Lancet, researchers noted:

"It would be prudent not to apply oxybenzone to large surface areas of skin for extended and repeated periods of time unless no alternative protection is available. There may be an additional concern for young children who have less well-developed processes of elimination and have a larger surface area per body weight than adults, with respect to systemic availability of a topically applied dose."

Vitamin A (Retinyl Palmitate)

The sunscreen industry uses vitamin A in its formulations because it is an anti-oxidant that is thought to slow skin aging. However, a U.S. Food and Drug Administration (FDA) study found that a form of vitamin A, retinyl palmitate, when used in sunscreen and therefore exposed to sunlight may actually speed the development of skin lesions and tumors.

This conclusion came from EWG's analysis of the findings released by the FDA and the National Toxicology Program. As EWG stated in the 2011 report:

"EWG analysis of product labels finds retinoid ingredients in hundreds of sunscreens, skin lotions, lip sticks and lip sunscreens—all of which pose safety concerns for sun-exposed skin. At this point, the NTP [National Toxicology Program] and FDA have invested more than a decade in studying retinoids, concluding in January 2011 that both retinyl palmitate and retinoic acid speed the development of cancerous lesions and tumors.

A year after EWG sounded the alarm about retinyl palmitate, there is still no FDA position on the safety of retinoids in cosmetics. Sunscreen industry trade groups continue to dispute EWG's warning. Most cosmetics companies have not removed these ingredients from sunscreens and other skin and lip products.

EWG recommends that consumers avoid products containing vitamin A, retinyl palmitate and retinol."

7. Pick your sunscreen: nanomaterials or potential hormone disrupters.


The ideal sunscreen would completely block the UV rays that cause sunburn, immune suppression and damaging free radicals. It would remain effective on the skin for several hours and not form harmful ingredients when degraded by UV light. It would smell and feel pleasant so that people use it in the right amount and frequency.

Unsurprisingly, there is currently no sunscreen that satisfies all these criteria. The major choice in the U.S. is between “chemical” sunscreens, which have inferior stability, penetrate the skin and may disrupt the body’s hormone systems, and “mineral” sunscreens (zinc and titanium), which often contain micronized- or nanoscale particles of those minerals.

After reviewing the evidence, EWG determined that mineral sunscreens have the best safety profile of today’s choices. They are stable in sunlight and do not appear to penetrate the skin. They offer UVA protection, which is sorely lacking in most of today’s sunscreen products. Mexoryl SX (ecamsule) is another good option, but it’s available in very few formulations. Tinosorb S and M could be great solutions but are not yet available in the United States. For consumers who don’t like mineral products, we recommend sunscreens with avobenzone (3 percent for the best UVA protection) and without the notorious hormone disrupter oxybenzone. Scientists have urged parents to avoid using oxybenzone on children due to penetration and toxicity concerns. Read more.

8. Europe’s better sunscreens.


Sunscreen makers and users in Europe have more options than in the United States. In Europe, sunscreen makers can select from among 27 chemicals for their formulations, compared to 17 in the U.S. Companies selling in Europe can add any of seven UVA filters to their product, but they have only three available for products marketed in the U.S. Sunscreen chemicals approved in Europe but not by the FDA provide up to five times more UVA protection; U.S. companies have been waiting five years for FDA approval to use the same compounds. Until the FDA approves these ingredients and lifts restrictions on combining certain active ingredients, strong UVA protection will be scarce in US sunscreens.

Top 5 Toxic Sunscreen Ingredients

The following is an excerpt from Top 5 Toxic Sunscreen Ingredients:

1. Oxybenzone a.k.a. benzophenone-3 is a chemical added to most sunscreens to guard the skin from UVA rays. It also prevents other sunscreen ingredients from deteriorating. Sunlight causes oxybenzone to form free radical chemicals linked to cell damage.

2. Nanoparticles are extremely tiny particles added to sunscreen because they are easily absorbed by the skin. “Spray Sunscreens” frequently contain nano particles and are more dangerous. This is because the particles can be inhaled. Safe metals such as zinc and titanium dioxide occurring in most sunscreens are safe as long as they aren’t put in nano particle form

3. Retinyl Palmitate [RP] received a lot of press a few years ago. I posted about this on Toxic Beauty Blog in June of 2010 and again a year later. RP is a form of vitamin A added to 41% of the sunscreens on the market and to other skin care products. In a National Toxicology Program (NTP) study, it was found when skin is treated with a mix of retinyl palmitate and skin cream and is exposed to ultraviolet light, the cream with retinyl palmitate stimulated lesion and tumor growth. While Vitamin A is a wonderful skin care ingredient when in it’s natural state, it obviously has no business being in a sunscreen when your skin is in direct sunlight.

4. Octyl methoxycinnamate, also known as Octinoxate, Eusolex 2292 and Uvinul MC80, creates free radicals inside the skin which post significant threat to DNA. Like oxybenzone, it works with other penetration enhancers to penetrate skin and accumulates in the body. Also, similarly to retinyl palmitate, it has phototoxic effects (toxic reaction provoked by light and often linked to photosensitivity!)

5. Another ingredient used to block UVA rays is Padimate O, paraminobenzoic acid, or PABA. According to the EWG’s Skin Deep database, “Research shows this chemical releases free radicals, damages DNA, has estrogenic activity, and causes allergic reactions in some people.” A report done by the FDA a few years ago implicated padimate O as a nitrosamine, a class of compounds known to be carcinogenic. Many people avoid this because it is irritating to the skin.

9. The FDA is still not protecting consumers.


In June 2011 the FDA announced new rules on labeling and effectiveness testing for sunscreens. They will ban the use of misleading claims like “sunblock,” “waterproof” and “sweatproof” and define which sunscreens can claim “broad spectrum” protection. FDA recently granted a 6 month delay in the implementation of these rules, until mid-December 2012. But even when implemented many gaps will remain.

The standard for UVA protection is weak and will allow nearly 90 percent of sunscreens to use the label “broad spectrum” without any reformulation. A weak standard gives companies no incentive to develop better, more effective sunscreens and masks major differences between products.

The FDA has not yet evaluated the efficacy and safety of new sunscreen ingredients or ingredient combinations. It has no plans to consider evidence of hormone disruption for sunscreen chemicals. The new rules still allow sunscreen makers to use ingredients such as vitamin A that can damage the skin in sunlight. They fail to require makers to measure sunscreen stability despite ample evidence that many products break down quickly in sunlight.

According to Dr. Leonard Caldwell, the sun actually prevents skin cancer! Caldwell stated, "Skin cancer, in my opinion, is only caused by the preservatives in the sunscreen."

See the video below!





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