Friday, March 23, 2007

Natural Sunscreens

The fact that we are experiencing some of the hottest weather on record made me think of a question I received earlier this year about natural sunscreens...specificially PABA. I took this as an opportunity to do a little research and here is what I found.

There are typically two types of sunscreens, chemical and physical. Chemical sunscreens are synthetic and provide protection from the sun by being absorbed into the skin. Chemical sunscreens feel lighter on the skin than physical sunscreens and generally have a higher SPF level than physical sunscreens. However, chemical sunscreens are typically more likely to irritate sensitive skin. Apply chemical sunscreens at least 20 minutes before heading outside since they need time to absorb into the skin.

Perhaps the best-known chemical sunscreen used for protection against UVA rays is avobenzone, or Parsol 1789. In 1997, the Food and Drug Administration approved Parsol 1789 for sunscreens. Parsol 1789 chemically alters the way sunlight enters your skin and there are no known dangers to using it . Broad spectrum protection is also provided by other synthetic ingredients such as benzophenone and oxybenzone, which protect by absorbing UV light. PABA (paraaminobenzoic acid) was once a popular UV-absorbing sunscreen ingredient, but it can cause skin irritation in some people and is now replaced by Padimate-O, a derivative of PABA. Other synthetic ingredients are octyl methoxycinnamate and menthyl anthranilate.

Physical sunscreens are the natural sunscreens that provide protection from the sun by sitting on top of the skin. They reflect or scatter ultraviolet light as it hits the skin forming a barrier between your skin and the sun. They start to work almost immediately after applying. The most common natural sunscreens are the natural minerals zinc oxide and titanium dioxide. These mineral compounds work by reflecting UVA rays and have long-standing safety records. Skin care experts debate which UVA blockers are most effective, but all of them work. One drawback to mineral-based ingredients is that they often show up white on your skin, but some transparent sunscreens now use them.

Antioxidants are often combined with titanium dioxide to slow down the oxidation of oils. Some popular natural antioxidants are vitamins E and C, rice bran oil (SPF 4), sesame seed oil (SPF 4), natural shea butter (SPF 6), and green tea (increases the sun protection activity of ingredients).

Recent research shows that green tea is indeed an effective sunscreen. A 1999 study published in the journal Photochemistry and Photobiology found that topical application of green tea may protect against the sun's UVB rays. This supports the findings of previous animal studies, which have also suggested that topical application of green tea may protect against the sun. The major polyphenolic constituent in green tea, epigallocatechin-3-gallate (EGCG), is probably responsible for green tea's protective effect.

Recent research also shows that antioxidant supplementation may protect our skin. A paper published in a recent issue of the American Journal of Clinical Nutrition found that supplementation with carotenoids (25 mg/day) and vitamin E (500 IU/day) "may be useful for diminishing sensitivity to ultraviolet light."

Click here for some natural sunscreen recipes.

Most sources recommend a minimum SPF 8 when going outside but the lower SPF of natural ingredients can be suitable for less intense sun exposure. Also be sure to wear sunglasses and a hat to further protect the eyes and face.


Marie Anne said...

Tracey, I'm glad you joined in the Z to A in May challenge! Everything starts on Monday (we don't post letters on Sunday), so you're not behind.

Susanne said...

I know exactly what you mean. I am a true Aroma lover and try to ensure everything I use daily is derived from natural ingredients.
I'm glad that my kids are growing up that way too.