Since we're now featuring non-nano, uncoated Zinc in our ELEMENTAL DAY SILK composition, I thought I'd weight in on the mineral sunscreen/non-nano/uncoated/SPF etc discussion, and offer my wholesome perspective on the topic.
NON-NANO VERSUS NANO ZINC
While there are numerous scientific papers out there claiming nano particles of zinc oxide used in invisible Zinc sunscreens do not get absorbed into via the skin, don't enter the bloodstream and are supposedly not a threat to human health unless inhaled from spray or powder, nano particles of zinc oxide and titanium dioxide washed into waterways from our skin have a devastating effect on marine life.
Once the nanoparticles are suspended in water, they influence temperature, salinity and PH of our oceans, find their way into the food chain, deposit in sediment, infiltrate micro plankton and react with sunlight to create cell damaging oxidative stress in sensitive marine organisms. Personally, I'd rather go white face than trash our oceans by wearing invisible Zinc.
ZINC AND PHOTO REACTIVITY
Speaking of UV light: Zinc oxide, nano or not, shows minor photo-reactivity as it absorbs UVA/UVB. Because non-nano Zinc – as opposed to the blood-brain barrier piercing nano particle Zinc – sits on the dead outer layer of the skin, this process does not effect the living cells below, and compared to the astoundingly government approved active ingredients in chemical sunscreen or Titanium oxide, the rate of reactivity is very low.
Still, this is where we call on the naturally powerful antioxidant properties of seed oils, fruit oils and whole botanical extracts to balance and fortify the skin's natural defence. In my opinion, these are the real next level heroes in any natural sunscreen. Their complex composition of antioxidants such as vitamins (vitamin C, vitamin E in particular), flavonoids, and phenolic acids absorb, resist and block UVA/UVB rays without side effects and play first chair in fighting free radicals that can cause sunburn, wrinkles, lower immunity, premature aging and cancer.
UNCOATED VERSUS COATED ZINC
Lastly, a quick word on uncoated versus coated Zinc: Many sunscreens include zinc oxide particles coated with an inert substance usually lessen reactivity to sun exposure (see above), and to make them easier to mix with the other ingredients. This is, again, a personal choice for me. I don't go anywhere near anything coated with an 'inert substance' – meaning, like plastic, it does not biodegrade – especially when that substance is Dimethicone, a lab made silicon oil popular in non-natural skincare and shampoos and loved by trash cosmetic manufacturers because it makes products easily spreadable and fills in the fine lines and wrinkles on the face.
Although FDA approved, there's not a good thing about a plastic layer sitting on your skin:
- It traps everything under it: bacteria, sebum, impurities which causes breakouts, inflammation and and blackheads.
- The coating prevents the skin from breathing and performing its normal activities: sweating, temperature regulating, sloughing off dead skin cells, etc.
- Dimethicone is listed as a possible skin and eye irritant and prolonged exposure to dimethicone increases skin irritation.
- Those with sensitive or reactive skin are at risk of an allergic reaction to Dimethicone
- Dimethicone is a non-biodegradable chemical.
So no thanks, I'll have my Zinc uncoated and my skin independent, strong, healthy and natural.