Apanhar sol atrás de um vidro traz benefícios? E malefícios?

Parece que o benefício da Vitamina D atrás de um vidro não existe (vidros comuns filtram o UV-B) é que continua a existir risco de cancro de pele (em excesso os UV-A fazem igualmente mal):
https://www.independent.co.uk/life-style/health-and-families/features/can-you-get-a-tan-and-absorb-vitamin-d-through-a-window-a6895626.html

Citando:
"The sun emits ultraviolet (UV) A, UVB, and UVC rays. The latter is the most damaging, but is filtered by the atmosphere and doesn’t reach the earth’s surface.

Vitamin D is produced by the body when the skin is hit by UVB rays, with 7-dehydrocholesterol being the resulting chemical. But most glass windows block this wavelength meaning you can't reap the health benefits.

(...)
A 2010 US study into skin cancer found that people who spend a lot of time driving a car each week are more likely to develop skin cancers on the left side of the body – which is the window side in North American cars.

Data on 1,000 patients showed that 74 per cent of patients with malignant melanoma, an aggressive form of skin cancer, had tumours on their left sides, according to the study by researchers at the St Louis University, the New York Times reported."

Link to news on this study;
http://www.nytimes.com/2011/04/05/health/05really.html

Novo composto protege contra UVA (mitoiron claw)

http://www.techtimes.com/articles/170872/20160722/new-sunscreen-compound-offers-cellular-level-protection-against-uva-rays.htm

Citando:
"Numerous sunscreens are available in the market today but most of them protect well only against UVB rays, leaving UVA protection limited. This is problematic because UVA rays penetrate deep into the skin, causing damage at the cellular level.

To address this issue, researchers have uncovered a compound that can be added to sunscreens that offers unexpectedly strong protection against UVA exposure, particularly within the cell where most of the damage related to UVA occurs.

Concentrations of free iron are highest within the mitochondria, the powerhouse of the cell. However, free iron turns into a catalyst for toxic reactive oxygen species when exposed to UVA, facilitating damage to cellular components that lead to increased risks of cancer and cell death.

The custom-designed iron chelator called mitoiron claw that the researchers developed attaches to iron atoms like a claw (hence its name), safely binding excess free iron and keeping them from reacting once exposed to UVA rays.

The researchers carried out tests involving human skin cells exposed to UVA at a rate equivalent to 140 minutes of uninterrupted sun exposure and saw that mitoiron claw-treated cells received complete protection against cell death."