While virtually everyone is familiar with the damage sun can do to skin, few are aware of its effects on hair.
Sunlight comes in different wavelengths, with the most familiar being the ultraviolet rays UVA and UVB (there is actually a UVC ray as well, which is the strongest ultraviolet ray and can actually be fatal, but it is absorbed by the ozone layer and does not actually reach the earth's surface). Both UVA and UVB rays can cause damage to the hair and scalp if adequate protection is not taken.
UVA - aka, the "aging" ray. The UVA ray remains at the same strength all year round, regardless of the season; other than the UVC, this is the strongest ray and can penetrate deeply into the cortex. UVA rays can burn the cuticle of the hair, leading to porosity issues, and can damage melanin, the color pigment in our cortex responsible for our natural hair color. UVA rays can also sunburn the scalp and damage the hair follicles, leading to the risk of permanent hair loss over time.
UVB - aka, the "burning" ray. The UVB ray is the weakest strength ray and will have different strengths at different times of the year, depending on your location's proximity to the sun. This ray can still do some substantial damage to your hair, however; in addition to drying hair out, it can cause fadage in color-treated hair without protection.
So, if you live in an area where the sun's rays are strong, it is definitely not a bad idea to make sure your hair care products include a sunscreen or UV filter. The product ingredients you should look for on the label include:
- Benzophenone-2, ( or 3, 4, 5, 6, 7, 8, 9, 10)
- Benzyl salicylate
- Benzylidene camphor sulfonic acid
- Ethyl cinnamate
- Ethylhexyl methoxycinnamate (octyl methoxycinnamate)
- Octoxynol-40, -20
- Octyl methoxycinnamate
- Octyl Salicylate
- Phenyl ketone
- PEG-25 PABA
- Polyacrylamidomethyl benzylidene camphor
And, if all else fails, there is always a hat!