Some websites say sunscreens in hair care only work if the product is wet, others disagree. To get the real scoop, we asked Matt Malek, a cosmetic chemist at Shiva Labs in Houston, Texas, who holds a master's degree in industrial chemistry, “Do sunscreens in hair care really work?”

Q: If sunscreens in hair care do work, why is there no SPF or rating system for them in hair care?
A: SPF and sunscreen terms are used for OTC products that are designed to prevent sunburn, cancer, wrinkles, etc. in skin products. Hair marketers use words like UV absorber, sun filter, sun protection or hair protection factor when using products like our Escalol HP. It works well at as low as 0.5% in a rinse-off conditioner.

Q: You measured this with a Hunter Lab Colorimeter. In lay terms, what’s that and what is it measuring?
A: The Hunter Lab Colorimeter is used by all hair color chemists. You can even buy a hand-held version from Minolta. This is an instrument that measures reflective colors from paper, fabric, hair, etc., so you can measure before and after.

Q: You’ve measured bond cleavage, combability and tryptophan degradation in hair, in relation to hair care sun protection ingredients. What is the role of tryptophan in hair?

A: Tryptophan is an amino acid that makes up part of the building blocks of protein, of which the hair is made. We can easily measure the decomposition of tryptophan when it is exposed to UV light or heat. It’s a marker that the hair protein/structure is being decomposed when people are in the sun or a UV environment. After International Specialty Products published in 1998—they’re recognized globally for innovative specialty products—other researchers published supportive results that indicate UVB damage occurs throughout the cuticle and cortex. Combination of UVB exposure and shampooing dramatically enhances the loss of color from hair.

Q: What’s on the horizon in hair UV protection?
A: Combinations with various organic and inorganic UV filters in specialized putties.