Data from animal studies suggest that sunscreens prevent development of skin cancer, and that UVA protection may be as important as UVB protection in that respect . As noted earlier, energy in the UV wavelengths has also been shown to cause changes in the skin immune response. Moyal, who evaluated the level of protection by two broad-spectrum sunscreens with the same SPF, but with different UVA protection factors, against acute solar-simulated UV radiation-induced immunosuppression in humans, found that the sunscreen with the higher UVA protection factor was substantially more protective . Perhaps the most important reason for the need for high levels of UVA protection is that SPF is determined by using solar simulators that typically lack the relative levels of UVA power found in sunlight at most latitudes and may overestimate the degree of sun protection actually received . Calculations made by using solar spectra and sunscreen transmission spectra show that products providing high levels of UVA protection are more protective than products with similar labeled SPFs for the solar spectra most frequently encountered by consumers.
Increasing awareness of the need for skin protection against the UVA portion of the solar spectrum (320-400 nm) has accelerated development of sunscreen products that provide substantial UVA protection. Since these products have labeled SPF values similar to those of products that provide primarily UVB protection and relatively little UVA protection, there is a need for a reliable and informative index of UVA protection.
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Rosacea and Eczema are two skin conditions that are fairly commonly found throughout the world. Each of them is characterized by different features, and can be both discomfiting as well as result in undesirable appearance features. In a nutshell, theyre problems that many would want to deal with.