ABSTRACT
Observable Cutaneous Effects of Sun Exposure 45
Production of Vitamin D 46
Tanning 46
Sunburn 46
Skin Cancer 46
Photoaging 47
Sunscreen Use and the Sun Protection Factor 47
How Large Should the SPF Be to Prevent Sunburn? 48
How High Should the SPF Be to Give a Worthwhile Reduction in
Lifetime Risk of Skin Cancer? 49
Is Daily Use of Sunscreens of Benefit? 50
A Strategy for Sunscreen Use 51
References 52
OBSERVABLE CUTANEOUS EFFECTS OF SUN EXPOSURE
Ultraviolet (UV) radiation exhibits a number of effects on skin, both beneficial
and undesirable. The purpose of sun protection should be to minimize the
likelihood of adverse effects without undue detriment to the beneficial effects.
The biological effects of UV on skin are summarized below.
