 I've talked about sunscreen and topical retinoids. What other skin-creen components have been shown to help with skin aging? While placebo-controlled trials are the standard in most medical research, they're still all too rare for cosmetic products. This raises advocacy questions. Many are left with simply buying hope in a jar, as well as safety concerns. Cosmetics to this day contain an array of toxic chemicals. Of the more than 12,000 synthetic chemicals used in cosmetics, fewer than 20% have been recognized as safe. Of course, this doesn't mean natural ingredients are necessarily harmless. Poison Ivy is as natural as you can get, but you wouldn't want to rub it on your face. However, there are some relatively safe natural options with varying degrees of efficacy. In contrast to retinoic acid, a form of vitamin A that can be irritating, topical niacinamide, also known as nicotinamide, is a form of vitamin B3 that is non-irritating and found to be effective. It's been described as one of the best-studied cosmaceutical ingredients for anti-aging. But it looks like there are only two placebo-controlled human studies, which gives you an idea of the state of cosmaceutical science. Skin photoaging is largely mediated by UV-induced free radical formation. One of the consequences of excess sun exposure is the oxidation of sugars and proteins in the skin into yellow-brown pigments that give aging skin a yellowing, sallow appearance. Since niacinamide is a precursor to two potent antioxidants, the hope is that this process could be interrupted, and indeed, the first published study was entitled Topical Niacinamide Reduces Yellowing, Wrinkling, Red Blotchiness, and Hyperpigmented Spots in Aging Facial Skin. It was a 12-week, double-blind, placebo-controlled, randomized clinical split-face study of middle-aged women. In a split-face study, each woman is her own control, rubbing the active formulation, in this case 5% niacinamide in moisturizer, on one side of her face, and the placebo, straight moisturizer, on the other half, though neither she nor the researchers know which side is which until the code is broken at the end. This controls her skin type and administration technique, and different people apply facial products differently, but participants often use the same hand for applying the creams to both sides, so unless specified that different gloves be worn or hands washed in between, there can be cross-contamination. Anyway, at the end of 12 weeks, there was a small 5% reduction in wrinkles and fine lines, and slowing the development of blotchiness, spots, and salinus. A subsequent publication noted an improvement in skin elasticity as well. The magnitude of these effects may only be one-third to one-fifth as good as redinoic acid, but there were no reports of excess skin irritation. But, used a 4% concentration, an application was limited to crow's feet wrinkles around the eyes. Significant reductions in wrinkles by both subjective and objective measures were noted by the end of the 8-week study. 64% of the niacinamide side eye wrinkles unwent moderate or market improvement compared to 0% on the placebo side eyes.