 What is the truth about over-the-counter anti-aging products, which constitute a billion-dollar industry? There is a psychological effect from spending more, wrote a team of dermatologists, but don't be seduced by fancy packaging and high prices. Many products advertise dramatic results that are frequently exaggerated and misleading and are rarely scientifically supported. An independent product testing institute questioned the efficacy of anti-aging creams generally finds that beneficial effects could only be picked up using sensitive instruments without becoming clinically or noticeably detectable. They suggest these products may not work any better than typical moisturizers. Cross-sectional studies of Chinese and British women found that those who regularly used facial moisturizers were guessed to be about two years younger than those of the same age who didn't. However, a third-larger Dutch study did not, and regardless, snapshot and time studies can never establish cause and effect. Studies on moisturizers are limited, but they can improve the appearance of dry skin, which can otherwise look discolored, flaky, and rough. Moisturizers can hydrate the skin and may reduce the appearance of fine lines by 15 to 20%, called the oldest trick in the cosmetic industry, but may not do anything to treat the underlying cause. Whether a facial foundation or night cream or anti-aging serum, the formulations of most skin products are basically a moisturizer combined with purported active ingredients for marketing appeal. Which ingredients are actually active anti-aging agents? I'll give you a hint. Up to 90% of visible aging of someone's face is due to sun exposure. From an anti-aging standpoint, the most biologically active ingredient in skin products is sunscreen. Consider the most important thing to maintain youthful skin is the daily application of sunscreen and other protective measures like wearing a hat. All other things you can do for your skin pale in comparison, especially for those with pale skin. To prevent skin cancer, the American Academy of Dermatology recommends sunscreen with a SPF of 30 or higher, but an SPF of 15 can prevent skin aging. How do we know? Because it's been put to the test. 900 adults were randomized to years of daily sunscreen use or to continue their own discretionary use. It was considered unethical to withhold protection by giving people placebo sunscreen. In the end, 77% of the recommended daily sunscreen group were applying sunscreen at least three to four days per week, compared with 33% in the discretionary use group. Would that be enough of a difference to make a difference? Yes, there was significantly less skin aging in the instructed daily use group. In fact, they suffered no detectable increase in skin aging over that 4.5-year study. The researchers concluded daily sunscreen use protects against skin aging. Although sunscreens are primarily intended to prevent further facial aging, rather than reverse photo damage already done, some in the daily sunscreen use group did show an improvement in skin texture. The results are all the more striking, given the control group was told to continue to use sunscreen and hats whenever they thought necessary, suggesting people are poor judges or planners for excess UV exposure when left to their own devices. So, a daily facial moisturizer with an SPF of 15, and it is recommended, even if it's cloudy or raining outside, considered the gold standard for anti-aging skincare, daily use of sunscreens in the daytime and retinoids at night. Retinoids? I'll cover them next.