But if products don't work, they can't be sold, right? Wrong.
The U.S. Food and Drug Administration (FDA) doesn't approve cosmetics before they are sold. The agency is supposed to be policing product claims, says John Bailey, a biochemist and chief scientist at the industry-funded Personal Care Product Council. However, the products aren't a public health issue, and the "FDA will tolerate a certain amount of … puffery," says Bailey, a former head of the FDA's cosmetics office.
On the purely cosmetic level, regular makeup options, such as foundations and blushers, slightly fill wrinkles and reflect light in such a way as to make your skin look smoother.
Large pores may cause your makeup to appear uneven, but exfoliating can remove the dead surface cells that clog and thereby enlarge pores, Schultz explains on his website.
The skin's natural exfoliating process slows down with age, but there are many exfoliating peels, cleansers and scrubbing devices on the market. Products with alpha-hydroxy acid (AHA), such as glycolic AHA, can make your skin more sensitive to sunlight for up to a week after you stop using it, the FDA warns.
Whether a cream or lotion can help to reduce puffiness and dark circles under your eyes is an area of debate among dermatologists. But consumers have clear preferences.
Priscilla Gillett Parr, 57, of Seahurst, Wash., says the Olay Regenerist Anti-Aging Eye Roller is "absolutely wonderful for bags, sags and black circles."
For redness, try the anti-redness products that have a green tint, says Daihung Do, a dermatologist at Beth Israel Deaconess Medical Center. But if you have rosacea, see a dermatologist.
Tina Adler writes about health, science and the environment.