If you have sensitive skin, look for moisturizers labeled "fragrance free" or "without perfume." Fragrances are the ingredients most likely to cause an allergic reaction, and even unscented products can contain fragrances that mask chemical scents [source: WebMD].
Whether you want to fight wrinkles, fade stretch marks or fake a sun-kissed glow, there's a moisturizer for you. One of the most common specialized moisturizers is anti-aging cream. Anti-aging creams typically contain collagen and elastin, which are proteins that help keep your skin toned and flexible [source: Mayo Clinic]. While these products may temporarily plump up wrinkles, topical creams can't replace the collagen and elastin from your skin's deeper layers.
Other ingredients designed to help smooth out wrinkles include alpha-hydroxy acids, retinoids, vitamin C, copper peptides and coenzyme Q10. Alpha-hydroxy acids help lift the top layer of dead skin cells to reduce the appearance of fine lines, and these acids may also stimulate collagen production. Retinoids reduce wrinkles and repair sun damage, and vitamin C can increase collagen production and protect skin from UV rays [source: Bouchez]. Copper peptides stimulate collagen production, and coenzyme Q10 reduces fine lines and provides protection from sun damage [source: Mayo Clinic].
Many of these anti-aging ingredients can also be found in toning and firming lotions. Coenzyme Q10 is used to improve skin's texture and reduce cellulite, and studies show that copper peptides smooth and firm skin [source: Cleveland Clinic]. Lotions that contain dimethylaminoethanol can also help firm skin and fight wrinkles by fighting free radicals and lifting sagging skin [source: Schwartz].
Although there are over-the-counter moisturizers that claim to get rid of stretch marks, doctors say they're not particularly effective [source: WebMD]. However, some research shows that creams containing tretinoin, an acid that rebuilds collagen, may improve the appearance of stretch marks that are less than six weeks old and still pink in color [source: Mayo Clinic]. If you're serious about banishing your stretch marks, you may want to look into stronger treatments like dermabrasion, chemical peels and laser treatment -- but always talk to your doctor first.
If you're looking to get a summer glow without exposing yourself to the sun's harmful UV rays, there are also skin-darkening moisturizers. These lotions give skin just a hint of color with the first use, and the color increases gradually with each application. The active ingredient usually found in these moisturizers is dihydroxyacetone, also known as DHA. It's a colorless chemical that produces a brown tone when it reacts with amino acids on the outermost layer of the skin [source: Mann]. Because skin is constantly shedding dead cells on the skin's surface, the color lasts about five days. Erythrulose is a skin-darkening ingredient that's often used as an alternative to DHA -- DHA can give skin an orange tint -- but DHA is the only FDA-approved sunless tanning ingredient. [source: Mayo Clinic].
Check out the links on the following page for more information on skin moisturizers.