Think supple skin and hair come in a bottle? You may be right—but not necessarily from the ones in your bathroom. Essential fatty acids (EFAs) are among the primary building blocks of beauty—from the inside. In fact, one of the first signs of an EFA deficiency may be dry skin or brittle tresses; and if you're like many Americans, you may not be getting enough. Taking extra EFAs, such as omega-3-rich fish or flaxseed oils, can be an excellent way to fortify your looks.

Boost your intake>> Aim to get 1 to 3 grams of omega-3 fatty acids daily from food and supplements. Fish contains approximately 1/2 to 1 gram per 3-ounce serving. Make up the rest with supplements.

Not all oils are created equal>> Choose fish oil products that are independently certified free of heavy metals or PCBs (polychlorinated biphenyls). Opt for flaxseed oil that is genetically modified organism-free (GMO-free).

Keep your supply cold>> Essential fats are very fragile—heat, light, or oxygen can rapidly degrade them—so store them in the refrigerator.