Quick: Did you get enough vitamin E today? Even if you're diligent about your diet, you're likely to fall short on this and four other critical nutrients, according to recent USDA figures on the average amounts most midlife women consume. Here is where you may fall short.

Vitamin E

You Need: 15 mg/day

Why: This powerful antioxidant protects your cells, helps them to communicate with each other, and defends your skin against UV damage. If you don't get enough vitamin E, you may have problems absorbing other nutrients.

Potassium

You Need: 4,700 mg/day

Why: This electrolyte keeps your nervous system humming and your muscles toned. It also helps keep your blood pressure at normal levels. If you don't get enough, you may feel irritable, weak, and fatigued.

Calcium

You Need: 1,000-1,200 mg/day

Why: This mighty mineral builds strong bones, and that means a lower risk of osteoporosis for you. And in a study of nearly 84,000 women by Tufts-New England Medical Center, scientists found that those who consumed at least 1,200 mg of calcium daily (along with at least 800 IU of vitamin D, which helps absorption of the mineral) had a 33% lower risk of developing type 2 diabetes.

Vitamin A

You Need: 700 mcg/day

Why: This nutrient powers your eyesight, especially your night vision, and keeps your skin, gums, and teeth healthy. It also boosts your immune system and helps you fight off viruses. The older you get, the more you seem to require it to protect cognitive function.

Magnesium

You Need: 320 mg/day

Why: Magnesium is used in hundreds of chemical activities in the body, ranging from storing energy to helping your genes function properly. It keeps your nerves and muscles toned, your bones strong, and your blood circulating steadily. This mineral is so influential that women who got at least the recommended amount cut their risk of metabolic syndrome by 38% or more, reported a study by the CDC.