If you consistently eat a balanced, whole foods–based diet, do you really need to take supplements? If you’re aiming for optimal health as you age, the answer is yes. Beyond a high-quality multivitamin, which many experts recommend as a sort of nutritional health insurance, a handful of supplements help fill in important gaps. “Americans are often eating a lot but not getting enough,” says Robert Bonakdar, MD, of the Scripps Center for Integrative Medicine and editor of The H.E.R.B.A.L. Guide (Lippincott Williams & Wilkins, 2010). Shortfalls in essential nutrients tend to increase inflammation in the body, a state that is linked to a number of diseases, Bonakdar says. So what are the top supplements to add to your routine? Here are our experts’ picks.

Vitamin D

Deficiency in vitamin D, estimated to affect more than 70 percent of Americans, can increase your risk of mortality from many causes, including heart disease and cancer. Why? Vitamin D plays a crucial role in the body's ability to fight disease: A recent study found that vitamin D helps activate "killer" T cells. It's also critical for bone health. Concerns about skin cancer risk have contributed to deficiency because we block D-promoting rays with sunscreen, says Carolyn Dean, MD, ND, author of The Miracle of Magnesium (Ballantine, 2007).

Best form>> Take D3 (cholecalciferol), the more absorbable form made naturally by your skin. Vegans should opt for the D2 form; D3 is usually derived from lanolin, the oil in sheep’s wool.

Dose>> Up to 2,000 IU daily, or more if recommended by your health care provider after blood testing.

How to take>> Vitamin D is fat soluble, so take it with foods that contain fat.

Omega-3s

These healthy essential fatty acids support brain function and tame inflammation in the body. Supplementing daily with at least 1,000 mg of omega-3 EFAs may help prevent heart attacks, says Bonakdar. EFAs also may help slow aging; a recent study found that people with the highest blood levels of omega-3s had the least chromosome damage, a marker for aging and age-related disease. By improving brain-receptor function, omega-3s help protect the brain from stress, says Charles Moss, MD, founder of the La Jolla Clinic of Integrative Medicine in California.

Best form>> Fish oil. Omega-3s such as alpha-linolenic acid (ALA) in flaxseed and other plant-based sources are beneficial, but experts put fish oil first because of its brain-supporting docosahexaenoic acid (DHA). Buy high-quality, certified Good Manufacturing Practice (GMP) products and look for labels that assure contents have passed testing for mercury, arsenic, lead, and PCBs.

Dose>> 320–1,000 mg of eicosapentaenoic acid (EPA) daily and about two-thirds as much DHA, says Moss. Don’t take higher doses if you take blood thinners or high doses of aspirin, or are anticipating surgery.

How to take>> Pair with a multivitamin that includes antioxidant vitamins C (500 mg) and E (200 IU; mixed tocopherols) and selenium (100–200 mcg); fish oil can oxidize, creating free radicals in the body. Store in the refrigerator to keep oil fresh.

Magnesium

Americans get significantly less of this mineral through foods than they did 100 years ago, partly due to soil-nutrient depletion. Some gastrointestinal diseases, diabetes, and prolonged stress also may cause deficiency. Your body requires magnesium to absorb calcium, so it’s crucial to bone health. Also essential for muscles and nerves, heart health, and metabolism, magnesium may decrease heart attack risk in older men, says Joe Pizzorno, ND, editor in chief of Integrative Medicine.

Best form>> Magnesium citrate or malate

Dose>> Experts generally recommend a 2:1 ratio of calcium to magnesium, or about 1,200 mg calcium for people older than 50 and 1,000 mg for those younger than 50, with half as much magnesium.

How to take>> Take 300 mg magnesium and 500 mg calcium (calcium citrate) together, twice daily. (Your body can only absorb about 500 mg calcium at a time.) If you experience loose stools, reduce the magnesium dose.

Coenzyme Q10

CoQ10 helps produce energy in the mitochondria of cells. Because the heart is one-third mitochondria, coQ10 is particularly crucial for heart health. As you age, your body naturally makes less coQ10, so supplements are vital after age 50 (and useful before then) for supporting cardiac performance, says Chris D. Meletis, ND, executive director of the Institute for Healthy Aging. What’s more, cholesterol-lowering statin drugs may decrease the body’s coQ10 levels. According to Bonakdar, people who suffer from headaches may also be coQ10 deficient.

Best form>> CoQ10 supplements are difficult for the body to absorb; look on labels for “certified GMP,” which indicates products are safe, pure, and effective.

Dose>> 50–100 mg daily; adults on statin drugs can take 200 mg or more daily.

How to take>> Take with a meal containing fat. Also, a recent study found taking coQ10 with grapefruit juice 

Curcumin

A powerful antioxidant extracted from the curry spice turmeric, curcumin boasts natural antibiotic abilities and powerful anti-inflammatory and anti-arthritic effects, says Rountree. It also protects against heart disease, may help prevent several cancers, and reduces the risk of neurodegenerative diseases such as Alzheimer’s, he says. It may reduce the production of pain-causing chemicals in the body, too.

Best form>> Look for combination curcumin-piperine. Derived from black pepper, piperine increases curcumin absorption by 2,000 percent, says Rountree.

Dose>> 750 mg curcumin and 2–5 mg piperine.

How to take>> Take with a meal.