Five years after telling a bunch of angry apes to keep their filthy paws off him, Charlton Heston starred in Soylent Green. In the film, a megacorporation solves a starving world’s need for nutritious food by turning the dead into dinner. This is complete science fiction, of course: Most of us are so short on key nutrients we couldn’t possibly be someone’s square meal.
In fact, studies show that 77 percent of men don’t take in enough magnesium, that many of us are deficient in vitamin D, and that the vitamin B12 in our diets may be undermined by a common heartburn medication. And we haven’t even mentioned our problems with potassium and iodine.
It’s time to play catch-up. Follow our advice, and a cannibal will never call you junk food.
This vitamin’s biggest claim to fame is its role in strengthening your skeleton. But vitamin D isn’t a one-trick nutrient: A study in Circulation found that people deficient in D were up to 80 percent more likely to suffer a heart attack or stroke. The reason? D may reduce inflammation in your arteries.
The shortfall: Vitamin D is created in your body when the sun’s ultraviolet B rays penetrate your skin. Problem is, the vitamin D you stockpile during sunnier months is often depleted by winter, especially if you live in the northern half of the United States, where UVB rays are less intense from November through February. Case in point: When Boston University researchers measured the vitamin D status of young adults at the end of winter, 36 percent of them were found to be deficient.
Hit the mark: First, ask your doctor to test your blood levels of 25-hydroxyvitamin D. “You need to be above 30 nanograms per milliliter,” says Michael Holick, M.D., Ph.D., a professor of medicine at Boston University. Come up short? Take 1,400 IU of vitamin D daily from a supplement and a multivitamin. That’s about seven times the recommended daily intake for men, but it takes that much to boost blood levels of D, says Dr. Holick.
This lightweight mineral is a tireless multitasker: It’s involved in more than 300 bodily processes. Plus, a study in the Journal of the American College of Nutrition found that low levels of magnesium may increase your blood levels of C-reactive protein, a key marker of heart disease.
The shortfall: Nutrition surveys reveal that men consume only about 80 percent of the recommended 400 milligrams (mg) of magnesium a day. “We’re just barely getting by,” says Dana King, M.D., a professor of family medicine at the Medical University of South Carolina. “Without enough magnesium, every cell in your body has to struggle to generate energy.”
Hit the mark: Fortify your diet with more magnesium-rich foods, such as halibut and navy beans. Then hit the supplement aisle: Few men can reach 400 mg through diet alone, so Dr. King recommends ingesting some insurance in the form of a 250 mg supplement. One caveat: Scrutinize the ingredients list. You want a product that uses magnesium citrate, the form best absorbed by your body.
Consider B12 the guardian of your gray matter: In a British study, older people with the lowest levels of B12 lost brain volume at a faster rate over a span of 5 years than those with the highest levels.
The shortfall: Even though most men do consume the daily quota of 2.4 micrograms, the stats don’t tell the whole story. “We’re seeing an increase in B12 deficiencies due to interactions with medications,” says Katherine Tucker, Ph.D., director of a USDA program at Tufts University. The culprits: acid-blocking drugs, such as Prilosec, and the diabetes medication metformin.
Hit the mark: You’ll find B12 in lamb and salmon, but the most accessible source may be fortified cereals. That’s because the B12 in meat is bound to proteins, and your stomach must produce acid to release and absorb it. Eat a bowl of 100 percent B12-boosted cereal and milk every morning and you’ll be covered, even if you take the occasional acid-blocking med. However, if you pop Prilosec on a regular basis or are on metformin, talk to your doctor about tracking your B12 levels and possibly taking an additional supplement.
Without this essential mineral, your heart couldn’t beat, your muscles wouldn’t contract, and your brain couldn’t comprehend this sentence. Why? Potassium helps your cells use glucose for energy.
The shortfall: Despite potassium’s can’t-live-without-it importance, nutrition surveys indicate that young men consume just 60 percent to 70 percent of the recommended 4,700 mg a day. To make matters worse, most guys load up on sodium: High sodium can boost blood pressure, while normal potassium levels work to lower it, says Lydia A. L. Bazzano, M.D., Ph.D., an assistant professor of epidemiology at Tulane University.
Hit the mark: Half an avocado contains nearly 500 mg potassium, while one banana boasts roughly 400 mg. Not a fan of either fruit? Pick up some potatoes—a single large spud is packed with 1,600 mg.
Your thyroid gland requires iodine to produce the hormones T3 and T4, both of which help control how efficiently you burn calories. That means insufficient iodine may cause you to gain weight and feel fatigued.
The shortfall: Since iodized salt is an important source of the element, you might assume you’re swimming in the stuff. But when University of Texas at Arlington researchers tested 88 samples of table salt, they found that half contained less than the FDA-recommended amount of iodine. And you’re not making up the difference with all the salt hiding in processed foods—U.S. manufacturers aren’t required to use iodized salt. The result is that we’ve been sliding toward iodine deficiency since the 1970s.
Hit the mark: Sprinkling more salt on top of an already sodium-packed diet isn’t a great idea, but iodine can also be found in a nearly sodium-free source: milk. Animal feed is fortified with the element, meaning it travels from cows to your cereal bowl. Not a milk man? Eat at least one serving of eggs or yogurt a day; both are good sources of iodine.