To D or Not to D?

Health

Getting enough calcium, iron, vitamin D and folate is important. But experts say more isn’t necessarily a good thing.

IN CREATING new food products, today’s manufacturers are in a fortifying frenzy. Everything from milk and cereal to frozen waffles and ice cream is pumped with 100 percent of the daily recommended value for select vitamins and minerals. And while fortification is responsible for virtually annihilating diseases like scurvy, experts worry that people are turning to souped-up foods to compensate for diets that are less than ideal.

There’s no combination of vitamins and minerals that can combat a terrible diet or not getting enough sleep. People who consistently eat a varied diet with plenty of fruits, vegetables, whole grains and lean meats may not even need a supplement.

“But for certain populations, or even those of us who rarely get our nutrients via home-cooked meals and fresh produce, fortified foods have been a godsend,” says Cheryl Rock, a professor in the Department of Family and Preventive Medicine at the University of California, San Diego.

Here’s a nutrient-by-nutrient guide on getting the most bang for your fortified food buck (these dietary reference intakes, or DRIs, are for adult, nonpregnant women):

CALCIUM (DRI 1,000 milligrams): Most of the calcium in our bodies is in our bones, and that’s the first place the body draws from when the mineral is needed for functions like keeping the heart beating regularly. Calcium plays an integral role in preventing chronic diseases such as osteoporosis, hypertension and heart disease, and it’s required for bone and tooth formation.

Pros: Many women fall short of calcium recommendations. “Your body can’t build bone without calcium,” says Rock. “Even if you’re exercising, your body still has to have something to work with. That’s where calcium comes in.” And with the increasing variety of calcium-fortified foods, meeting recommended intake levels is a snap—even for those who can’t tolerate dairy products.

Cons: The overwhelming prevalence of calcium-fortified foods makes it easy for people to exceed the National Academy of Sciences’ upper intake level of 2,500 milligrams per day. This can lead to nutrient imbalance, since excess calcium interferes with adequate absorption of competing nutrients such as iron, says Norma Flood, a La Jolla nutrition therapist. Too much calcium can also lead to kidney stones, calcium deposits and, ironically, weakened bones.

Should You Soup Up? If you’re on a high-protein diet (which increases loss of calcium from the bone), have a family history of osteoporosis or are training for a marathon, choosing calcium-fortified foods or supplements is a good idea—especially if you don’t eat dairy products. Just make sure the foods you pick are also fortified with vitamin D, which helps your body use calcium properly, says Rock.

VITAMIN D (DRI 400 International Units): Touted as super-nutrient of the decade, vitamin D is important for more than just maintaining bone health. Emerging evidence links the nutrient with the prevention of autoimmune diseases such as multiple sclerosis, rheumatoid arthritis and diabetes. Vitamin D also plays a role in fighting inflammation, which is implicated in heart disease and cancer.

Pros: Many of us are staying out of the sun for fear of wrinkles, sunspots and skin cancer. The result: a population that’s increasingly devoid of naturally occurring vitamin D. Some experts claim vitamin D deficiency is an unrecognized epidemic among women of childbearing age. Unless you down a lot of fish liver oil, it can be very difficult to get the recommended daily value of 400 IU of vitamin D through food alone. Just five to 10 minutes of sun time, two to three days per week, will give you the equivalent of 5,000 IU of vitamin D.

Cons: Since D is a hard-to-get dietary nutrient, which is also in high demand, experts claim there are few drawbacks to foods fortified with this nutrient. But excessive vitamin D can lead to calcium deposits in the blood, and soft tissues.

Should You Soup Up? “If you go outside every day, you should have adequate vitamin D,” says Rock. “But it can’t hurt to get more.” This is especially true for women who avoid the sun or have dark skin.

FOLATE (DRI 400 micrograms): Best known for its role in preventing neural tube defects, folic acid is required to metabolize important proteins, which are the building blocks for genetic material (think DNA and RNA). It’s integral to healthy cell division and tissue growth, as well as the production of red blood cells.

Pros: Folate is critical for the rapid cell multiplication that occurs during pregnancy, fostering the development of the brain, spinal cord and central nervous system. In 1998, the government required manufacturers to fortify certain grain and cereal products with folic acid—a mandate that has resulted in a 19 percent drop in neural tube defects. Studies show that folic acid may reduce the risk of heart disease, help your brain stay sharp as you age and ward off depression.

Cons: Americans are consuming more than twice as much folic acid as originally intended when the food fortification program began. “Fortification of unhealthy foods with folate, like processed sugar cereal, is not ideal,” says Flood. Better to load up on healthful leafy greens. While folic acid is not toxic, daily intake of more than 1,000 micrograms can mask anemia in a person with a vitamin B12 deficiency, which can lead to permanent nerve damage. The elderly are particularly vulnerable.

Should You Soup Up? It’s a good idea to boost your intake of folate during times of stress, injury, illness and recovery. Extra folate will help your body repair itself. If you stop using birth-control pills so you can become pregnant, get your folate levels checked before you try to conceive, since oral contraceptives may deplete folate levels. To reach your 400-microgram quota naturally, load up on deep-green leafy vegetables—spinach, kale, broccoli and asparagus—and whole-wheat products.

IRON (DRI 18 milligrams): Iron is required for all body functions. About 75 percent of the body’s iron is contained in red blood cells, which carry oxygen from the lungs to all of the body’s tissues. Low levels of iron can increase your susceptibility to infection and starve the body’s tissues of oxygen, causing symptoms like listlessness, fatigue and irritability. Low iron may also play a role in faulty attention spans.

Pros: Increased iron intake can be good for women who lose a lot of iron during their monthly cycle. What’s more, iron absorption can be tricky and depends on a variety of factors, including whether you eat meat, if you consume competing nutrients simultaneously or if you’re taking medication.

Cons: The risk of iron overload from food is low, especially for women, but some studies show that high blood levels of iron may be a risk factor for heart disease. Iron also competes with important minerals like zinc and copper for absorption in the body. Improving your iron status by using fortified foods could cause a zinc deficiency.

Should You Soup Up? Menstruating women are at the highest risk for iron deficiency. Studies show that as many as 30 percent of women are iron deficient. If you’re a vegetarian or prefer to avoid red meat, try foods like whole-grain cereals, soybeans, quinoa, lentils and other legumes, says Flood. Or go the no-fuss route by cooking with castiron pots and pans. Acidic foods leach iron from the pots during cooking, so you’ll boost your iron intake.

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