At first glance, it may appear fortified foods offer more nutrition for your dollar, but some experts warn that the added vitamins and minerals often aren't needed, and too much of a good thing increases risk of harm. Fortification also may trick you into viewing something as a better choice when it's really not.
SPOTTING MARKETING HYPE
What began as a thoughtful practice to correct common deficiencies or replace nutrients lost during food processing seems to have evolved into a "willy-nilly, nutrient-of-the-day" approach, says Mara Vitolins, Dr.PH., R.D., co-author of a July 2014 article on fortification in Critical Reviews in Food Science and Nutrition.
"For example, adding folic acid to bread and other grain products to help prevent neural tube birth defects makes sense, but adding 100 percent of a dozen vitamins and minerals to a single bowl of cereal is unnecessary," Vitolins says.
Pass up packaged foods that promote the vitamins and minerals inside, yet have sugar as one of the first few ingredients, Katz advises.
"Instead, opt for foods that have nutritional value to begin with, such as dairy products that may be enhanced by adding nutrients that tend to be deficient in the American diet, such as vitamin D," Katz says.
BALANCE, VARIETY, AND MODERATION
"When you take in excess nutrients, your liver has to process the surplus so the body can get rid of it," Vitolins says. An over-supply of water-soluble vitamins, such as the B vitamins and vitamin C, is disposed of in the urine. Even so, short-term symptoms, such as rashes and nausea linked with excess niacin (vitamin B3), are of concern.
An over-supply of fat-soluble vitamins, such as vitamins A and D, is stored in the body, so toxicity risk is greater. Nutrient imbalances also are possible. For example, too much zinc can interfere with absorption of copper and iron.
According to a June 2014 Environmental Working Group (EWG) report, young kids are especially at risk of getting potentially harmful amounts of vitamin A, zinc, and niacin, which is in part due to excessive food fortification and nutrition labeling largely focused on adults. The EWG advises passing on foods with more than 20-25 percent of the daily value of these three nutrients when feeding children.
Vitolins urges consumers to ask their doctor about lab testing to help determine whether they might be falling short of a nutrient, such as vitamin D or iron, rather than guessing.
"Some women need supplemental iron because they menstruate, but a man typically doesn't need extra iron. Men are generally better off passing up iron-fortified cereal," she says. "At the very least, if you buy a highly fortified food such as cereal, vary your intake with other choices during the week. Don't take a high dose supplement for nutrients you're already consuming in fortified foods."
Be aware that fortified, packaged foods also can squeeze out naturally nutrient-rich vegetables, fruits, beans, nuts, and whole grains.
"These foods have thousands of nutrient compounds in them, many of which haven't even been named yet, but that may have important health benefits," Katz says. "These nutrients also may work in concert with one another, providing greater benefits together than alone."
Beyond risks of imbalances and excesses, some people are concerned about the sources of nutrients used in fortification. Vitamins are often derived from genetically modified organisms (GMOs), a hotly debated practice wherein genes from different species are mixed in ways not possible with traditional cross-breeding.
"Vitamin E is frequently derived from soy and vitamin C from corn, which are commonly genetically modified crops," says Gwendolyn Wyard, regulatory director of organic standards and food safety at theOrganic Trade Association. "Additionally, vitamins B2 and B12 are now primarily produced by genetically engineered microorganisms such as bacteria. Some beta carotene (a vitamin A precursor) and vitamin C is made this way, too."
Wyard adds that many of the vitamins, once isolated and purified, no longer contain any genetically modified DNA. Even so, organic products cannot use GMO-derived nutrients.