You've probably seen the headlines touting soy as the newly discovered miracle food. In 1998, the Federal Drug Administration released a statement that said, "25 grams of soy protein a day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease." The claims didn't stop there. Further studies showed that soy consumption resulted in lower risk of certain kinds of cancers. As the list of health benefits attributed to soy became longer, soy started showing up everywhere __ in shakes, burgers, cereals, even in concentrated pill form.
For busy vegetarian parents, this boom in soy convenience foods makes feeding finicky children much easier. Most toddlers love tofu pups and soy burgers make neighborhood barbecues much more palatable. But how much soy is too much? Can the powerful phytoestrogens that make soy such a healthful choice ever be harmful?
Mark Messina, PhD, MS is co-founder and editor of the peer-reviewed journal Vegetarian Nutrition: An International Journal and the co-author of The Simple Soybean and Your Health (Avery Publishers, 1994). He says that soy foods can be a boon to children's diets.
Little research has been done.
"The effects of soy in children has not been studied extensively," he says. "Although soy protein has been shown to lower cholesterol and to promote growth in this population. There is also much interest in the possibility that [childhood] exposure to soy may reduce later risk of developing breast cancer although this hypothesis is still quite speculative."
Diet diversity is the way to go Reed Mangels PhD, RD of the Vegetarian Resource Group says soy, "is nutritious, adds dietary variety, and is convenient" but worries that their convenience can make parents "over reliant" on them.
"For my own children," she says. "I try to keep them to a couple of glasses of soymilk (8-10 ounces total for the day) and a serving of soy foods on average although I don't go crazy about this." Mangels recommends that parents remember that there are other convenient forms of protein like canned beans and seitan.
Messina says this advice is right on the money. "I think two servings of soy per day is a reasonable amount [for a young child] to consume when one considers both Asian soy consumption and the importance of eating a variety of foods, but this is not to suggest in anyway that three servings per day is unadvisable."
Natural soy for natural kids.
Heavily processed soy foods-like the burgers, cheeses, and "recipe crumbles"-are fine but should be used in moderation. Processing strips soybeans of some of their nutritional value. Healthier choices include tempeh, tofu, miso, soy milk, and of course, edamame.
Sweet protein shakes using soy powder and protein bars that taste like candy may seem like a harmless treat for children but kids don't need soy supplements. Soy powders used in these concoctions may contain much higher concentrations of isoflavones than are found naturally occurring in soy foods. Genistein and diadzein are the names of two isoflavones that crop up on ingredient lists most often so read your labels. Better yet, keep meal replacement bars and protein shakes out of little hands.
Soybean oil is cheap and popular and it gets used a lot in commercial foods. Be sure to read labels but remember that many processed foods use hydrogenated vegetable oil __ very often that's soy oil. If your family is eating a lot of processed food, then it can be difficult to monitor your soy intake.
And as always, use organic whenever possible. In North America, any soy labeled "organic" is guaranteed free of genetically-modified soybeans.
What about soy formula?
Mark Messina says that it "appears soy formula is an appropriate alternative to dairy milk-based formulas." Noting that "the complete lack of published reports suggesting any unwanted effects in infants that can in anyway be attributed to soy formula is certainly impressive considering the millions of infants fed soy formula the past 30 years."
Reed Mangels agrees, stating that while she is a "real advocate of breastfeeding [I] recognize that there are situations where this is not possible." She cites the American Academy of Pediatrics when she says that "growth of infants on soy formulas is comparable of that to infants fed breast milk or cow's milk formulas."
