01/22/2003

Zinc Deficiency Distinct Possibility in 25 Percent of Canadians
New analysis of the Food Habits of Canadians Study, by McGill University researchers, indicates that close to one out of four Canadian adults have diets that are low in zinc. According to a nutrition scientist, whose research specialty is zinc, these new figures suggest that many Canadians are likely at risk for zinc deficiency.

Zinc plays a key role in immune function where it is needed in order for the body to develop its own natural “killer” cells to fight infection. It also has many other functions, including a central role in growth and reproduction.

“Until now, moderate zinc deficiency has been generally ignored in Canada because we don’t have reliable laboratory methods to test for zinc deficiency,” says Dr. Fiona Yeudall, a registered professional dietitian and assistant professor in the School of Nutrition at Ryerson University in Toronto. “To date, the only measure of zinc deficiency has been the growth response in children after being given a zinc supplement. But that doesn’t mean that the consequences in adults aren’t just as serious.”

Yeudall is particularly concerned about the impact on babies born to mothers whose intake of zinc is low. During pregnancy, zinc needs increase by about one-third. Yet the new dietary data suggests that 26 percent of teenage girls and 22 percent of adult women are entering pregnancy at risk for zinc deficiency.

“Zinc deficiency during pregnancy could impair the development of the fetus’ immune system, leaving the infant more susceptible to infections,” explains Yeudall.

While prenatal vitamin supplements usually contain zinc, Yeudall doesn’t see pills as the total answer. “For all people, I recommend foods as the best source of zinc. After all, to efficiently absorb the zinc from supplements, you need protein from animal sources – such as meat, poultry and fish.”

Beef is the richest, commonly-eaten food source for zinc. In fact, one serving of beef provides about half the Recommended Dietary Allowance for zinc for teens and adults of both sexes. Other food sources include pork, poultry and seafood.

Legumes and whole grains also contain zinc, but Yeudall points out that phytates in legumes and soy interfere with zinc absorption. “People who don’t include meat, fish and poultry in their diet to help with zinc absorption actually need up to 50 percent more zinc in their diet.”

“Improving the diet can set good habits for life. And with foods, there is no risk of toxicity,” concludes Yeudall.

For more information, visit the zinc section on our website.
Download Zinc and Your Health - a factsheet with with action tips to maximize your zinc intake.
Curried Beef and Lentils, a zinc-rich dish, provides almost half the Daily Recommended Intake for zinc.