Z is the last letter in the alphabet, which means it often receives little or no attention. Yet Z is the first letter in the word “zinc.” How much thought have you ever given to zinc? Maybe some, if you take zinc supplements for a cold, for example. But new research indicates that zinc is something else that people with diabetes should think about. Why? Read on.
In case you’re wondering what the heck zinc does, it’s helpful to know that it’s an essential mineral that plays very important roles in the body. The body can’t make zinc, so we must take it in from food sources. Zinc is stored in the muscles, blood cells, retina of the eye, skin, bone, kidney, liver, pancreas, and in men, prostate.
What does zinc do for us? Primarily, zinc helps the immune system function properly. It’s also needed for cell growth and division, wound healing, and the breakdown of carbohydrate for energy. We need zinc to maintain our sense of taste and smell, too. Finally, zinc is an antioxidant, protecting our cells from free radicals, or molecules that can wreak havoc and possibly lead to heart disease and cancer.
Zinc is found in many foods. The main sources of zinc in the American diet are red meat, poultry, and seafood, but it’s also found in legumes, whole grains, nuts, and dairy foods. Zinc is better absorbed from animal foods than from plant foods, since compounds called phytates that are found in plants can hinder its absorption. Daily zinc requirements are 11 milligrams for adult men and 8 milligrams for adult women. Symptoms of zinc deficiency include stunted growth (in children), hair loss, diarrhea, decreased appetite, eye and skin lesions, delayed wound healing, and weight loss. People with chronic gastrointestinal disorders, such as Crohn disease, are at risk for zinc deficiency.
How does zinc relate to diabetes? Interestingly, zinc has long been an ingredient used in “older” insulins, such as Regular, NPH, and Lente. Zinc is also necessary for the formation of insulin in the pancreas’s beta cells. For these reasons, researchers have looked at the role of zinc supplementation in the prevention and treatment of Type 2 diabetes—unfortunately, without success.
However, new light has been shed on the role of zinc in diabetes. In this month’s issue of Diabetes Care, Finnish researchers followed 1,050 adults with Type 2 diabetes for seven years. During that time, 156 participants died from heart disease and 254 had fatal or nonfatal heart attacks. Blood zinc levels were lower in people who died from heart disease compared to those who survived; also, zinc levels were lower in those who had heart attacks. The authors of this study speculate that, possibly because zinc has antioxidant properties, supplementation may be useful in warding off heart disease in people with Type 2 diabetes.
Don’t start popping zinc pills just yet (unless it’s under the supervision of your health-care team); we still need to learn more. Too much zinc can upset the balance of copper and iron in the body, can weaken the immune system, can lower levels of HDL (”good”) cholesterol, and can cause nausea and vomiting. Zinc supplements can interfere with the absorption and function of many medicines, including ACE inhibitors, some antibiotics, hormone replacement therapy, and corticosteroids. To be on the safe side, aim to get your zinc from food sources, as mentioned above. You’ll also get zinc if you take a multivitamin/multimineral supplement.