Zinc is an essential mineral that is found in almost every cell. It stimulates the activity of approximately 100 enzymes, which are substances that promote biochemical reactions in your body. Zinc supports a healthy immune system, is needed for wound healing, helps maintain your sense of taste and smell, and is needed for DNA synthesis.

Zinc and Your Vision

Zinc also affects your vision. It has been known for some time your vision will not remain sharp without it. However, too much can be damaging. At moderate levels, zinc protects retinal cells from antioxidant damage, which might prevent age-related macular degeneration, a leading cause of blindness. At too-high levels, zinc destroys healthy retinal cells. The safe, recommended supplemental dose is 25mg of an easily absorbed chelated type of zinc such as Zn L-monomethionine.

Your body needs zinc to use nutrients for immunity, for wound healing and for maintaining your senses of taste and smell. It is very difficult to get too much zinc in your diet; however, supplements may cause harmful side effects if you do not need them. Side effects could include: Lowering of HDL (good) cholesterol levels, weakening of immune response and impairing of copper absorption. Zinc is found in many different foods from both animal and plant sources so you can usually get all you need from a variety of foods.

Where you get Zinc: Beef, poultry, liver, oysters, eggs and dairy products.

Spices and herbs that contain zinc are black pepper, cayenne, chili, cinnamon, ginger, turmeric, sage, thyme, cumin, coriander, dill, allspice, fennel, fenugreek, marjoram, rosemary, curry, garlic, paprika, salt, nutmeg, anise, caraway seed, savory, parsley and chervil.

Foods of animal origin are the best sources: Lean meat, poultry, and some seafood, liver and, in small amounts, milk and eggs. In fact, the body absorbs zinc better from a diet rich in animal protein than from one high in plant protein. You also get zinc from whole-grain foods, nuts, potatoes, spinach, pumpkin or sunflower seeds, plain yogurt, cheese, fortified breakfast cereals and some legumes, but phytates in those foods can decrease its rate of absorption.

Zinc and Inflammation

In a study in which participants took 45 milligrams of zinc daily for six months, tests showed significantly lower levels of markers that signal dangerous inflammation. Zinc may control inflammmation by decreasing compounds called cytokines.

Low zinc status has been observed in 30 to 50 percent of alcoholics. Alcohol decreases the absorption of zinc and increases loss of zinc in urine. In addition, many alcoholics do not eat an acceptable variety or amount of food, so their dietary intake of zinc may be inadequate.

Zinc and Diarrhea

Diarrhea results in a loss of zinc. Individuals who have had gastrointestinal surgery or who have digestive disorders that result in malabsorption, including sprue, Crohn’s disease and short bowel syndrome, are at greater risk of a zinc deficiency. Individuals who experience chronic diarrhea should make sure they include sources of zinc in their daily diet and may benefit from zinc supplementation. A medical doctor can evaluate the need for a zinc supplement if diet alone fails to maintain normal zinc levels in these circumstances.

Zinc and the Common Cold

The effect of zinc treatments on the severity or duration of cold symptoms is controversial. Additional research is needed to determine whether zinc compounds have any effect on the common cold. If you do get sick, one or two zinc lozenges at the first sign could shorten the length of your suffering.

Zinc safety tip: If you are getting 100-percent of the Daily Value of zinc (15mg) in your multivitamin, try not to take more than 25mg of extra zinc so you do not go above the safe upper limit of 40mg. Also note: Overzealous dosing can cause permanent loss of smell in some people.

Zinc Deficiency

If you are deficient in zinc, symptoms include reduced immunity, appetite loss, skin changes and impaired growth – and, during pregnancy, birth defects. The causes are poor intake, poor absorption, zinc loss or increased need. Vegetarians may need more since zinc from plant sources is not absorbed as well as zinc from other sources. Fortified cereal may be the best source. An American study showed that over 50 percent of children in the US aged 2 to 10 had a zinc intake below the recommended daily values.

There are some health-conditions linked to poor zinc status: Digestive diseases, alcoholism, inadequate calorie intake and poor infant and childhood growth. The USDA found that high fat, low-carbohydrate diets do not provide an adequate supply of zinc. If you suspect a deficiency, talk to your doctor about your symptoms before trying a supplement.

Zinc and Better Sex

Most of us have heard that oysters are a sexy super food – but the reason for this is due to the zinc content in oysters. Zinc helps the body produce testosterone, a hormone critical in regulating both women and men’s libido and sexual function. Research suggests that zinc can improve sperm count and swimming ability, and increase sexual potency in men. For women, zinc may help ovaries – the source of estrogen and progesterone and some testosterone – stay healthy, keeping a woman primed for bedroom action.

Are There Any Potential Drug Interactions?
Zinc may be contra-indicated with certain antibiotics. Consult your physician for more information.

References: The Complete Book of Vitamins and Minerals. Pennsylvania, Rodale Press. The Essential Guide to Vitamins and Minerals. New York, HarperPerennial.

Read More: Essential Nutrients