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Boost Your Intake of Key Trace Minerals

Trace minerals such as zinc and iron are absolutely vital for your immune function, among other things. Here’s our guide to the most important ones and how to make sure you’re getting enough of them.

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In middle age, Jane was experiencing multiple health problems. She was being treated by a nutritionally oriented physician for several health issues — all of which were helped by trace minerals. For Jane’s hypothyroidism, the doctor prescribed natural thyroid hormones and also recommended that Jane begin taking iodine and selenium supplements. For her blood sugar problems, he asked her to adopt a high-protein, low-carb diet and to take extra chromium. Because Jane was also iron deficient and chronically fatigued, he recommended that she take iron supplements as well. Within several weeks of beginning this regimen, Jane said she felt better than she had in years.

DID YOU KNOW? Using a cast-iron skillet for cooking is a good way to obtain dietary iron.

The Basics

Calcium, magnesium, and sodium get the most attention as minerals — after all, they are the heavyweights among essential dietary minerals. Trace minerals, however, are no less essential for health. They are necessary, just in smaller amounts. Trace minerals include zinc, copper, iron, chromium, selenium, iodine, manganese, and molybdenum.

How They Work: Trace minerals serve myriad biochemical functions. In these different roles, they act as constituents of hormones, cofactors needed for energy production, coenzymes to initiate chemical reactions, and many other biological processes.

Health Benefits: Trace minerals typically multitask-that is, they have diverse roles in our health.


Zinc plays a fundamental role in the activity of genes, forming what geneticists call zinc fingers because of their shape. For example, zinc fingers are involved in activating genes and linking DNA to RNA. Zinc deficiencies interfere with the activity of these genes. Zinc is also needed to make copper-zinc superoxide dismutase, one of the most potent antioxidants in the body. The mineral is required in the manufacture of metallothionein, a small family of enzymes that protect us from lead and cadmium. Zinc is also needed for normal taste sensation. White spots on fingernails are a sign of zinc deficiency.


Copper is used in a key enzyme that breaks down food molecules for energy. Copper also is needed for normal immunity. In general, your supplements should contain a ratio of between 1:15 and 1:30 copper to zinc (i.e., 1 milligram of copper to between 15 and 30 milligrams of zinc). Too much copper can suppress zinc levels, and vice versa.


Iron is also needed for enzymes involved in energy production, which is why iron deficiency is often characterized by fatigue. Your body also uses iron to make hemoglobin, the part of red blood cells that carries oxygen to tissues. Check with your doctor before taking high-dose iron supplements, because too much can cause health problems.


Chromium helps insulin transport glucose from the blood into cells, and supplements can greatly improve blood sugar levels. In a study of 180 people with type 2 diabetes, taking 500 micrograms of chromium picolinate twice daily resulted in significant improvements in blood sugar and insulin levels after just four months. Niacin-bound chromium has similar benefits. Chromium supplements can also reduce depression in people with a history of overeating.


Selenium is needed to make glutathione peroxidase, a potent antioxidant. It enhances immunity and aids the body’s ability to fight a wide range of infections. Its antiviral activity was shown in a study of 174 HIV-positive men and women who took selenium supplements for nine months. Subjects taking selenium had increases in immune cells and decreases in viral load, while those who took placebos had substantial increases in viral concentrations. Selenium supplements may be especially beneficial for women who inherit mutations in the BRCA cancer gene. In a study of women with this gene mutation, selenium supplements significantly decreased the rate of gene damage.


Iodine is an essential constituent of thyroid hormones, which regulate our metabolism. The principal thyroid hormones are T4 (which contains four iodine atoms) and the active T3 form (which contains three thyroid atoms). Selenium is needed to convert T4 to T3. Both minerals should be included in any treatment for low thyroid activity. 


Manganese works with chromium and zinc in maintaining our ability to properly use carbohydrates. And like zinc and copper, it is also needed to make the antioxidant superoxide dismutase. Some studies have linked manganese deficiencies to seizure disorders, and the mineral also plays important roles in the formation of cartilage.
Molybdenum is needed to form aldehyde oxidase, sulfite oxidase, and xanthine oxidase. These enzymes help the body break down sulfites and aldehydes, the latter being a toxic by-product produced by yeast infections.

Background Check 

There are still other important trace minerals: cobalt is part of the vitamin B12 molecule; boron helps strengthen bones; and vanadium can improve carbohydrate tolerance.

What You Should Take 

All of these minerals should be found in multimineral supplements. Under some circumstances, you may need extra amounts of zinc, copper, iron, chromium, selenium, and iodine.