It’s estimated that approximately 2 billion people around the world suffer from zinc deficiency, especially in developing country and amongst the elderly in developed countries.1 Vegetarians and vegans are also at increased risk of deficiency as well as those with kidney disorders and excessive diarrhea.1
Symptoms of deficiency include slow growth, immune deficiency, loss of hair, testicular atrophy, and skin disorders. Zinc plays an important role in reducing oxidative stress and inflammation.1 It’s thought that zinc deficiency may also contribute to conditions like rheumatoid arthritis, diabetes, macular degeneration, atherosclerosis, and cognitive disorders.1
Zinc is found primarily in foods with significant protein content such as red meat, oysters, seafood, poultry, eggs, beans/peas, nuts, seeds, and soy.
Like most minerals and vitamins, zinc does not function alone and getting too much of it without enough of the other necessary nutrients can cause imbalances and health problems. In the case of zinc, one of the minerals you need to pay special attention to is copper. Excessive intake of zinc can reduce your body’s absorption of copper, potentially leading to a copper deficiency.1–3
We don’t recommend taking high doses of any single mineral without relevant blood tests and supervision by a medical professional. Both zinc and copper can be toxic in excess, especially when taking as individual ingredients. We instead recommend approaches that use a balance of nutrients with required cofactors, the way those nutrients are found in a healthy and balanced diet.
Zinc supplements and lozenges are frequently marketed for boosting immune health, especially when you start to feel the symptoms of cold or flu setting in. While some studies have shown improvements in cold and flu symptoms and decreased duration of illness, there are just as many studies showing no difference.3,4
The evidence when taken as a whole shows no definite benefit to taking a zinc supplement to prevent or get over an illness. Be aware that some zinc-containing nasal gels and sprays have been associated with the loss of the sense of smell while offering no benefits with regards to reducing the severity or duration of cold and flu symptoms.3 However, it is clear that zinc is required for proper immune function, and zinc deficiency is clearly associated with decreased immune function.
Your immune system requires other nutrients besides zinc to operate at full capacity, so instead of taking a supplement containing only zinc, you are better off finding a well-balanced multivitamin that contains zinc along with other essential vitamins, antioxidants, amino acids, and minerals – including copper. On top of that, you can also incorporate immune boosting antioxidants, Vitamin D3, essential omega-3 oils, and even prebiotic fiber that supports a healthy intestinal microbiome.
Kyle Hilsabeck, PharmD., is the Vice President of Pharmaceutical Affairs at McCord Holdings and licensed by the Iowa Board of Pharmacy. He completed bachelors degrees in biology and biochemistry at Wartburg College before earning his Doctorate of Pharmacy from the University of Iowa College of Pharmacy. Upon graduation, he completed a community pharmacy practice residency through the University of Iowa where he focused primarily on nutritional aspects of care including the use of vitamin, mineral, and herbal supplements. He has taught courses for the University of Iowa College of Pharmacy on vitamins, minerals, herbs, and nutritional supplements and given many presentations on the subject as well. He has a passion for improving patient care specifically with regards to the safety and quality of the nutritional supplements and health information people use.
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