The facts about Zinc and the Immune System

Thursday April 16, 2020

Many people have inquired if they should start taking zinc supplements to “boost” their immune system and help protect themselves from Covid 19.  No supplement will ever increase immune system function however nutritional deficiencies of all kinds can contribute to a weakened immune system. Here are some great facts about zinc taken from the National Institutes of Health.

What is Zinc?

Zinc is an essential mineral which means that Zinc cannot be made by the body but must be consumed in some way.  It is essential for protein synthesis (wound healing), growth, pregnancy, cell division and most notably it plays a role in the immune system.

Why is zinc important to the immune system?

Even mild or moderate zinc deficiency significantly impacts immune function impairing macrophage and t cell activity. Low zinc status has been associated with increased susceptibility to pneumonia and other infections.

How much do I need?

The DRI for men and women is 11 mg and 8 mg respectively.

Where do I find zinc?

While the greatest source of zinc is oysters with a whopping 74 mg per 3 ounce serving, there are other foods such as beef, shellfish, beans yogurt, and cheese are also great sources.

Other sources of zin can be found in over the counter (OTC) treatments for colds and is present in some denture adhesive creams.  Note: heavy use of nasal sprays with zinc can cause anosmia (loss of sense of smell) and can be permanent.  This is not found with the lozenges.

Am I at risk for low Zinc levels?

While the United States considers most children and adults likely get adequate amounts of zinc in their diet, older adults’ intake of zinc could be marginal even with supplements.  There is not an adequate test to determine adequate levels of zinc.   Additionally, there are medications that are often prescribed for older adults such as hydrochlorothiazide (Esidreiz and HydroDIURIL) that increase zinc losses.

Other populations that are at high risk for zinc deficiency are older infants above age 7 months that are exclusively breast fed, pregnant and lactating women, alcoholics, vegetarians (plant sources of zinc are not as readily absorbed as animal sources).  People that have gastrointestinal diseases such as Crohn’s disease, and ulcerative colitis are at high risk due to malabsorption issues.

You can over do the zinc with significant detrimental health effects. Zinc toxicity causes a multitude of symptoms such as nausea and vomiting and can in the long term deplete copper levels, alter iron function and reduce immune system (seriously-again) There are upper tolerable limits that should be avoided be avoided of 40 mg for adults.  Can I get too much zinc?

Overall, try to eat a variety of foods.  If you are having difficulty determining if you need extra zinc, contact your healthcare provider or registered dietitian.

National Institutes of Health Zinc Supplements https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/  accessed 3/2020