Zinc: Benefits, Immune Support and How Much You Need

Zinc is a mineral that's found in cells throughout your body, and it's one of the most important nutrients for your immune system [1]. It also helps wounds heal, supports your sense of taste and smell, and helps your body grow and make new cells [1].

What is zinc?

Zinc is a mineral your body needs to stay healthy, and it's found in cells all throughout your body [1]. You get it from the foods we eat, especially oysters, meat, poultry and seafood, and yes, from supplements. Almost every multivitamin contains some zinc [1].

Here's something important about zinc: your body has no special way to store it. That means you need a steady supply from your diet every day to keep your levels where they should be [1].

Supplements use several forms of zinc, such as zinc sulfate, zinc acetate and zinc gluconate. So far, research hasn't shown that one form is clearly better than the others [1].

What does zinc do for the body?

Zinc's best-known job is helping your immune system fight off invading bacteria and viruses [1].

Zinc is important to four things inside the human body: growth and new cells, healing, taste and smell, and the immune system. Let's take each one individually.

• Growth and new cells: Your body uses zinc to make DNA and proteins. During pregnancy, infancy, childhood and the teen years, zinc is needed to grow and develop properly [1].
• Healing: Zinc helps wounds heal [1].
• Taste and smell: Zinc is important for your sense of taste, and low zinc at any age can dull both taste and smell [1].
• The immune system: And the last one. Zinc is essential for the normal development and work of many immune cells, from the first responders to the T cells that target specific germs [2].

Why is zinc important for the human body?

Without enough zinc, children can have slow growth, diarrhea, loss of appetite and frequent infections. At any age, low zinc can cause a loss of taste and smell, and in older adults it can slow wound healing and affect thinking and memory [1]. In fact, zinc wasn't recognized as essential for human health until 1963, when a researcher linked it to growth problems in young men in Iran [4].

Most people in the United States get enough zinc from food [1]. But because your body doesn't store it, certain groups can fall short more easily, including vegetarians and vegans, pregnant and breastfeeding women, and people with digestive conditions or alcohol use disorder [1].

Zinc also ties directly into the two processes research links to declining health with age: increased oxidative stress, which is damage from excess free radicals, and chronic inflammation [3]. Zinc acts as an antioxidant and helps calm the body's inflammatory signals [4]. That's why comprehensive micronutrient formulations include zinc alongside antioxidants, B vitamins and other minerals [5] [6]. Zinc does its best work as part of the team, not by itself.

How does zinc support immune function?

Zinc supports immune function by helping your immune cells develop and work normally, and by acting as a signal inside those cells that helps direct their response [2] [4]. Even a moderate shortfall can weaken your immune defenses [2].

Think of your immune system as having two jobs: responding strongly when a threat shows up, and calming back down once the job is done. Zinc helps with both. Let's look at how.

• First-line (innate) defense: This is your body's rapid-response team. Zinc is crucial for neutrophils and natural killer cells to develop and work properly. Without enough zinc, macrophages are less able to engulf and destroy germs [2].
• Targeted (adaptive) defense: This is the part of your immune system that learns and remembers specific threats. Zinc supports the growth and work of T cells and B cells. It's also needed to activate thymulin, a hormone made by the thymus gland, where T cells mature [2].
• Balanced inflammation: Zinc is an antioxidant and an anti-inflammatory. It helps switch off the signals that drive excess inflammation, so the immune response stays in proportion [4].

What about zinc and colds? Some studies suggest zinc lozenges or syrup can help you recover faster if you start taking them right when a cold begins, but they don't seem to make symptoms less severe [1]. Researchers are still working out the best dose and form.

Getting the most from zinc

If you want to get the most out of zinc, here are five things the research points to.

• Get some every day: Because your body doesn't store zinc, a steady daily supply matters more than an occasional big dose [1].
• Keep the amount sensible: The Micro Daily EMF formula provides 15 mg of zinc (as zinc bisglycinate) a day, 136% of the Daily Value [7]. That's comfortably below the 40 mg daily upper limit for adults [1]. Research-based formulations have long used a glycine-bound form of zinc [6].
• Don't take it alone: Zinc works as a team with antioxidants, B vitamins and other minerals, which is how research-based formulations combine it [3] [6].
• Take your formula twice a day: Comprehensive formulas are designed to be split into a morning dose and an evening dose. Since your body doesn't store zinc, steadier daily intake is a good fit [8] [9].
• Help your body absorb it: Zinc from meat and seafood is absorbed better than zinc from beans and grains, which contain phytates that hold on to zinc. Taking 25 mg or more of supplemental iron at the same time can also lower how much zinc you absorb [1].

One last thing to keep in mind: with zinc, more isn't better. Taking too much for a long time can actually lower your immunity, reduce your HDL ("good") cholesterol and cause low copper levels. Very high doses can also interfere with how you absorb magnesium [1].

Frequently asked questions about zinc

How much zinc do I need each day?

Adult men need 11 mg a day and adult women need 8 mg. During pregnancy that rises to 11 mg, and while breastfeeding to 12 mg. Children need 3 to 8 mg, depending on age [1]. The upper limit from all sources is 40 mg a day for adults [1].

What foods are high in zinc?

Oysters are in a league of their own, with about 28 to 32 mg in 3 ounces. Three ounces of roasted beef sirloin has about 3.8 mg and blue crab about 3.2 mg. A serving of fortified breakfast cereal can provide about 2.8 mg, and an ounce of roasted pumpkin seeds about 2.2 mg [1].

Does zinc help with colds?

It might help a little. Some studies suggest that zinc lozenges or syrup, started right when a cold begins, can help you recover faster, but they don't seem to make symptoms milder [1]. The best dose and form are still being studied.

Who is most likely to be low in zinc?

The groups most at risk are vegetarians and vegans, pregnant and breastfeeding women, and breastfed babies over 6 months old. People who've had digestive surgery or have conditions such as Crohn's disease or ulcerative colitis, children with sickle cell disease and people with alcohol use disorder are also at higher risk [1].

What are the signs of low zinc?

In children, low zinc can cause slow growth, diarrhea, loss of appetite, hair loss and frequent infections. At any age, it can cause a loss of taste and smell. In older adults, it can slow wound healing and affect memory and thinking [1]. Many of these signs have other causes too, so it's worth checking with your healthcare provider [1].

Can you take too much zinc?

Yes. Too much zinc can cause nausea, dizziness, headaches, an upset stomach, vomiting and loss of appetite. Taking too much for a long time can lower your immunity and your copper levels [1]. Zinc can also interact with some antibiotics, so it's best to take them a few hours apart [1].

Explore more micronutrients

Zinc works alongside other nutrients. Learn more about vitamin D, magnesium, iron, vitamin B12, calcium, potassium and folate.

Key sources: NIH Office of Dietary Supplements, Zinc Fact Sheets for Health Professionals and Consumers [1]; Prasad AS, "Zinc in Human Health: Effect of Zinc on Immune Cells," Molecular Medicine, 2008 [2]; Prasad KN, Micronutrients in Health and Disease, CRC Press, 2019 [3]. Every numbered citation links to its full entry on our References page.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Talk with your healthcare provider before starting any supplement, especially if you are pregnant, nursing, taking medication or have a medical condition.