Zinc Benefits: What Zinc Does for the Body and What Studies Measured

Zinc is an essential mineral that hundreds of enzymes need to work, and its main benefits are supporting normal immune function, protein and DNA building, wound repair, cell growth and the senses of taste and smell. Your body cannot make zinc, so it has to come from food or supplements every day: 11 mg for men and 8 mg for women. In a trial of older adults who started with low zinc, 30 mg a day for 3 months raised blood zinc and the number of T cells, a key type of immune cell.

Key Takeaways

• Zinc is required for the activity of hundreds of enzymes and plays a role in immune function, protein and DNA synthesis, wound repair, and cell signaling and division (NIH ODS: Zinc).
• Adults need 11 mg a day (men) or 8 mg (women), and the upper limit is 40 mg a day from food and supplements combined.
• About 15 percent of US adults take in less than the average requirement, and older adults and people who eat mostly plants are more likely to fall short.
• In 31 nursing home residents aged 65 and older with low blood zinc, 30 mg a day for 3 months raised blood zinc and T cell numbers (Barnett et al., 2016).
• More is not better: 50 mg or more a day for weeks can interfere with copper absorption.

What Is Zinc?

Zinc is an essential trace mineral, which means your body needs it in small amounts and cannot make it. It is found naturally in foods such as shellfish, meat, seeds and whole grains, it is added to some fortified foods, and it is in many multivitamin and mineral products (NIH ODS: Zinc). An adult body holds only about 1.5 g of zinc in women and 2.5 g in men, mostly in skeletal muscle and bone, which is why a steady daily intake matters.

What Does Zinc Do for the Body?

Zinc works behind the scenes in almost every cell. These are the jobs the NIH Office of Dietary Supplements lists (NIH ODS: Zinc):

Role	What it means for you
Enzyme activity	Hundreds of enzymes need zinc to do their work
Immune function	Supports the normal work of immune cells
Protein and DNA synthesis	Helps build new proteins and copy genetic material
Wound repair	Needed for normal skin repair; low zinc in older adults can slow it
Cell signaling and division	Supports cell growth and renewal
Taste and smell	Involved in taste; low zinc can dull taste and smell
Growth	Supports healthy growth and development, including during pregnancy

Because zinc touches so many systems, the benefits of getting enough are broad rather than dramatic: it keeps everyday processes running as they should. Our immune system guide covers zinc alongside the other nutrients that support normal immune function.

Zinc Benefits: What Studies Measured

Immune support in older adults

Older adults are one of the groups most likely to have marginal zinc intakes. In a randomized, double-blind trial, 31 nursing home residents aged 65 and older who started with low blood zinc took 30 mg of zinc or a placebo every day for 3 months. Zinc raised blood zinc by 16 percent more than placebo and increased the number of T cells, a key type of immune cell (Barnett et al., 2016). Not everyone reached a normal level in 3 months, which points to steady, longer use for people who start low.

Mood in young women

In a 10-week pilot study, 30 young women took a multivitamin either with or without 7 mg of zinc. The zinc group had higher blood zinc and better scores on a standard mood questionnaire, while the multivitamin-only group showed no such change (Sawada and Yokoi, 2010). It was a small, early study, using a modest dose close to the daily target.

How well supplements are absorbed

Absorption is about 61 percent for zinc citrate and gluconate in young adults and 50 percent for zinc oxide (NIH ODS: Zinc). In a crossover study of 12 healthy women given a single 15 mg dose, zinc bisglycinate raised blood zinc 43.4 percent more than zinc gluconate (Gandia et al., 2007). Our guide to zinc picolinate vs bisglycinate vs gluconate covers the forms in depth, and our zinc bisglycinate ingredient page explains the form we use.

A note on zinc lozenges

Zinc lozenges are studied for a different purpose than daily zinc and at different amounts. Our guide to how much zinc per day covers what that research measured.

Benefits of Zinc for Men and Women

Zinc does the same jobs in everyone, but needs and intakes differ (NIH ODS: Zinc):

	Men	Women
RDA, 19 and older	11 mg a day	8 mg a day (11 mg pregnant, 12 mg breastfeeding)
Average from food	13 mg a day	9.2 mg a day
Average with supplements	16.4 mg a day	12.6 mg a day
Zinc in the body	About 2.5 g	About 1.5 g
Upper limit	40 mg a day	40 mg a day

For men: the higher target reflects a larger body store, most of it in muscle and bone. Men average 13 mg a day from food, above the target, while men who eat mostly plants may fall short. For women: the target is lower, but women average only about 1.2 mg above it from food, and needs rise in pregnancy and while breastfeeding. Iron supplements of 25 mg or more can lower zinc absorption when taken at the same time, so space them apart.

Who Is Most Likely to Fall Short

About 15 percent of US adults take in less zinc than the Estimated Average Requirement. The groups most likely to have low zinc status include (NIH ODS: Zinc):

• People who eat mostly plants: phytates in legumes and whole grains bind zinc and lower absorption, and vegetarians usually have lower zinc intakes and blood levels.
• Older adults: intakes can be marginal, and low zinc can slow wound repair.
• Pregnant and breastfeeding women: needs rise by 3 to 4 mg a day, and 11 percent of pregnant women fall below the average requirement.
• People with digestive conditions or weight loss surgery that reduce how much zinc they absorb.

Low zinc can show up as a poor appetite, a dulled sense of taste or smell and slow wound repair. If you think you run low, talk with your clinician.

Getting Zinc From Food and Supplements

Oysters are the richest source by far, at 32 mg in 3 ounces, followed by beef (3.8 mg in 3 ounces of roasted bottom sirloin), blue crab (3.2 mg), cooked oats (2.3 mg a cup) and roasted pumpkin seeds (2.2 mg an ounce). Food absorption ranges from 5 percent to more than 50 percent depending on how many phytates come with it (NIH ODS: Zinc). Our guide to foods high in zinc has the full list.

For supplements, three practical points:

• Count elemental zinc: the Supplement Facts panel declares the zinc itself, not the weight of the whole compound.
• Magnesium is a fine partner: zinc interferes with magnesium only at very high amounts, 142 mg a day. See magnesium and zinc together.
• Zinc and vitamin D: zinc is one of the minerals often grouped as vitamin D cofactors, with magnesium and boron. See vitamin D cofactors and boron benefits.

Is Zinc Safe?

Most people tolerate zinc well at everyday amounts, and food alone rarely supplies too much. Taking far more than you need can cause nausea, dizziness, headaches, stomach upset, vomiting and loss of appetite, and 50 mg or more a day for weeks can interfere with copper absorption and reduce immune function (NIH ODS: Zinc). The 40 mg upper limit covers food and supplements together and was set to protect copper status, so add up every label you take. If zinc upsets your stomach, take it with a meal. If you are pregnant, breastfeeding or take prescription medicine, check with your clinician first.

Where Our Vitamin D Cofactor Capsules Fit

Our Vitamin D Cofactor Capsules are coming soon. Each 2-capsule serving gives 10 mg of zinc and 100 mg of magnesium as bisglycinate, plus 3 mg of boron as glycinate, made with third-party tested ingredients. That is close to the daily zinc target for both men and women, and well under the 40 mg limit when added to an average diet. The capsules are designed to pair with our Vitamin D3 + K2 Drops, one drop a day with a meal that has some fat. You can join the waitlist on the product page.

Benefits build with consistent daily use: months 1 to 2 can bring early changes, and 3 months and beyond is where the full benefit builds.

Frequently Asked Questions

What does zinc do for the body?

Zinc helps hundreds of enzymes work and supports immune function, protein and DNA building, wound repair, cell growth and the senses of taste and smell.

What is zinc good for?

Zinc is mainly used to support normal immune function and to keep everyday processes such as protein building and skin repair running well, especially for people whose diet runs low.

What are the benefits of zinc supplements?

A supplement helps close the gap when food falls short. In older adults who started low, 30 mg a day for 3 months raised blood zinc and T cell numbers.

What are the benefits of zinc for men?

Men need more zinc than women, 11 mg a day, and hold about 2.5 g in the body, mostly in muscle and bone. Zinc supports their immune function and protein building like everyone else's.

What are the benefits of zinc for women?

Women need 8 mg a day, more in pregnancy and while breastfeeding. A small pilot in young women linked 7 mg of added zinc with better scores on a mood questionnaire.

Is it OK to take zinc every day?

Yes. Zinc is needed daily. Keep your total from food and supplements under 40 mg a day.

How long does zinc take to work?

The trial in older adults measured changes over 3 months, and not everyone reached a normal level in that time, so think in months of steady use.

Can I take zinc and magnesium together?

Yes. Zinc interferes with magnesium only at very high amounts, 142 mg a day, far above the 40 mg upper limit.

Sources

• National Institutes of Health, Office of Dietary Supplements. Zinc: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
• Barnett JB, et al. Effect of zinc supplementation on serum zinc concentration and T cell proliferation in nursing home elderly: a randomized, double-blind, placebo-controlled trial. American Journal of Clinical Nutrition, 2016. https://pubmed.ncbi.nlm.nih.gov/26817502/
• Sawada T, Yokoi K. Effect of zinc supplementation on mood states in young women: a pilot study. European Journal of Clinical Nutrition, 2010. https://pubmed.ncbi.nlm.nih.gov/20087376/
• Gandia P, et al. A bioavailability study comparing two oral formulations containing zinc (Zn bis-glycinate vs. Zn gluconate) after a single administration to twelve healthy female volunteers. International Journal for Vitamin and Nutrition Research, 2007. https://pubmed.ncbi.nlm.nih.gov/18271278/

These statements have not been evaluated by the Food and Drug Administration. This content is for education and is not medical advice. Our products are not intended to diagnose, treat, cure or prevent any disease. Talk with a healthcare provider before starting a new supplement if you are pregnant, breastfeeding or taking medication.