Zinc 101: Uses, Dosage, Foods, Supplements, Risks, and More

Move over, vitamin C. Zinc may be the new cold fighter in town. Many studies have shown that taking a zinc supplement may help shorten the duration of the common cold, but it also plays a big part in promoting proper growth.

Zinc is considered a trace mineral, which means your body needs only a small amount of it to work properly. (1) Still, it’s important because of the role it plays in keeping you healthy. Zinc heals wounds and keeps your immune system humming and ready to take on threatening bacteria and viruses. (2) An over-the-counter zinc supplement may help reduce the duration and the severity of the common cold — as long as you take it within 24 hours of the first sign of sickness. (3)

Zinc also helps the body make protein and DNA. (2,4) “Zinc is crucial during pregnancy, infancy, and childhood because it supports proper growth and development during each of these life stages,” says Angie Kuhn, RDN, the Seattle-based director of research and development for Persona. Some studies suggest zinc may help slow the progression of macular degeneration when combined with other vitamins and antioxidants, though more research is needed. (5)

Zinc can’t be stored in the body, so you need to get your daily fix through food or a supplement. (6) It doesn’t take much to fulfill your daily quota — most Americans easily meet it through a varied diet. (2)

Here are the daily zinc requirements based on age: (2)

• 0–6 months: 2 milligrams (mg)
• 7–12 months: 3 mg
• 1–3 years: 3 mg
• 4–8 years: 5 mg
• 9–13 years: 8 mg
• 14–18 years (boys): 11 mg
• 14–18 years (girls): 9 mg
• Adult men: 11 mg
• Adult women: 8 mg
• Pregnant teens: 12 mg
• Pregnant women: 11 mg
• Breastfeeding teens: 13 mg
• Breastfeeding women: 12 mg

Zinc deficiency can occur if you don’t take in enough zinc, if the body doesn’t absorb the nutrient well, or if the mineral is lost through the gastrointestinal system. (7)

Symptoms of zinc deficiency include: (8)

• Impaired growth
• Delayed puberty
• Erectile dysfunction
• Diarrhea
• Hair loss
• Swollen tongue
• Distorted or discolored nails
• Decreased immunity

Zinc deficiency isn’t common in the United States, though there are some groups of people who are at an increased risk, including: (9)

• People with gastrointestinal issues, such as Crohn’s disease and ulcerative colitis, because zinc can be lost through the gastrointestinal tract
• People with sickle cell disease, because they may require more zinc
• Vegetarians, because they miss out on zinc-rich meat and seafood (beans and fortified cereals are two food sources of zinc that they should include)
• Pregnant women, because the growing baby requires extra zinc
• Alcoholics, because they have a decreased ability to absorb the nutrient and an increased likelihood of passing it when they go to the bathroom

Zinc is found in many foods, including meat (red meat, turkey, lamb, and chicken), seafood (oysters and crab), baked beans, and fortified breakfast cereals. (10) That may put vegetarians in a tricky spot, but all legumes — including chickpeas, lentils, and beans — are good sources of zinc, says Krista Linares, RD, a Raleigh, North Carolina–based nutritionist and the founder of Nutrition con Sabor. Kuhn adds blueberries, nuts, and whole grains to the meat-free list of zinc sources.

Not likely. “In general, people get enough zinc,” says Natalie Allen, RD, a dietitian and clinical assistant professor of dietetics at Missouri State University in Springfield. If you eat a healthy diet with lots of variety, chances are you’re already meeting your daily requirement. But if you have a zinc deficiency or are at risk of developing one, you might benefit from taking a supplement. (11) Most supplements will deliver your daily zinc quota, but if you’re treating a zinc deficiency, be sure to consult your doctor first to determine the correct dose. (12) Linares recommends a general multivitamin rather than one solely for zinc. “Many standard multivitamins contain some zinc in an amount that is generally safe,” she says.

RELATED: Can Supplements Protect Me Against COVID-19?

Zinc lozenges are cold remedies that are often combined with vitamin C, whereas zinc supplements are fitting for people with a zinc deficiency. “Zinc lozenges and nasal sprays directly interfere with the rhinovirus’s ability to breed in the moist environment of the throat or nose, so taking a lozenge or using nasal spray containing zinc gluconate and zinc acetate have been shown to have the greatest antiviral effectiveness,” says Brandi Cole, PharmD, a Knoxville, Tennessee–based pharmacist. (Rhinovirus is the most common virus that causes the common cold.) (13)

Zinc supplements are traditionally capsules that are swallowed whole, while zinc lozenges are essentially cough drops with zinc as the main active ingredient. Lozenges aren’t always well tolerated, because they’re designed to dissolve in the mouth and don’t always taste great. (14) Also keep in mind that zinc lozenges typically contain less zinc than standard zinc dietary supplements, Dr. Cole says. “So if you’re looking to increase your zinc intake to improve overall immune function long term, a dietary supplement may be the best, most effective option,” she says. To find out if a zinc supplement may be beneficial for you, consult your healthcare team.

Getting too much zinc from diet alone is rare, Allen says. “As with most vitamins and minerals, overdoing it is usually associated with supplementing, not with eating,” she says. Too much zinc could result in vomiting, cramping, and diarrhea. These signs usually show up within 10 hours of taking a supplement and should go away soon after you stop the supplements. (4) Ingesting high doses of zinc for an extended period of time can cause copper deficiency, which can lead to heart and kidney failure, liver damage, brain disease, or even death. (15,16)

The maximum intake of zinc depends on your age: (9)

• 0–6 months: 4 mg
• 7–12 months: 5 mg
• 1–3 years: 7 mg
• 4–8 years: 12 mg
• 9–13 years: 23 mg
• 14–18 years: 34 mg
• 19 and older: 40 mg

You should also be careful about your zinc intake if you’re taking quinolone or tetracycline antibiotics, penicillamine (which treats rheumatoid arthritis), or thiazide diuretics. Oral zinc while taking antibiotics or penicillamine can prevent the medications from working properly, while people taking thiazide diuretics blood pressure medications increase the chances of losing zinc in urine. (11) Zinc products that pass through the nasal passageways come with a risk of losing a sense of smell, sometimes permanently. (17)

Q: How does zinc help your body?

A: Zinc helps keep the immune system functioning properly and may help shorten the duration of the common cold. It helps promote growth and DNA and may delay the progression of macular degeneration.

Q: What are the signs of a zinc deficiency?

A: Delayed growth and puberty, diarrhea, hair loss, swollen tongue, erectile dysfunction, nail issues, and decreased immunity are all signs that you’re not getting enough zinc.

Q: When should I take zinc?

A: Most people source enough zinc through diet alone, but if you’re not getting enough or you’re at risk of a zinc deficiency, you can add a multivitamin containing zinc or a zinc supplement every day (or as recommended by your doctor).

Q: How much zinc can you take in a day?

A: Adults should limit their intake of zinc to 40 mg or less per day.

Q: What does zinc do for you sexually?

A: Low levels of zinc have been linked to erectile dysfunction and male infertility. (6,8) Zinc is normally found in semen, but if levels are too low, it could delay the development of the male reproductive system and lead to a deficiency of sex hormones. (18)