Zinc
Written by Ada’s Medical Knowledge Team
Updated on
Zinc is a trace element that is present in some foods and is also available as a dietary supplement. It is important for growth, wound healing, fighting infection and making new cells and proteins. 1
Our bodies can’t store zinc so it is important that we get it every day either from our diets or as a supplement. Most people should be able to get enough zinc from their diet. Foods high in zinc include meat, shellfish, and dairy. You can read more about zinc in this article.
What is zinc?
Zinc is a trace element which helps the body to make new cells and enzymes. It plays a role in wound healing, fighting infection and making proteins. 1 Zinc is important for growth during childhood, adolescence and pregnancy.
Zinc also helps the functions of taste and smell. 2 It is important that we get zinc from either our diet or supplements everyday as the body has no way to store zinc.
What is zinc good for?
Zinc benefits the immune system. Lower zinc intake is associated with an increased risk of contracting infections. Zinc supplements may reduce symptoms of respiratory infections and shorten the length of illness. 3 More research on the role of zinc supplementation in COVID-19 infection is needed.
Studies in South-East Asia and Sub-Saharan Africa have shown that short course zinc supplementation reduces duration and severity of diarrhea in malnourished children. Short term zinc is recommended by the World Health Organisation for the treatment of acute childhood diarrhea. 2
When are zinc supplements needed?
Most people should be able to get all the zinc they need from eating a varied and balanced diet. 1 Vegetarians and vegans are most at risk of zinc deficiency.
Foods like legumes and whole grains contain phytates which impair zinc absorption. Oxalates also reduce the absorption of zinc. They’re found in leafy vegetables (such as spinach), okra, tea and nuts. 4 5
If you eat a lot of phytate and oxalate containing foods, you might need more zinc as you will absorb less of it in your intestines. Regularly consuming large amounts of alcohol can also impair zinc absorption. 2
If you have a chronic health condition you may be more at risk of zinc deficiency. Conditions which can affect zinc absorption include: 2 3
- Digestive system diseases (for example ulcerative colitis, Crohn's disease)
- Liver disease
- Kidney disease
- Sickle cell disease
- Diabetes
- Cancer.
How much zinc do I need?
The required daily amount of zinc differs for men and women, with age, pregnancy and breastfeeding: 2
- Infants (birth to 12 months): 2-3mg/day
- Children (1 to 13 years): 3-8 mg/day
- Females (>13 years): 8-9 mg/day, increased to 11-13 mg/day during pregnancy and breastfeeding
- Males (>13 years): 11 mg/day
What are the symptoms of zinc deficiency?
You could consider zinc supplements if you have zinc deficiency. You should speak to your doctor before taking zinc supplements.
The symptoms of zinc deficiency include: 2
- Impaired growth in children, adolescents and during pregnancy
- Loss of appetite
- Hair loss
- Diarrhea
- Sexual dysfunction
- Poor wound healing
- Change in sense of taste and smell
- Weight loss
- Brain fog
A lot of these symptoms are non-specific and can be associated with other health conditions. It is important to speak to a doctor if you think you might have zinc deficiency.
What types of zinc do exist?
Zinc supplements are available as zinc gluconate, zinc sulfate, and zinc acetate. 3 Zinc also has other uses. Zinc oxide is used in cosmetics. Zinc oxide cream is also available as sunscreen which reflects ultraviolet radiation. 6
Zinc chloride is used in textile processing and making chemicals. It is not meant for humans to take as a supplement. 7
What foods are high in zinc?
Foods high in zinc include meat, shellfish, dairy, nuts and breakfast cereal fortified with zinc. 1
Zinc content in milligrams per serving (mg): 2
- oysters, 3 ounces: 74 mg
- roast beef, 3 ounces: 7 mg
- pork chop, 3 ounces: 2.9 mg
- baked beans, ½ cup: 2.9 mg
- breakfast cereal, fortified with zinc, 1 serving: 2.8 mg
- pumpkin seeds, 1 ounce: 2.2 mg
- yoghurt, 8 ounces: 1.7 mg
- chickpeas, ½ cup: 1.3 mg
What side effects does zinc have?
Taking high doses of zinc supplements can reduce how much copper the body can absorb. 3 This can cause anemia and weak bones. You should not take more than 25mg of zinc supplements a day to avoid side effects. 1 You should speak to your doctor before taking zinc supplements
Zinc side effects include: 2
- Nausea
- Vomiting
- Loss of appetite
- Abdominal cramps
FAQs
Q: What does zinc do for the body?
A: Zinc is essential for wound healing, fighting infection, and growth. It helps the body to make new cells and proteins. Zinc also plays a role in our sense of taste and smell.
Q: When to take zinc?
A: Most people should be able to get enough zinc from a healthy, balanced diet. If you are vegan or vegetarian it can be harder to get enough zinc from food. Chronic health conditions can also increase the risk of zinc deficiency. 3 You should speak to a doctor before taking zinc supplements.
Q: How much zinc per day?
A: The required daily amount of zinc differs for men and women, with age, pregnancy, and breastfeeding. 2 Infants (birth to 12 months): 2-3mg/day. Children (1 to 13 years): 3-8 mg/day. Females (>13 years): 8-9 mg/day, increased to 11-13 mg/day during pregnancy and breastfeeding. Males (>13 years): 11 mg/day.
Q: When to see a doctor?
A: If you think you might have zinc deficiency you should see a doctor. You should speak to a doctor before taking zinc supplements.