Zinc is an essential mineral that helps your metabolism, digestion, and immune system. Your body can’t produce zinc, so you have to get it from your diet. Good sources of zinc include meat, dairy, shellfish, legumes, and nuts.
- What is zinc?
- What does your body use zinc for?
- How does zinc support your immune system?
- Can zinc help prevent colds?
- What are the symptoms of zinc deficiency?
- Causes of zinc deficiency
- How much zinc does your body need?
- What foods are good sources of zinc?
What is zinc?
Zinc is an essential mineral that helps your body carry out lots of important functions. Because your body can’t produce zinc, you must get it from your diet.
What does your body use zinc for?
Studies show that it’s essential for creating over 100 enzymes. The enzymes then play an important role in:
- skin health
- breaking down nutrients — like carbohydrates
- wound healing
- supporting your immune system
How does zinc support your immune system?
Zinc activates enzymes that help fight infections — these enzymes break down proteins in bacteria and viruses, stopping their spread. If your body doesn’t have enough zinc, your response to infections can be slower and weaker.
Can zinc help prevent colds?
Some research indicates that taking zinc within 24 hours of the start of cold symptoms might reduce the duration and severity of symptoms. This is why you might notice that it’s often found in cold lozenges and remedies. But it’s unclear what dose and form are the best to take, and taking too much can be harmful. It’s a good idea to speak to your pharmacist or GP before taking a supplement.
What are the symptoms of zinc deficiency?
Zinc is essential for the creation of new cells. So if you’re zinc deficient, you might notice the following symptoms:
- weight loss
- a decrease in sense of smell and taste
- wounds that take longer to heal
Causes of zinc deficiency
You should be able to get all the zinc you need from a balanced and varied diet. But certain factors might increase your risk of zinc deficiency, like if you:
- suffer from a gastrointestinal disorder — like coeliac disease or Crohn’s disease
- follow a vegan diet — check you’re getting enough using the free dietary self-assessment app from The Vegan Society, VNutrition
How much zinc does your body need?
The NHS recommends that the amount of zinc your body needs is about:
- 9.5 mg a day for males (aged 19 to 64 years)
- 7 mg a day for females
There’s no known benefit to having more zinc than the recommended amount. In fact, too much zinc can also have possible side effects — like trouble absorbing copper, nausea, loss of appetite, and temporary taste issues. Don't take more than 25mg of zinc supplements a day unless advised to by your doctor.
What foods are good sources of zinc?
Foods that are rich in zinc include:
- shellfish — oysters, crab, mussels, lobster, and clams
- meat — beef, pork, lamb and bison
- poultry — turkey and chicken
- fish — flounder, sardines, salmon, and sole
- legumes — chickpeas, lentils, black beans, kidney beans, and so on
- nuts and seeds — pumpkin seeds, cashews, hemp seeds, and so on
- dairy products — milk, yoghurt, and cheese
- whole grains — oats, quinoa, brown rice, etc.
- certain vegetables — mushrooms, peas, asparagus, and leafy greens
It’s worth noting that plant chemicals called phytates (phytic acid) can block the absorption of zinc. These are found in nutritious foods like spinach, beets, nuts, seeds, legumes, and grains. In well-balanced diets, this is rarely a concern. But you can reduce the phytic acid content of food through several preparation methods — like soaking, sprouting, and fermenting.
Hemilä, H. (2017). Zinc lozenges and the common cold: a meta-analysis comparing zinc acetate and zinc gluconate, and the role of zinc dosage. JRSM open, 8(5), 2054270417694291.
National Health Services (2020). Vitamins and minerals. Retrieved 14 April 2020 from https://www.nhs.uk/conditions/vitamins-and-minerals/others/
National Institute of Health (2020). Office of dietary supplements. Zinc: Fact sheet for health professionals. Retrieved 16 March 2020 from https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
Prasad, A. S. (2008). Zinc in human health: effect of zinc on immune cells. Molecular medicine, 14(5), 353-357.
Wintergerst, E. S., Maggini, S., & Hornig, D. H. (2006). Immune-enhancing role of vitamin C and zinc and effect on clinical conditions. Annals of Nutrition and Metabolism, 50(2), 85-94.