Zinc is one of the 16 essential minerals that we need every day. It plays a vital role in each and every cell in our body. We call it a trace mineral, meaning that we don’t need a large amount of it. Despite this, zinc is hugely important, and has roles in immunity, metabolism, hair and skin health.
If you’re looking to maximise your nutrition each day and become the healthiest person you can be, don’t forget about this essential nutrient!
What does it do?
Zinc is involved in over 300 enzyme reactions in the body.1 More than 85% of it is found in muscle and bone.2 The body cannot store zinc, so it is important to eat it daily through the diet.
It plays roles in:2
- Wound healing
- Supporting the gastrointestinal system
- Growth and development
- DNA synthesis
- Enzyme reactions
- Gene expression
- Sense of taste and smell
- Protection against heart disease
- Healthy hair and vibrant
How is it absorbed?
Certain foods and the environment of the digestive tract can affect how much is absorbed by the body.2 Protein, found in foods such as chicken, eggs and meat improve its absorption as zinc binds to protein. As a result, it is absorbed better in animal-protein based diets rather than those richer in plant proteins. The requirement for zinc is often 50% higher in vegetarians who have major protein staples of grains and legumes.3
There are many forms of zinc supplements that may influence its absorption. Some of these include zinc gluconate, zinc acetate and zinc sulphate.
How much do I need each day?2
Where is it found:
Zinc can be found both in plant and animal foods. Some foods such as flour, cereals or snack bars which don’t naturally contain this nutrient are often fortified. This means they have zinc added into their ingredients. The bioavailability (amount the body can absorb) of zinc from grain and plant foods is lower than that of animal foods. Despite this, these plant-based foods are still a good source of this essential nutrient.
Studies show that zinc has a multitude of health benefits:
- Boosting Immunity
It is essential for maintaining a strong immune system. Zinc is required for immune cell functioning and signalling, meaning that deficiency can lead to poor immunity. Some studies indicate that those with lower levels may have an increased risk of getting pneumonia or other infections.4,5
2. Wound healing
Zinc is essential for maintaining healthy skin and wound healing. The skin holds a large 5% of the body’s total content of zinc.6
Studies have shown that those with chronic leg ulcers have low levels in their blood. They are often treated with zinc supplementation to improve this.7
3. Preventing the common cold
Emerging research indicates that zinc may be beneficial in reducing the duration of the common cold. Evidence indicates that if 75mg supplements are taken within 24 hours of the onset of a cold, this can help shorten the duration of cold symptoms.8
4. Age-related macular degeneration:
Research suggests that oral zinc may slow the progression of age-related macular degeneration (AMD) and be protective against vision loss and blindness.9 One study of 72 AMD patients who had a dietary supplement of 50mg each day slowed the progression of the condition.9,10
5. Reducing diarrhoea:
Deficiency can cause changes to immune response. It is thought that this can contribute to an increased risk of infections, especially those which cause diarrhoea. Studies show that oral supplementation can reduce the symptoms of diarrhoea in children with low levels of zinc.11,12
Who is at risk of deficiency?
When you are unable to eat enough zinc through the diet, the body increases its ability to absorb it from the digestive tract and reduces how much is lost through urine.2 Risk factors for having lower blood levels include; stress, infection or trauma.2
Signs of mild deficiency include:
- Impaired growth
- Poor pregnancy outcomes
- Impaired immunity
Severe deficiency can cause:
- Alopecia (hair loss)
- Delayed sexual development
- Erectile dysfunction
- Eye and skin lesions
- Impaired appetite
Who is at risk of deficiency:
Most people can meet their requirements of zinc through their diet. However, some groups of people are at higher risk of being unable to meet their daily needs.
- People with gastrointestinal diseases or surgeries.
Bowel diseases such as Ulcerative Colitis and Crohn's Disease can decrease the amount absorbed and increase the amount that leaves the body via the kidneys. A similar result is seen after gastrointestinal surgery including weight loss surgery such as the gastric bypass. Diseases such as chronic liver or kidney disease, diabetes and chronic diarrhoea can also lead to deficiency.13
- Those following a vegetarian diet:
Vegetarians require approximately 50% more of the recommended daily intake for zinc than non-vegetarians.3 This is due to many vegetarian protein sources containing phytates which bind to zinc and stop its absorption.14,15 To improve the absorption from these foods, it is wise to soak beans grains and seeds in water for several hours before cooking.14
The consumption of alcohol decreases the absorption of zinc through the intestines and increases the amount that leaves through urine. In addition to this, the variety and amount of food consumed by many alcoholics is limited, leading to poor intake through food.16,17
Studies show that the amount of zinc eaten by elderly people often does not meet their requirements.18 In addition to this, there is some evidence to suggest that absorption decreases with age.18
Should I supplement?
Zinc is present in several plant and animal foods and if you are eating a varied diet, you likely may be able to meet your needs.
It is important to understand the side-effects of supplementation when deciding if it is right for you. Excessive zinc intake and long term supplementation can also interact with copper absorption. In some cases, it can reduce blood copper levels and cause deficiency. It is also advised to avoid using zinc-containing intranasal products as they may cause loss of sense of taste and smell.
Despite this, zinc has a variety of health benefits and can reduce the risk of many conditions. If you are in an at-risk group or unable to eat zinc-rich foods it may be worthwhile to consider our Vitable Zinc supplement, you can check it out here.
Always speak with a qualified health professional before commencing any supplementation.
- McCall, K., Huang, C. and Fierke, C. (2000). Function and Mechanism of Zinc Metalloenzymes. The Journal of Nutrition, 130(5), pp.1437S-1446S.
- Nrv.gov.au. (2019). Zinc | Nutrient Reference Values. [online] Available at: https://www.nrv.gov.au/nutrients/zinc
- Saunders, A., Craig, W. and Baines, S. (2012). Zinc and vegetarian diets. The Medical Journal of Australia, 1(2), pp.17-21.
- Meydani, S., Barnett, J., Dallal, G., Fine, B., Jacques, P., Leka, L. and Hamer, D. (2007). Serum zinc and pneumonia in nursing home elderly. The American Journal of Clinical Nutrition, 86(4), pp.1167-1173.
- Brooks, W., Santosham, M., Naheed, A., Goswami, D., Wahed, M., Diener-West, M., Faruque, A. and Black, R. (2005). Effect of weekly zinc supplements on incidence of pneumonia and diarrhoea in children younger than 2 years in an urban, low-income population in Bangladesh: randomised controlled trial. The Lancet, 366(9490), pp.999-1004.
- Lin, P., Sermersheim, M., Li, H., Lee, P., Steinberg, S. and Ma, J. (2017). Zinc in Wound Healing Modulation. Nutrients, 10(1), p.16.
- Wilkinson, E. and Hawke, C. (1998). Does Oral Zinc Aid the Healing of Chronic Leg Ulcers?. Archives of Dermatology, 134(12).
- Singh, M. and Das, R. (2013). Zinc for the common cold. Cochrane Database of Systematic Reviews.
- Smailhodzic, D., van Asten, F., Blom, A., Mohlin, F., den Hollander, A., van de Ven, J., van Huet, R., Groenewoud, J., Tian, Y., Berendschot, T., Lechanteur, Y., Fauser, S., de Bruijn, C., Daha, M., van der Wilt, G., Hoyng, C. and Klevering, B. (2014). Zinc Supplementation Inhibits Complement Activation in Age-Related Macular Degeneration. PLoS ONE, 9(11), p.e112682.
- Vishwanathan, R., Chung, M. and Johnson, E. (2013). A Systematic Review on Zinc for the Prevention and Treatment of Age-Related Macular Degeneration. Investigative Opthalmology & Visual Science, 54(6), p.3985.
- Black, R. (1998). Therapeutic and preventive effects of zinc on serious childhood infectious diseases in developing countries. The American Journal of Clinical Nutrition, 68(2), pp.476S-479S.
- Wintergerst, E., Maggini, S. and Hornig, D. (2007). Contribution of Selected Vitamins and Trace Elements to Immune Function. Annals of Nutrition and Metabolism, 51(4), pp.301-323.
- Prasad, A. (2002). Zinc deficiency in patients with sickle cell disease. The American Journal of Clinical Nutrition, 75(2), pp.181-182.
- Ncbi.nlm.nih.gov. (2019). Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets. - PubMed - NCBI. [online] Available at: https://www.ncbi.nlm.nih.gov/pubmed/12778049/
- Hunt, J. (2003). Bioavailability of iron, zinc, and other trace minerals from vegetarian diets. The American Journal of Clinical Nutrition, 78(3), pp.633S-639S.
- Menzano, E. and Carlen, P. (1994). Zinc Deficiency and Corticosteroids in the Pathogenesis of Alcoholic Brain Dysfunction-A Review. Alcoholism: Clinical and Experimental Research, 18(4), pp.895-901.
- Navarro, S., Valderrama, R., To-Figueras, J., Giménez, A., Lopez, J., Campo, E., Fernandez-Cruz, L., Ros, E., Caballeria, J. and Pares, A. (1994). Role of Zinc in the Process of Pancreatic Fibrosis in Chronic Alcoholic Pancreatitis. Pancreas, 9(2), pp.270-274.Andriollo-Sanchez, M., Hininger-Favier, I., Meunier, N., Toti, E., Zaccaria, M., Brandolini-Bunlon, M., Polito, A., O'Connor, J., Ferry, M., Coudray, C. and Roussel, A. (2005). Zinc intake and status in middle-aged and older European subjects: the ZENITH study. European Journal of Clinical Nutrition, 59(S2), pp.S37-S41.