What and Where is Zinc?
Zinc is the second most abundant trace metal in the human body after iron, and is a crucial element of protein structure and function. (1) The human body does not have specialised storage for zinc, so we must meet a daily requirement through diet or supplementation in order to maintain adequate levels. (2) Foods that provide good levels of zinc include oysters, red meat, poultry, beans, nuts, crab, lobster, whole grains, fortified breakfast cereals and dairy products. (3)
Zinc Inadequacy
Globally, low zinc status is quite common, at around 17-20%, however the majority of these cases are in low socioeconomic countries. (1) Inadequate zinc is less common in high-income countries, though certain populations are more at risk, including the elderly, vegetarians/vegans, individuals with chronic disease. (1, 4, 5)
Zinc and the Immune System
Zinc plays an important role in cellular respiration, immune functions, protein synthesis, wound healing, DNA synthesis and cell division. (2) The immune system is especially responsive to alterations in zinc levels, with zinc homeostasis being tightly regulated both systematically and intracellularly. (1, 5) This strict regulation of zinc levels is indicative of the essential role that zinc plays in human health. (1)
A insufficiency of zinc effects all aspects of the immune system and demonstrates that availability of zinc is crucial for the proper development and function of the immune system. (2) Zinc deficiency can lead to reduced numbers of T and B lymphocytes in both the thymus and the bone marrow, resulting in an escalated vulnerability to infection and a deterioration of the body’s defences. (5)
The strongest effect that zinc exerts on the immune system is through Th1 and Th2 lymphocytes. With a reduced zinc level in the cell, the balance between Th1 and Th2 cells is disturbed. (5) This has an important impact on proper immune response because Th1 and Th2 lymphocytes perform different functions, that is, immunity against intracellular as opposed to extracellular pathogens. (5)
Zinc supplementation
Zinc helps to support immune system health, maintain immune system function and cognitive function.
Zinc oxide is one of the most poorly absorbed form of zinc. I'm Nutrients uses zinc citrate dihydrate.
Due to zinc’s importance in immune system function, it is imperative that appropriate zinc levels are reached and maintained, and can be done so through dietary intake, or a good quality supplement.
References
1. Read SA, Obeid S, Ahlenstiel C, Ahlenstiel G. The Role of Zinc in **** Immunity. Advances in nutrition (Bethesda, Md). 2019;10(4):696-710.
2. Bonaventura P, Benedetti G, Albarède F, Miossec P. Zinc and its role in immunity and inflammation. *** reviews. 2015;14(4):277-85.
3. National Institutes of Health. Zinc Fact Sheet for Health Professionals [Internet]. 2020 [cited July 15 2020]. Available from: https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/#:~:text=Oysters%20contain%20more%20zinc%20per,products%20%5B2%2C11%5D.
4. Villagomez A, Ramtekkar U. Iron, Magnesium, Vitamin D, and Zinc Deficiencies in Children Presenting with Symptoms of *****. Children (Basel, Switzerland). 2014;1(3):261-79.
5. Skrajnowska D, Bobrowska-Korczak B. Role of Zinc in Immune System and **** Defense Mechanisms. Nutrients. 2019;11(10).
Written By Brittany Darling
NUTRITIONIST (BHSC), WESTERN HERBAL MEDICINE (ADV DIP),
CERT. PAEDIATRIC NUTRITION