By: Pallavi Vathiar. Practicing Clinical Nutritionist, Mumbai.
“When we are supposed to protect ourselves from the virus from outside, we need to protect ourselves beginning right from within our body by strengthening the immune system.”
Importance of Boosting Immunity:
A robust and properly functioning immune system helps you go about daily life as your body’s first line of defence is its physical barriers. If viruses and bacteria manage to break through, there are specialised cells that will jump into action. Your bloodstream and key areas of your body contain white blood cells that can fight and destroy the viruses and bacteria they find. You could pick up infections and infectious diseases more easily, and the effects could be serious – even fatal.
Sometimes, our immune system can overreact and even attack your body’s own cells. This is what happens in the case of allergies like hay fever and autoimmune diseases.
Zinc and its Role in Enhancing Immunity:
Since the first discovery in an Iranian male in 1961, zinc deficiency in humans is now known to be an important malnutrition problem world-wide. It is more prevalent in areas of high cereal and low animal food consumption (1).
Zinc is a nutrient that plays many vital roles in your body. It is considered an essential nutrient, meaning that your body cannot produce or store it, hence you must obtain it through food or supplements which is naturally found in a wide variety of both plant and animal foods.
Because of its role in immune function, zinc is likewise added to some nasal sprays, lozenges, and other natural cold treatments as it is necessary for the activity of over 300 enzymes that aid in metabolism, digestion, nerve function, Sense of taste and smell and many other processes.
Zinc supplementation studies was conducted in patients who suffer from autoimmune diseases, namely rheumatoid arthritis (RA). When the effect of zinc supplementation on RA patients was investigated, it detected positive changes after zinc therapy regarding joint swelling, morning stiffness, and walking time (2).
A laboratory study in 2010 showed that zinc inhibited the activity and replication of another coronavirus, SARS-CoV which caused an outbreak in 2002 (3).
Insufficiency of Zinc:
According to the WHO, zinc deficiency is currently the fifth leading cause of mortality and morbidity in developing countries.
Zinc deficiency is characterized by growth retardation, loss of appetite, and impaired immune function. In more severe cases, zinc deficiency causes hair loss, diarrhoea, delayed sexual maturation, impotence, hypogonadism in males, eye, and skin lesions. Groups at risk of Zinc Inadequacy are listed below:
- People with gastrointestinal and other diseases.
- Pregnant and lactating women.
- Older infants who are exclusively breastfed.
- People with sickle cell disease.
- Alcoholics (4).
Studies have found that zinc deficiency weakens the immune system and hence result in delayed wound healing, particularly in the elderly with impaired nutritional status (5)(6).
A study reported a 2-y-old girl with severe acrodermatitis enteropathica (rare genetic autosomal disorder) with a lactose-deficient synthetic diet but was not showing any satisfactory response to this therapy. The serum zinc concentration was significantly decreased. They, therefore, administered oral zinc sulphate to correct this deficiency. Surprisingly, the skin lesions and gastrointestinal symptoms cleared after zinc supplementation. When zinc was inadvertently omitted from the child’s regimen, the child suffered a relapse; however, she again completely responded to oral zinc therapy (7).
Zinc Sulphate Monohydrate:
Zinc Sulphate Monohydrate (ZnSO4) is an inorganic compound and dietary supplement. As a supplement it is used to treat zinc deficiency and to prevent the condition in those at high risk.
Zinc sulphate is soluble in water and is insoluble in alcoholand it contains 23% elemental zinc.
220 mg zinc sulphate contains 50 mg zinc (8).
Recommended Dietary Allowance according to Indian Council of Medical Research (ICMR) (9).
|1 to 3 years||5 mg||5 mg|
|4 to 6 years||7 mg||7 mg|
|7 to 9 years||8 mg||8 mg|
|10 to 12 years||9 mg||9 mg|
|13 to 15 years||11 mg||11 mg|
|16 to 17 years||12 mg||12 mg|
|18 years and above||12 mg||10 mg|
|18 years and above (Pregnancy)||0||12 mg|
|18 years and above (Lactation 0 to 12 months)||0||12 mg|
Many animal and plant foods are naturally rich in zinc, making it easy for most people to consume adequate amounts.
Foods highest 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, etc.
- Nuts and seeds: Pumpkin seeds, cashews, hemp seeds, etc.
- Dairy products: Milk, yogurt and cheese
- Whole grains: Oats, quinoa, brown rice, etc.
- Certain vegetables: Mushrooms, kale, peas, asparagus and beet greens
Animal products, such as meat and shellfish, contain high amounts of zinc in a form that your body easily absorbs.
Plant-based sources like legumes and whole grains is absorbed less efficiently because of other plant compounds that inhibit absorption.
While many foods are naturally high in zinc, certain foods — such as ready-to-eat breakfast cereals, snack bars and baking flours — are fortified with zinc.
- J Res Med Sci. 2013 Feb; 18(2): 144–157. Zinc and its importance for human health: An integrative review. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3724376/
- Simkin P. A. (1976): Oral zinc sulphate in rheumatoid arthritis. Lancet, 2, 539–542. ncbi.nlm.nih.gov/pmc/articles/PMC1001021/
- Amy C. Sims (2010): Zn2+ Inhibits Coronavirus and Arterivirus RNA Polymerase Activity In Vitro and Zinc Ionophores Block the Replication of These Viruses in Cell Culture. https://doi.org/10.1371/journal.ppat.1001176. https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1001176
- Nour Zahi Gammoh and Lothar Rink et al’. 2017 Jun; 9(6): 624. Zinc in Infection and Inflammation. Doi: 10.3390/nu9060624. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5490603/
- Aging and wound healing. Ankush Gosain A, DiPietro LA. World J Surg. 2004 Mar; 28(3):321-6. https://sci-hub.tw/10.1007/s00268-003-7397-6
- Barnes PM, Moynahan EJ. Zinc deficiency in acrodermatitis enteropathica. Proc R Soc Med. 1973; 66:327–9. https://sci-hub.tw/10.3945/an.112.003210
- All about zinc sulphate monohydrate. https://pubchem.ncbi.nlm.nih.gov/compound/ZINC-sulfate-monohydrate
- Recommended Dietary Allowance. https://archive.fssai.gov.in/dam/jcr:651fb6ae-d530-4162-be1a-8bf38c3743c7/Note_Dietary_Allowance_27_02_2019.pdf