Zinc is one of the vital trace minerals the body needs to sustain great health. Because the body isn’t able to make zinc, we can only obtain it through food or dietary supplements.
The body needs zinc for many biological functions. First, it works like a catalyst for more than 100 different enzymes and DNA transcription[i]. Without enough zinc, the body will not be able to develop properly, heal properly or ward off infection.[ii]
Approximately 2 grams to 4 grams of zinc are spread through the body, mainly in the prostate gland, eyes, kidneys, liver, brain, muscles, and bones. To make sure you sustain that level, you need to consume foods rich in zinc, including nuts, dairy, eggs, poultry, shellfish, fish, and meat.[iii]
Zinc is important for human development and boosting the immune system. It doesn’t just help prevent both common and uncommon diseases, but it can also treat different health conditions. Following are some health benefits you should know about.
Zinc is responsible for the activation of white blood cells known as T-lymphocyte. The T-Cells play a major role in the body’s immune defense. Some of the T cells neutralize pathogens such as fungi, viruses, or bacteria.[xi]
Zinc deficiency impairs the immune system and leaves a person vulnerable to diseases that the body could have otherwise neutralized. Zinc supplementation might help support your immune response and ultimately shorten the duration of common colds.[xii]
Zinc plays a major role in maintaining the structure and integrity of the skin. Zinc deficiency manifests itself with skin problems such as slow wound healing, ulcers, and even lesions.[xiii]
Although zinc supplements might help curb certain skin diseases, topical zinc oxide might be used to speed up wound healing or treat conditions such as herpes simplex infections, diaper rash, ulcers, and acne.[xiv]
Worldwide, according to a study by the University of Colorado School of medicine, more than 500,000 deaths in children are associated with zinc deficiency.[xv] Even mild deficiency in children might cause increased weakness to infections and growth delays.
In early childhood, zinc deficiency might lead to behavioral problems (depression, lethargy, and irritability), motor delays, cognitive delays, and short stature.[xvi]
Moderate zinc deficiency could interfere with food absorption in the small intestines. This means your body will miss out on many essential nutrients.
Also, diarrhea is a characteristic symptom of zinc deficiency and could be very devastating in toddlers and infants. According to WHO (World Health Organization), taking zinc supplements for 10 to 14 days can treat diarrhea in children and prevent recurrence.[xvii]
While zinc deficiency is pretty rare, it can happen to individuals with a rare genetic mutation, alcohol addicts, people taking immune-suppressing medications, and breastfeeding newborns whose mothers do not have enough zinc.
Signs of zinc deficiency include weakened development and growth, behavior issues, impaired wound healing, chronic diarrhea, skin rashes, and tardy sexual maturity .[iv]
Mild forms of zinc deficiency are very common, particularly amongst children in developing countries.[v] Studies show about 2 billion people worldwide are zinc deficient because of a lack of enough dietary intake.[vi]
Because zinc deficiency is known to impair the immune system, increasing your chances of infections, zinc deficiency is estimated to cause more than 450,000 deaths among children less than five years.[vii]
People who might be at risk of zinc deficiency include:[viii]
- Those who drink excess alcohol
- Individuals with chronic kidney disease
- Malnourished people, including those with bulimia or anorexia
- Individuals with sickle cell anemia
- Older infants
- Breastfeeding and pregnant women
- Vegans and vegetarians
Signs of mild zinc deficiency include:[ix]
- Impaired wound healing
- Fertility issues
- Dry skin
- Mood disturbances
- Decreased appetite
- Decreased immunity
Zinc deficiency might be hard to detect through laboratory tests mainly because of the body’s regulation of zinc levels. So, you might be deficient even when the tests show normal levels.
Health providers consider external risk factors like genetics and poor dietary intake, and blood results during the determination of whether you really need supplements.[x]
Possible Side Effects
Zinc has numerous health benefits, but taking too much can be very harmful. Essentially, consuming more than 40 mg/day of zinc supplements might not be safe for you in the long term. At higher doses, zinc might cause metallic taste, cramps, vomiting, and diarrhea. Furthermore, excessive consumption of zinc might block copper absorption resulting in neurological and anemia problems.[xviii]
When applied to broken skin, zinc might cause tingling sensations, itching, and burning. Higher doses more than the recommended amounts could cause fatigue, stomach pain, coughing, fever, and other health problems.
Furthermore, taking over 100mg of supplemental zinc or taking zinc supplements for more than ten years increases the risks of prostate cancer. Also, there are concerns that taking excess multivitamins plus a different zinc supplement doubles your chances of dying from certain types of cancer especially prostrates cancer. Taking more than 450 mg of zinc every day might cause problems with blood iron. A single dose of 10 – 30 grams of zinc might be fatal.
Zinc isn’t safe when inhaled through your nose because it might lead to loss of smell. In 2009, the US FDA (Food and drug administration) advised people against using certain nose sprays (containing zinc) after receiving numerous reports of people losing smell. Overall, you should not use nose sprays that contain zinc.
Dosage And Preparation
The RDA) Recommended daily allowance of zinc vary by age, gender, and pregnancy status.[xix] With regards to supplementation, you should know the tolerable upper intake you must take from different sources per day. For zinc, the tolerable upper intake is 40 milligrams per day.
The most appropriate use of zinc eye drops, creams, or ointments varies by the product’s strength. Make sure you use the products you have as directed by carefully checking through the prescription information on the label or package insert. If you aren’t sure what some instructions mean, speak with a pharmacist or doctor.
Ways To Get Your Zinc
You can get your zinc from food sources or supplements. Without question, real food is the best source of zinc. This is because most minerals work best if taken alongside other nutrients. Moreover, with real food, you’ll also be taking additional nutrients. However, with zinc supplements, you don’t get anything else besides zinc.
Foods Rich In Zinc
Many plant and animal foods are naturally high in zinc. This makes it easy for many people to eat enough amounts. These include sweet potatoes, potatoes, whole grains, eggs, cheese, nuts, seeds, legumes, shellfish, pork, lamb, and beef. Foods high in zinc include:
- Dairy products – cheese, yogurt, and milk
- Seeds and nuts – hemp seeds, cashews, pumpkin seeds, and more
- Legumes – kidney beans, black beans, lentils, chickpeas
- Fish – sole, salmon, sardines, and flounder
- Poultry – Chicken and turkey
- Meat – bison, lamb, pork, and beef
- Shellfish – Clams, lobster, mussels, crab, and oysters
- Certain vegetables – beet greens, asparagus, peas, kale, and mushrooms
- Whole grains – brown rice, quinoa, and oats
Animal products like shellfish and meat contain higher amounts of zinc in the form that the body absorbs quickly. It’s also important to note that zinc found in plant-based sources such as whole grains and legumes is absorbed less efficiently, mainly because of other plant-based substances that hinder absorption. Although most foods are naturally higher in zinc, specific foods like baking flours, snack bars, and cereals are also fortified with zinc.
Zinc supplements are available in liquid form, ointments, creams, tablets, and capsules. Adults aged over 19 years looking to start taking zinc supplements should be careful and only eat no more than 40 milligrams every day. Too much zinc might cause a myriad of health problems.
If you choose to take zinc supplements, only choose those rigorously tested and certified by renowned certifying agencies such as the U.S. Pharmacopeia. You should avoid expired supplements, topical ointments, or eye drops.
Zinc toxicity occurs with higher doses of zinc supplements. You should consult a health provider if you experience any symptoms of toxicity, including diarrhea, cramps, pain, vomiting, and nausea.
What is the main benefit of zinc?
What food is high in zinc?
How much zinc should you take?
Who should not take zinc supplements?
Can zinc cause diarrhea?
How does zinc help the body?
- [i] Zastrow ML, Pecoraro VL. Designing hydrolytic zinc metalloenzymes. Biochemistry. 2014 Feb 18;53(6):957-78. doi: 10.1021/bi4016617. Epub 2014 Feb 7. PMID: 24506795; PMCID: PMC3985962.
- [ii] National Institutes of Health. Office of Dietary Supplements. Zinc Fact Sheet for Health Professionals. Updated March 6, 2020.
- [iii] National Institutes of Health. Office of Dietary Supplements. Zinc Fact Sheet for Health Professionals. Updated March 6, 2020.
- [iv] Fallah A, Mohammad-Hasani A, Colagar AH. Zinc is an Essential Element for Male Fertility: A Review of Zn Roles in Men’s Health, Germination, Sperm Quality, and Fertilization. J Reprod Infertil. 2018;19(2):69‐81.
- [v] Nistor, N., Ciontu, L., Frasinariu, O. E., Lupu, V. V., Ignat, A., & Streanga, V. (2016). Acrodermatitis Enteropathica: A Case Report. Medicine, 95(20), e3553. https://doi.org/10.1097/MD.0000000000003553
- [vi] Jurowski, K., Szewczyk, B., Nowak, G., & Piekoszewski, W. (2014). Biological consequences of zinc deficiency in the pathomechanisms of selected diseases. Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry, 19(7), 1069–1079. https://doi.org/10.1007/s00775-014-1139-0
- [vii] Fischer Walker CL, Ezzati M, Black RE. Global and regional child mortality and burden of disease attributable to zinc deficiency. Eur J Clin Nutr. 2009 May;63(5):591-7. doi: 10.1038/ejcn.2008.9. Epub 2008 Feb 13. PMID: 18270521
- [viii] Kumssa, D. B., Joy, E. J., Ander, E. L., Watts, M. J., Young, S. D., Walker, S., & Broadley, M. R. (2015). Dietary calcium and zinc deficiency risks are decreasing but remain prevalent. Scientific reports, 5, 10974.
- [ix] Saper, R. B., & Rash, R. (2009). Zinc: an essential micronutrient. American family physician, 79(9), 768–772.Saper, R. B., & Rash, R. (2009). Zinc: an essential micronutrient. American family physician, 79(9), 768–772.
- [x] Wieringa, F. T., Dijkhuizen, M. A., Fiorentino, M., Laillou, A., & Berger, J. (2015). Determination of zinc status in humans: which indicator should we use?. Nutrients, 7(5), 3252–3263.
- [xi] Wessels I, Maywald M, Rink L. Zinc as a Gatekeeper of Immune Function. Nutrients. 2017;9(12):1286. doi:10.3390/nu9121286
- [xii] Mousa HA. Prevention and Treatment of Influenza, Influenza-Like Illness, and Common Cold by Herbal, Complementary, and Natural Therapies. J Evid Based Complementary Altern Med. 2017;22(1):166-174. doi:10.1177/2156587216641831
- [xiii] Ogawa Y, Kinoshita M, Shimada S, Kawamura T. Zinc and Skin Disorders. Nutrients. 2018;10(2):199. doi:10.3390/nu10020199
- [xiv] Gupta M, Mahajan VK, Mehta KS, Chauhan PS. Zinc Therapy in Dermatology: A Review. Dermatol Res Pract. 2014;2014:709152. doi:10.1155/2014/709152
- [xv] Krebs NF, Miller LV, Hambidge KM. Zinc deficiency in infants and children: a review of its complex and synergistic interactions. Paediatr Int Child Health. 2014;34(4):279-288. doi:10.1179/2046905514Y.0000000151
- [xvi] Gogia S, Sachdev HS. Zinc supplementation for mental and motor development in children. Cochrane Database Syst Rev. 2012;12:CD007991. doi:10.1002/14651858.CD007991.pub2
- [xvii] Khan WU, Sellen DW. World Health Organization. Zinc supplementation in the management of diarrhoea. 2011.
- [xviii] National Institutes of Health. Office of Dietary Supplements. Zinc Fact Sheet for Health Professionals. Updated March 6, 2020.
- [xix] National Institutes of Health. Office of Dietary Supplements. Zinc Fact Sheet for Health Professionals. Updated March 6, 2020.