Written By: Dr. Diane Fulton

Zinc is an essential mineral for your health, so be sure you have enough zinc to keep you safe and enjoy a long life

Your body needs a variety of micronutrients and zinc is one of them. Zinc is anti-inflammatory, immunomodulatory, antioxidant, neuroprotective, cardio-protective and an infection fighter. Zinc deficiencies or lower levels of zinc in the body -- caused by poor diet, oxidative stressors in the environment, the use of statin drugs and even natural aging -- can lead to or increase your risk for a variety of health issues.

Optimal zinc levels may lower your risks for infections, cancers and heart diseases, increase your overall immunity and longevity, as well as help with inflammatory illnesses such as asthma, diabetes, neurological disorders and metabolic syndrome.

Eating your way to healthy zinc levels is easy -- just follow the chart below for common zinc-rich foods. Daily zinc values recommended are 11 milligrams (mg) for men and 8 mg for women.

ZINC-RICH FOODS (PORTION, ZINC IN MG)

Oysters (3 oz, 38.3)

Beef (3 oz, 10.2)

Lamb (3 oz, 6.9)

Baked Beans with pork and tomato sauce (1/2 cup, 6.7)

Pork (3 oz, 5.7)

Sesame Seeds (1/2 cup, 5.1)

Cashews (1/2 cup, 3.8)

Pumpkin seeds (1/2 cup, 4.5)

Peanuts (1/2 cup, 3.2)

Crabs (3 oz, 3.2)

25% Fortified Cereals/Breads (1 serving, 2.8)

Turkey (3 oz, 2.8)

Chickpeas (1/2 cup raw, 2.8)

Cocoa (1/2 cup dry, 2.7)

Chicken (3 oz, 2.6)

Almonds (1/2 cup, 2.3)

Oatmeal (1 cup, 2.3)

Cheese (1/2 cup, 2.1)

Tofu (1/2 cup raw, 2.0)

Brown Rice (1/2 cup raw, 1.9)

Whole Wheat Pasta (1/2 cup dry, 1.4)

Lentils (1/2 cup, 1.3)

Greek Yogurt (6 oz, 1.0)

Dietary Supplements (5 mg to 40 mg)

1. Zinc Deficiency

A zinc deficiency impairs the immune system resulting in increased risk of infection. In a study of 32 children admitted to the hospital with dengue viral infections, 47% had a zinc deficiency. Fever duration and length of hospital stay were longer in zinc-deficient children compared to those who had normal levels.[i]

In a study of 1,253 patients diagnosed with coronary heart disease compared to a control group of 2,288 healthy patients, decreased zinc levels were found to be an independent risk factor for coronary heart disease.[ii]

In a study of pre-high blood pressure involving 142 apparently healthy subjects (90 women and 52 men ages 20 to 60 years) , scientists showed that a zinc deficiency was associated with pre-high blood pressure markers.[iii]

In a nutrition study of 182 infants and 207 preschoolers in rural Guatemala, anemia was found in 56% of the infants and 12% of preschoolers. The rates of iron and zinc deficiencies were 83%/75% and 63%/18% respectively for the two groups. Due to micronutrient deficiencies among these children, zinc and iron supplementation are beneficial to reduce anemia in rural areas.[iv]

In a comprehensive research review, both in vitro and in vivo studies have shown an association between a zinc deficiency and increased risk of neurological disorders.[v]

In a seizure-induced rat model, a zinc-deficient diet for four weeks aggravated the long-term adverse effects of developmental seizures but a regimen of zinc supplementation for four weeks significantly improved damage-related changes to the neuronal membrane and cognition.[vi]

2. Oxidative Stress

Certain environmental issues -- pollution, alcohol, tobacco smoke, heavy metals, transition metals, industrial solvents, pesticides, certain drugs like halothane, paracetamol and radiation -- can induce imbalances in the body creating free radical-induced oxidative stress. Oxidative stress has been linked to Type 2 diabetes, neurodegenerative disorders, cardiovascular diseases, respiratory diseases, cataract development, rheumatoid arthritis and various cancers.[vii]

Adequate levels of zinc, since it is both an antioxidant and anti-inflammatory nutrient, are important to effectively reduce oxidative stress and inflammation, which, in turn, strengthens your immune system.[viii]

Excessive exposure to pesticides induces oxidative stress and has been linked to alterations in the lipid profile. In a study of 40 pesticide sprayers, supplementation with zinc significantly improved their oxidative stress markers and their lipid status.[ix]

In a clinical study of 105 diabetics, a supplement -- 600 mg of α-lipoic acid, 165 mg of L-carnosin, 7.5 mg of zinc and B vitamins -- was compared to a placebo. The food supplement with zinc improved glycemic control, lipid profile and antioxidative stress markers.[x]

Supplementation with zinc (30 mg), vitamin A (25,000 IU) and magnesium (250 mg) daily for 10 weeks in the treated group of 86 hypothyroid patients helped to improve thyroid function, oxidative stress and inflammatory markers.[xi]

3. Aging and Aging Skin

Aging is a natural occurrence over time with both biological and physical changes that can lead to disease, but enhancing nutrients such as zinc, selenium and niacin can help you age healthier and live longer.

Experiments performed "in vitro" on human cells and "in vivo" on zinc-deficient mice showed that zinc supplementation is important for immune efficiency, metabolic homeostasis and antioxidant activity. Niacin helped with DNA repair and maintaining genomic stability. Selenium provoked zinc release by metallothioneins.[xii]

Zinc supplementation improved the immune response in healthy elderly patients enrolled in a 48-day study by positively impacting the stress response during aging and acted as an antiaging mechanism in the immune system.[xiii]

In an aging mouse model, age-related zinc loss was found to contribute to T cell dysfunction and chronic inflammation. This immune dysfunction in the elderly is exacerbated by inadequate zinc dietary intake and improved with zinc supplementation.[xiv]

In a comprehensive review of research, supplementation with both selenium and zinc have antioxidant effects in the elderly by improving the decline of immune and cognitive functions and the pathogenesis of age-related disorders such as Type 2 diabetes.[xv]

A novel dietary supplement that included extracts from zinc, chamomile, grape seed, white tea, tomato and soy, fish protein polysaccharides, vitamins C and E provided improved condition, structure and firmness of aging skin in a six-month study of 80 post-menopausal women.[xvi]

4. Coronavirus Infection

In an observational study of 269 patients in a hospital intensive care unit (ICU), critically ill patients infected by coronavirus with severe acute respiratory distress syndrome were found to have a higher prevalence of low serum zinc levels.[xvii]

In a case versus control study with 30 controls and 90 cases of patients infected with coronavirus, the mean zinc level of cases was significantly lower than in controls. Among the patients, those with lower zinc levels had nearly double the risk of becoming hypoxic -- oxygen deficient -- and eventually needing oxygen support.[xviii]

5. Inflammation and Neuroinflammation

Foods and nutrients can be healing for your body. For example, vitamin D, vitamin E, zinc and probiotics have been shown to reduce infections while green tea, vitamin D and n-3 polyunsaturated fatty acids (PUFAs) help fight autoimmune and inflammatory disorders.[xix]

In a systematic review of the role of nutrition to counteract inflammatory and immune system responses in respiratory viruses such as rhinovirus, coronavirus, the flu and adenovirus, researchers recommended a predominantly anti-inflammatory diet that included turmeric, ginger, garlic, onions, saffron, vitamin C, vitamin D, zinc and omega-3 to reduce infection symptoms and duration.[xx]

In a study of 56 children with acute shinellosis -- a severe bacterial infection associated with diarrhea and malnutrition, a 14-day course of 20 mg of zinc increased both inflammatory and immunity responses.[xxi]

Zinc homeostasis has been found to be crucial for your innate immune system, especially for maintaining the function of macrophages. Dysregulated zinc in macrophages causes impaired phagocytosis -- your phagocyte cells can't consume and destroy pathogens (like infections and bacteria) and infected cells -- and an abnormal inflammatory response.[xxii]

In an in-vitro study of mice induced with neuroinflammation, zinc supplementation inhibited neural inflammatory responses mediated by microglia cells via upregulation of zinc-finger A20 and could be the underlying mechanism of the antidepressive effects of zinc found in previous studies.[xxiii]

6. Macular Degeneration

The eye has an unusually high concentration of zinc compared to other tissues. Review of research suggested that ocular zinc concentrations decrease with age, especially in the context of age-related diseases.[xxiv]

Some research has shown that 8 to 11 mg of zinc supplements can slow the progression of age-related macular degeneration (AMD) -- an eye disease caused by aging.[xxv]

In a study of human donor eyes, reduced retinal pigment epithelium, choroid complex zinc and copper levels in AMD eyes were found. Zinc plus copper supplements reduced the risk of AMD progression and researchers concluded that metal homeostasis plays a role in AMD and retinal health.[xxvi]

Zinc monocysteine supplement of 25 mg twice daily was well tolerated and associated with improved macular function in comparison to a placebo in persons with dry AMD.[xxvii] Twenty-seven patients with nonadvanced AMD were divided into two age-similar groups: 15 patients had oral treatment of vitamin C (180 mg), vitamin E (30 mg), zinc (22.5 mg), copper (1 mg), lutein (10 mg), zeaxanthin (1 mg) and astaxanthin (4 mg) daily for 12 months and 12 patients had no dietary supplementation during the same period.

In nonadvanced AMD eyes, a selective dysfunction in the central retina (0 degrees to 5 degrees) can be improved with the carotenoids and antioxidant treatment but not in the more peripheral (5 to 20 degrees) retinal areas.[xxviii]

7. Low Testosterone

A deficiency in zinc has long been associated with testicular suppression, including suppression of testosterone levels.[xxix]

Dietary zinc intake was restricted -- 2.7 to 5.0 mg daily -- for 24 to 40 weeks in five male volunteers with a mean age of 57 years old. The baseline sperm concentration and total sperm count per ejaculate in all five subjects dropped significantly after zinc restriction and returned to normal six to 12 months after zinc supplementation, showing zinc's effects on testicular function.[xxx]

Zinc supplementation of 40 marginally zinc-deficient normal elderly men for six months resulted in nearly doubling of testosterone.[xxxi] Zinc therapy also improved sexual competence of male rats in a dose-dependent manner over a period of two weeks.[xxxii]

8. Pneumonia

Your immune system needs multiple specific micronutrients, including vitamins A, D, C, E, B6, and B12, folate, zinc, iron, copper and selenium, which play vital, often synergistic, roles at every stage of the immune response. Micronutrients with the strongest evidence for immune support include vitamins C and D and zinc, and additional supplementation is even more essential when the person is susceptible to stress, pollution or infections.[xxxiii]

In a study of 998 elderly from 33 nursing homes, subjects with normal final serum zinc concentrations after supplementation treatment had a lower incidence of pneumonia, almost 50% fewer new antibiotic prescriptions, a shorter duration of pneumonia, fewer days of antibiotic use and a reduction in all-cause mortality.[xxxiv]

In review of six randomized trials including 2,216 patients with severe pneumonia, giving zinc as an adjunct to the treatment of severe pneumonia was effective in reducing the mortality of the disease.[xxxv]

9. Cancers (All)

The anticancer effect of zinc is most often associated with its antioxidant properties, the influence of zinc on the immune system, transcription factors, cell differentiation and proliferation, DNA and RNA synthesis and repair, enzyme activation or inhibition, the regulation of cellular signaling and the stabilization of the cell structure and membranes.[xxxvi]

Higher levels of zinc decreased cancer risk in 12 types of cancers including bladder, breast, colon, esophageal, gastric, rectal, Hodgkin's lymphoma, laryngeal, nasopharyngeal, oral, skin and vulva.[xxxvii]

In a review of 201 esophageal squamous cell carcinoma (ESCC) cases among 47,405 subjects enlisted in a nutritional study, higher intakes of calcium and zinc were associated with a lower risk of ESCC.[xxxviii]

In a zinc-deficient rat model, researchers found that zinc regulated an inflammatory pathway in esophageal cancer, which can be used as prevention and therapy for this type of cancer.[xxxix]

In a mammal study of macrophage cells, researchers discovered an immunostimulatory role for an iodine substituted zinc phtgalocyanine derivative, which produced significant changes in pro-inflammatory cytokine production levels[xl] and is proving effective for treating cervical,[xli] oral, head, neck and ocular cancers.[xlii]

10. Asthma

In a meta-analysis, lower circulating zinc and selenium levels were associated with an increased risk of asthma.[xliii]

In a study of 60 asthmatics and 30 apparently healthy volunteers, serum zinc levels were significantly lower in atopic asthmatics -- their asthma is triggered by external allergens, such as dust, ozone, antibiotics, animals, pollen and food -- than non-atopic asthmatics and healthy controls.[xliv]

In research of 76 asthmatic children, 72 participants had high oxidative stress, all participants had a zinc deficiency and nearly 40% of participants had a vitamin C deficiency. Vitamin C deficiency was associated with severe asthma and airway obstruction. Supplementation with vitamin C and zinc positively correlated with improved asthma relief and pulmonary functions, respectively.[xlv]

Powerful Reasons to Optimize Your Zinc Intake

With at least 10 compelling reasons, it makes sense to eat more zinc-rich foods such as oysters, crabs, meats, seeds, nuts, lentils/beans, oatmeal, cheese and yogurt. In addition to lowering your risk for serious diseases like cancers, heart attacks, asthma, brain disorders, diabetes, pneumonia and viral infections, zinc can also improve skin quality, testosterone, eye health and the ability to age better.

Zinc packs a punch by being an antioxidant, anti-inflammatory and immunity builder. To read more, please see GreenMedInfo.com's research on zinc and zinc deficiency.

© February 9th 2023 GreenMedInfo LLC. This work is reproduced and distributed with the permission of GreenMedInfo LLC. Want to learn more from GreenMedInfo? Sign up for the newsletter here //www.greenmedinfo.com/greenmed/newsletter.