Zinc is an essential element that plays catalytic, structural and regulatory roles in human biological systems. It is vital for growth and development, sexual maturation and reproduction, dark vision adaptation, olfactory (smell) and gustatory (taste) activity, insulin storage and release, and host immune defenses. It plays a crucial role in the protection and repair of DNA and regulation of hormone levels. Deficiency may cause growth retardation, pregnancy complications, frequent infections and poor wound healing. Good sources are oysters, wheat germ, pumpkin seeds and Brazil nuts. Recommended daily allowance is 15 milligrams/day. (For more detailed information, please visit ISM’s searchable database: Nutraceutical Search.)
Low zinc status may be a risk factor for pneumonia in the elderly…….In addition, recent evidence from the literature is presented demonstrating that low zinc status (commonly reported in the elderly) impairs immune function, decreases resistance to pathogens, and is associated with increased incidence and duration of pneumonia…….Inadequate stores of zinc might, therefore, be a risk factor for pneumonia in the elderly.
o Barnett, JB, Hamer, DH & Meydani, SN (2010). Low zinc status: a new risk factor for pneumonia in the elderly? Nutr Rev. 68(1), 30-7.
PURPOSE OF REVIEW: Zinc plays an essential role in numerous biochemical pathways. Zinc deficiency affects many organ systems, including the integumentary (skin, hair, nails), gastrointestinal, central nervous system, immune, skeletal, and reproductive systems…….RECENT FINDINGS: Zinc deficiency results in dysfunction of both humoral and cell-mediated immunity and increases the susceptibility to infection. Supplementation of zinc has been shown to reduce the incidence of infection as well as cellular damage from increased oxidative stress. Zinc deficiency is also associated with acute and chronic liver disease. Zinc supplementation protects against toxin-induced liver damage.
o Tuerk, MJ & Fazel, N (2009). Zinc deficiency. Curr Opin Gastroenterol. 25(2), 136-43.
The trace element zinc is a crucial cofactor for many proteins involved in cellular processes like differentiation, proliferation and apoptosis [cell death]………The immune system is strongly impaired during zinc deficiency, predominantly the cell-mediated response by T-lymphocytes……… Accordingly, disturbed zinc homeostasis [biological balance] increases the risk for infections, and zinc supplementation restores normal immune function. Furthermore, several disorders, like mycobacterial infections, asthma, diabetes, and rheumatoid arthritis are accompanied by decreased zinc levels and in some cases disease progression can be affected by zinc supplementation.
o Hönscheid, A, Rink, L & Haase, H (2009). T-lymphocytes: a target for stimulatory and inhibitory effects of zinc ions. Endocr Metab Immune Disord Drug Target, 9(2), 132-44.
PURPOSE OF REVIEW: Zinc is essential for multiple cellular functions including immunity. Many investigators have used zinc supplementation in an attempt to affect the outcome of various diseases. These efforts were aimed at either supporting immunity by zinc administration or correcting the zinc dependent immune functions in zinc deficient individuals………… SUMMARY: Zinc supplementation has been successfully used as a therapeutic and preventive agent for many conditions. Zinc functions as an intracellular signal molecule for immune cells.
o Prasad, AS (2009). Zinc: role in immunity, oxidative stress and chronic inflammation. Curr Opin Clin Nutr Metab Care. 12(6), 646-52.
Zinc deficiency in humans decreases the activity of serum thymulin [a hormone of the thymus gland, responsible for the production of T-cells – cells which provide immunity], which is required for maturation of T-helper cells………. In another study, zinc supplementation to humans decreased oxidative stress markers……….. We conclude that zinc has an important role in cell-mediated immune functions and also functions as anti-inflammatory and antioxidant agent.
o Prasad, AS (2007). Zinc: mechanisms of host defense. J Nutr. 137(5), 1345-9.
OBJECTIVE: The objective was to determine whether serum zinc concentrations in nursing home elderly are associated with the incidence and duration of pneumonia…….. CONCLUSION: Normal serum zinc concentrations in nursing home elderly are associated with a decreased incidence and duration of pneumonia.
o Meydani, SN et al (2007). Serum zinc and pneumonia in nursing home elderly. Am J Clin Nutr. 86(4):1167-73.
Zinc is essential for the immune system and elderly people have an increased probability for zinc deficiency, documented by a decline of serum or plasma zinc levels with age. Although most healthy elderly are not classified as clinically zinc deficient, even marginal zinc deprivation can affect immune function……….Studies with oral zinc supplementation show the potential to improve the immune response of elderly people by restoration of the zinc levels, showing that balancing the zinc status may be a way to healthy aging.
o Haase, H, Mocchegiani, E & Rink, L (2006). Correlation between zinc status and immune function in the elderly. Biogerontology, 7(5-6), 421-8.
There is substantial evidence to support an important role for zinc in immune processes. Adequate zinc status is essential for T-cell division, maturation and differentiation……….. Lymphocytes are one of the types of cells activated by zinc. Zinc is the structural component of a wide variety of proteins, neuropeptides, hormone receptors and polynucleotides………. Primary and secondary antibody responses are reduced in zinc deficiency, particularly for those antigens that require T-cell help,
o Baum, MK, Shor-Posner, G & Campa, A (2000). Zinc status in human immunodeficiency virus infection. J Nutr. 130(5S Suppl), 1421S-3S.
The results of more than three decades of work indicate that zinc deficiency rapidly diminishes antibody- and cell-mediated responses in both humans and animals. The moderate deficiencies in zinc noted in sickle cell anemia, renal disease, chronic gastrointestinal disorders……subjects with human immunodeficiency virus; children with diarrhea; and elderly persons can greatly alter host defense systems……….Conversely, short periods of zinc supplementation substantially improve immune defense in individuals with these diseases.
o Fraker, PJ, King, LE, Laakko, T & Vollmer, TL (2000). The Dynamic Link between the Integrity of the Immune System and Zinc Status. J. Nutr. 130(5), 1399S-1406S.
Proper intake of dietary nutrients is considered crucial for preventing the initiation of events leading to the development of carcinoma. Many dietary compounds have been considered to contribute in cancer prevention including zinc, which plays a pivotal role in host defense against the initiation and promotion of several malignancies……….zinc deficiency is an important factor in the development and progression of malignancy and zinc could be efficacious in the prevention and treatment of several cancers viz., colon, pancreas, oesophageal and head and neck.
o Dhawan, DK, & Chadha, VD (2010). Zinc: a promising agent in dietary chemoprevention of cancer. Indian J Med Res. 132(6), 676-82.
Zinc is known to have systemic effects such as regulation of the immune system……. zinc is reported to both induce apoptosis [cell death] in some cancers and to protect other cancer cells against apoptosis induced by other factors.
o Franklin, RB & Costello, LC (2009). The important role of the apoptotic effects of zinc in the development of cancers. J Cell Biochem. 106(5), 750-7.
Zinc not only improves cell mediated immune functions but also functions as an antioxidant and anti-inflammatory agent. Oxidative stress and chronic inflammation have been implicated in development of many cancers. In patients with head and neck cancer, we have shown that nearly 65% of these patients were zinc deficient based on their cellular zinc concentrations……….. In our patients, zinc status was a better indicator of tumor burden and stage of disease in comparison to the overall nutritional status.……. Thus, zinc supplementation should have beneficial effects on cancer by increasing apoptosis [cell death] in cancer cells.
o Prasad, AS, Beck, FW, Snell, DC & Kucuk, O (2009). Zinc in cancer prevention. Nutr Cancer, 61(6):879-87.
Poor zinc nutrition may be an important risk factor in oxidant release and the development of DNA damage and cancer…………..Thus, zinc deficiency not only caused oxidative stress and DNA damage, but also compromised the cells’ ability to repair this damage. Zinc adequacy appears to be necessary for maintaining DNA integrity and may be important in the prevention of DNA damage and cancer.
o Ho, E, Courtemanche, C &Ames, BN (2003). Zinc Deficiency Induces Oxidative DNA Damage and Increases P53 Expression in Human Lung Fibroblasts. J Nutr. 133(8), 2543-48.
There is strong evidence to support the fact that zinc, a key constituent or cofactor of over 300 mammalian proteins, may be of particular importance in host defense against the initiation and progression of cancer.
o Ho, E (2004). Zinc deficiency, DNA damage and cancer risk. J Nutr Biochem.15(10), 572-8.
Epidemiologic studies suggest that zinc deficiency may be associated with increased risk of cancer……. Zinc supplementation is associated with decreased oxidative stress and improved immune function, which may be among the possible mechanisms for its cancer preventive activity.
o Prasad, AS & Kucuk, O (2002). Zinc in cancer prevention. Cancer Metastasis Rev. 21(3-4), 291-5.
BACKGROUND: Zinc is involved in many essential cellular functions, including DNA repair and immune system maintenance.…….. OBJECTIVE: Our objective was to determine whether dietary zinc assessed near the time of prostate cancer diagnosis is associated with improved disease-specific survival…….. CONCLUSION: These results suggest that high dietary intake of zinc is associated with lower prostate cancer-specific mortality after diagnosis, particularly in men with localized disease.
o Epstein, MM et al (2011). Dietary zinc and prostate cancer survival in a Swedish cohort. Am J Clin Nutr. 93(3), 586-93.
The early detection of prostate cancer is a life-saving event in patients harboring potentially aggressive disease. With the development of malignancy, there is a dramatic reduction in the zinc content of prostate tissue associated with the inability of cancer cells to accumulate the ion.
o Ghosh, SK et al (2010). A novel imaging approach for early detection of prostate cancer based on endogenous zinc sensing. Cancer Res.70(15), 6119-27.
BACKGROUND: Prostate cancer is one of the most frequently diagnosed cancers in men……. CONCLUSION: This study suggests that zinc decreases the survival of androgen-independent prostate cancer cells…….. Thus, zinc may be qualified as a potential agent for the treatment of prostate cancer.
o Banudevi, S et al (2010). Effect of zinc on regulation of insulin-like growth factor signaling in human androgen-independent prostate cancer cells. Clin Chim Acta. 411(3-4), 172-8.
Zinc concentrations in the prostate are uniquely high but are dramatically decreased with prostate cancer. Studies have suggested that increasing zinc in the prostate may be a potential therapeutic strategy…….. The differential response to zinc in PC-3 [prostate cancer cells] and BPH-1 cells [hyperplasia cells] suggests that zinc may serve an important role in regulating cell growth and apoptosis [cell death] in prostate cancer and hyperplasia cells.
o Yan, M, Hardin, K & Ho, E (2010). Differential response to zinc-induced apoptosis in benign prostate hyperplasia and prostate cancer cells. J Nutr Biochem. 21(8), 687-94.
PURPOSE OF REVIEW: To summarize the recent findings related to the functions of zinc in prostate cancer prevention……….SUMMARY: Although epidemiological studies have shown mixed results, the experimental data strongly suggest a protective role of zinc in the prostate.
o Ho, E & Song, Y (2009). Zinc and prostate cancer. Curr Opin Clin Nutr Metab Care. 12(6):640-5.
BACKGROUND: Many studies have evaluated the association between vitamin and mineral supplement use and the risk of prostate cancer, with inconclusive results……… CONCLUSION: The finding that long-term zinc intake from multivitamins or single supplements was associated with a doubling in risk of prostate cancer adds to the growing evidence for an unfavorable effect of zinc on prostate cancer carcinogenesis.
o Zhang, Y, Coogan, P, Palmer, JR, Strom, BL & Rosenberg, L (2009). Vitamin and mineral use and risk of prostate cancer: the case-control surveillance study. Cancer Causes Control, 20(5), 691-8.
Zinc is an essential trace element for human health and is a critical component of many proteins……..The prostate is known to accumulate high levels of zinc, but levels are markedly decreased with cancer development……..Zinc deficiency may compromise DNA integrity in the prostate by impairing the function of zinc-containing proteins.
o Yan, M, Song, Y, Wong, CP, Hardin, K & Ho, E (2008). Zinc Deficiency Alters DNA Damage Response Genes in Normal Human Prostate Epithelial Cells. J Nutr. 138(4) 667-73.
OBJECTIVES: Zinc concentration is higher in the prostate than in most other tissues. Since information on the role of zinc on prostate carcinogenesis is controversial, we analysed the issue in a case-control study………. CONCLUSIONS: In this large study we found a direct association between high zinc intake and prostate cancer risk, particularly for advanced cancers.
o Gallus, S et al (2007). Dietary zinc and prostate cancer risk: a case-control study from Italy. Eur Urol. 52(4), 1052-6.
Prostate carcinogenesis involves transformation of zinc-accumulating normal epithelial cells to malignant cells, which do not accumulate zinc…Results suggest one possible mechanism for the inhibitory effect of zinc on the development and progression of prostate malignancy and might have important consequences for the prevention and treatment of prostate cancer.
Uzzo, RG et al (2002). Zinc Inhibits Nuclear Factor-B Activation and Sensitizes Prostate Cancer Cells to Cytotoxic Agents. Clinical Cancer Research, 8, 3579-83.
Prostate Zn2+ concentrations are among the highest in the body, and a marked decrease in the level of this ion is observed in prostate cancer. Extracellular Zn2+ is known to regulate cell survival and proliferation in numerous tissues… Therapeutic strategies based either on Zn2+ chelation or administration of Zn2+Citrate may be effective in attenuating prostate tumor growth.
Dubi, N et al (2008). Extracellular zinc and zinc-citrate, acting through a putative zinc-sensing receptor, regulate growth and survival of prostate cancer cells. Carcinogenesis, 29(9), 1692-1700.
Zn may be beneficial in the prevention and treatment of prostate cancer.
Clin Chem Lab Med. 2006; 44(2): 175-9.
Previous studies by our laboratory indicated that zinc ribbon domain-containing 1 (ZNRD1) suppressed the growth of gastric cancer cells with a G1 cell cycle arrest… In the present study, we have demonstrated that ZNRD1 could significantly inhibit the in vitro and in vivo growth of gastric cell line MKN28…Taken together, these results suggested that ZNRD1 might inhibit cell growth by targeting cell cycle-related genes and reducing tumor angiogenesis.
Hong, L et al (2007).Mechanisms of growth arrest by zinc ribbon domain-containing 1 in gastric cancer cells. Carcinogenesis, 28(8), 1622-8.