Zinc deficiency may alter how the immune system responds to inflammation

Raw Oysters for zinc

A new study has shown that a zinc deficiency contributes to chronic inflammation by causing improper immune cell activation and dysregulation of a protein that affects inflammation in the cell.

Read more about this research below.

Zinc is an essential mineral in human health required as a cofactor in numerous biological processes including DNA and protein synthesis, cell division, normal growth and development, neurological function and immunity, and wound healing. It is also required for normal taste perception and smell.

Zinc is naturally available in a wide variety of foods with higher amounts found in protein-rich foods including meat, poultry and seafood. Regular intake is necessary to maintain a steady state because it is not stored. Zinc deficiency most often occurs when intake is inadequate or poorly absorbed, when there are increased losses of zinc from the body, or when the requirement for zinc increases. Evidence from NHANES III data show that zinc intakes among older adults might be marginal, increasing the risk of a zinc deficiency.

Zinc deficiency is thought to contribute to the development of chronic diseases that involve inflammation and often show up in older adults who have a higher risk for zinc deficiency. In a new study published in the journal Molecular Nutrition & Food Research researchers examined how the immune system responds to zinc deficiency resulting in mechanisms that promote inflammation. Using in vitro cell culture and the aging mouse model, researchers found that zinc deficiency can induce an increase in the inflammatory response in cells by causing improper immune cell activation and dysregulation of cytokine IL-6, a protein that affects inflammation in the cell. When comparing zinc levels in both young and older living mice, the older mice with low zinc levels had a corresponding increase in chronic inflammation and decreased IL-6 methylation, an epigenetic mechanism that is used by cells to control gene expression.

The results of this study provide evidence of a potential link between zinc deficiency and increased risk of chronic inflammation, especially in aging adults.  

Here are the top 10 dietary sources of zinc:

  • Oysters
  • Beef & Lamb (Grass fed)
  • Wheat Germ
  • Spinach
  • Pumpkin and squash seeds
  • Cashews
  • Coco & Dark Chocolate (Not milk chocolate)
  • Pork & Chicken (Pasture raised)
  • Mushrooms.

If you don’t eat these foods two to three times a day, then time to look a high quality supplement which contains zinc.

Wong CP, Rinaldi NA, Ho E. Zinc deficiency enhanced inflammatory response by increasing immune cell activation and inducing IL6 promoter demethylation. Mol Nutr Food Res. 2015 Feb 5. doi: 10.1002/mnfr.201400761. [Epub ahead of print]

Dietary Zinc Intake Correlates with DNA Strength

Zinc is an essential mineral with a known role in maintenance of DNA integrity. However, until recently, no human studies have directly examined the role of zinc status on DNA damage in healthy adults.

A study published in the August 2009 American Journal of Clinical Nutrition examined the effects of varying levels of zinc intake on DNA damage in healthy adult males. Nine healthy men with reported mean daily zinc intakes of 11 mg/day were subjected to three different dietary periods.

* Days 1-13 = baseline period (11 mg zinc/day)
* Days 14-55 = zinc depletion (0.6 mg zinc/day for 1 week, then 4 mg zinc/day for 5 weeks)
* Days 56-83 = zinc repletion (11 mg zinc/day for 4 weeks with 20 mg supplemental zinc for the first 7 days)

Blood samples were collected on days 1, 13, 35, 55, and 83, and three key metrics were analyzed (DNA damage in peripheral blood cells, plasma oxidative stress, and antioxidant defense biomarkers).

As expected, dietary zinc depletion was strongly associated with increased DNA breakage in peripheral blood cells (day 13 compared with day 55, P < style="border-bottom: 1px dashed rgb(0, 102, 204); cursor: pointer;" class="yshortcuts" id="lw_1255669723_2">DNA strand breaks during the entire zinc depletion period (P = 0.006).

This study provides strong evidence for dietary zinc intake being a critical factor in maintaining DNA integrity in humans.

Song Y, Chung CS, Bruno RS, Traber MG, Brown KH, King JC, Ho E. 2009. Dietary zinc restriction and repletion affects DNA integrity in healthy men. AJCN 90(2):321-8.