Zinc is a critical nutrient that many people are deficient in. Zinc is needed for hundreds of enzyme reactions in the body and is extremely important for our health. It is very easy in this day and age to become zinc deficient because of a few factors. We tend to “waste” zinc while we are stressed, so we burn through it quicker. Vegetarian and vegan diets are very low in zinc, but the SAD diet is also very low in zinc. We need sufficient stomach acid to even digest and utilize zinc, so even if people are getting enough of it they might not be absorbing it well. Although even with sufficient stomach acid, we do not absorb zinc very well! Heavy metal toxicity (especially mercury and cadmium) can interfere with zinc absorption.
WHY DO WE NEED ZINC?
Zinc is needed for at least 300 different enzyme reactions in the body. Some of the most important things we need zinc for include:
- Digestive enzymes
- Proper growth
- Eye Health
- Immune system health: T-cells, macrophages, eosinophils
- Insulin production
- Adrenal hormone production: Cortisol, Aldosterone, Progesterone, Testosterone
- Wound healing
- Maintaining healthy skin
- Detoxification binding proteins: Metallothionein, Glutathione, Ceruloplasmin
Zinc Deficiency Symptoms:
- slowing of growth and development
- skin rashes
- chronic and severe diarrhea
- immune system deficiencies
- impaired wound healing
- diminished appetite
- impaired taste sensation
- night blindness (because Zinc and retinol have a direct relationship)
- swelling and clouding of the corneas
- behavioral disturbances
How to Test and Treat Zinc Deficiency:
The best ways to asses zinc status are a hair tissue mineral analysis, and blood tests (both plasma and RBC zinc are helpful).
Supplemental zinc can cause issues for many people. Too much isolated zinc can actually create a copper deficiency over just the span of a few weeks. Too much zinc inhibits the production of a copper-binding protein called metallothionein. Metallothionein traps copper and prevents it from being absorbed. Also, the longer you supplement with zinc, the less zinc you actually absorb. The recommended amount of zinc will vary person to person as well, so there is no general recommendation on the amount of zinc you may need. Males generally need more zinc than females because of zinc’s relationship with testosterone.
Getting zinc from food is the best. From Linus Pauling: “Zinc bioavailability (the fraction of zinc retained and used by the body) is relatively high in meat, eggs, and seafood because of the relative absence of compounds that inhibit zinc absorption and the presence of sulfur-containing amino acids (cysteine and methionine) that improve zinc absorption. The zinc in whole-grain products and plant proteins is less bioavailable due to their relatively high content of phytic acid, a compound that inhibits zinc absorption.”
Oysters and beef are two of the highest foods in zinc. Make sure that your meat is grass-fed and free of added hormones and steroids and that your oysters come from a reputable, clean source. Some other foods high in zinc are turkey, pumpkin seeds, crab and beans.
We want to make sure that we have sufficient stomach acid to properly utilize our nutrients. Check out my post on stomach acid here!
Zinc’s antagonists include supplemental calcium and iron- both things I do not recommend anyway!
Zinc helps make folate more bioavailable. Zinc is needed to convert retinol (Vitamin A) to retinal. A deficiency in zinc an lead to low levels of bioavailable vitamin A as well.
Want to read more about zinc? Check out this article from the Linus Pauling Institute.