Zinc is an essential mineral found in many foods with animal products being the highest and most bioavailable sources. Zinc plays a major role in a variety of functions within the body such as wound healing, immune function, growth and development, moderating thyroid and insulin functions, along with possessing antioxidant properties. Zinc is also an essential nutrient in the gut barrier function, ensuring that the intestinal wall is strong and non-porous. The recommended daily allowance (RDA) is between 8-11mg depending on gender and age.
It is unlikely that one has an overt deficiency in zinc, however individuals with conditions such as pregnancy, gastrointestinal disorders that affect intestinal absorption and intestinal wall integrity such as Colitis, Crohn’s disease, dysbiosis, and leaky gut, or colds, or those taking medications that can deplete zinc, such as thiazide diuretics and ACE inhibitors, may have higher zinc requirements. Zinc supplementation has been proven effective in a wide array of medical conditions ranging from anemia and ADHD to depression and the common cold. Recent studies show that zinc deficiency induces damage to the gut membrane barrier, while zinc supplementation may enhance the gut barrier function and aid in restoring the gut lining.
Dosing for zinc is based on the condition and salt form of the supplement.
Zinc is present in numerous foods with oysters and beef as the highest and most bioavailable sources, and vegetarian sources, including nuts, beans, and whole grains. It may also be obtained through a variety of commercially available products including pills, lozenges, nasal sprays, topical products and homeopathic preparations. Zinc exists as a salt form and is available in an array of salts including citrate, gluconate, picolinate, sulfate and oxide amongst others.
Although proven safe in doses of up to 40mg/day, zinc supplementation can cause minor side effects. It is important to note that if one type of zinc salt seems to cause a side effect, switching to another from may alleviate those symptoms.
- Digestive distress: Zinc can cause diarrhea so it is recommended to take with food. If that does not alleviate the side effect, another salt form of zinc may be better tolerated.
- Drug interactions: Zinc supplementation can inhibit copper absorption so it is recommended that copper be taken alongside it either through a multi vitamin or via supplement. As well, zinc should not be taken within 2 hours of some antibiotics such as tetracycline or quinolones due to the binding nature of the antibiotic and minerals. Finally, some medications such as thiazide diuretics, can cause zinc (and other mineral) depletion.
The GutBiome Approach
Eating a diet rich in zinc-containing foods, such as nuts and legumes is recommended. For those individuals who have a higher zinc recommendation (populations described above), specifically those individuals who suffer from increased intestinal permeability (or leaky gut), bacterial overgrowth (or dysbiosis), and other digestive conditions such as Crohn’s and Colitis, taking a daily zinc supplement is recommended. Further scientific research is needed to fully understand the role of zinc supplementation in improving the integrity of the gut lining, but to date, studies suggest that zinc supplementation is beneficial in enhancing gut barrier function.
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