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Zinc is a trace mineral, so we need only small amounts—but it plays a big role in our health. It’s estimated that zinc binds with more than 3,000 different proteins in the human body, and influences many of our internal processes.
1. A Healthy Immune System
“Zinc is a critical factor for the functioning of many cellular processes, and loss of zinc in the cell leads to various problems, especially in your immune cells,” says Emily Ho, PhD, a leading zinc researcher at the Linus Pauling Institute at Oregon State University in Corvallis.
In early attempts to find a treatment for COVID-19, the addition of high-dose zinc supplements to a drug cocktail has shown some success. But this doesn’t mean that zinc alone is a treatment for the virus. Rather, adequate zinc helps your immune system ward off or fight all types of infections. “It’s important to make sure you get enough zinc,” says Ho.
Related: 31-Day Immune Health Challenge
She favors getting the mineral from protein-rich foods. “If you do take zinc supplements,” she says, “we don’t recommend high doses—take near the RDA level, 10–15mg.” The recommended upper limit for zinc is 40mg per day. “At higher doses,” adds Ho, “It will cause problems with copper and iron.”
2. Shorter Colds
Zinc lozenges are proven to shorten the duration of colds by up to 40 percent when taken within 24 hours of the first symptoms. Lozenges should dissolve in your mouth and need to be taken every 2–3 hours. The total daily dose of zinc will exceed the usual 40-mg daily limit, but is not harmful if taken for no more than a week or two.
3. Faster Wound Healing
Topical ointments with zinc oxide help cuts, burns, abrasions, and skin ulcers to heal, and also reduce risk of infection in wounds. Zinc helps reduce inflammation and helps with production of collagen, as well as enhancing the immune system.
4. Less Diabetes
Zinc enhances insulin function and regulation of blood sugar in diabetics and in healthy people. Some, but not
all, studies have found that higher levels of zinc were linked to decreased risk of diabetes—up to 50 percent decreased risk for women. And two placebo-controlled trials in Asia found that 20–30 mg of zinc daily, taken for 6 months to a year, lowered blood sugar in people with prediabetes.
5. Longer-Lasting Vision
The Age-Related Eye Disease Studies (AREDS) investigated supplements for age-related macular degeneration, a leading cause of blindness in older people. These studies found that a combination of antioxidants with either 25 mg or 80 mg of zinc slowed the progression of the disease and helped to prevent it when taken on an ongoing basis. Products with the studied combinations are usually described as “AREDS” formulas.
Related: 16 Signs You Need More Zinc
6. Better brain function
In infants, zinc deficiency delays neurological development. In adults with Alzheimer’s, zinc levels are typically low, and preliminary research shows that zinc supplements may slow down mental decline.
Other studies have found that zinc levels are low in people suffering from depression and that zinc supplements may reduce symptoms. In addition, Australian studies of middle-aged and older people found that they were less likely to develop depression if their diets contained higher amounts of zinc.
7. Healthier Testosterone
Studies show that zinc is essential for men’s sexual health, sperm production, and fertility. In young men, a study found that low levels of zinc—induced by a temporarily zinc-restricted diet—lowered levels of testosterone. In older men with low testosterone, zinc supplements increased levels.
The Future of Zinc
The COVID-19 pandemic shone a brighter light on zinc, and research is heating up. In the past year, about 35 clinical trials with zinc were published in major scientific journals. At the time of this writing, more than 270 clinical trials with zinc are underway.
In supplements, zinc comes in a variety of forms in individual zinc products, as well as in multis or other formulas. Studies have shown that zinc picolinate and Optizinc (zinc methionine) are better absorbed than zinc citrate and zinc gluconate, and the latter two are better absorbed than zinc oxide (which is found mostly in sunscreens and ointments). Other forms include zinc acetate, sulfate, and orotate, and food-based brands of zinc such as MegaFood, Garden of Life, and New Chapter.
Caution: Avoid zinc nasal gels and nasal sprays because they can permanently damage the sense of smell.