Any dietary or drug treatment with high-dosed micronutrients needs medical supervision.
The amount of zinc present in the retina decreases with age. Zinc is therefore thought to be an important factor in the onset of age-related macular degeneration (AMD). This is where the part of the retina responsible for central vision begins to deteriorate.
Zinc, vitamin C, vitamin E, beta-carotene, and copper were found to slow the development of AMD in a large-scale clinical trial. However, there have been studies that have observed no effect with zinc supplementation*.
Currently there is little evidence that zinc has a preventative effect on AMD but more research is needed.
Evidence is mixed, but many people believe that zinc lozenges or zinc nasal sprays can reduce the duration and severity of colds if used consistently from when they first notice symptoms*.
More high-quality research is required before conclusions can be drawn as to the effectiveness of zinc against certain strains of the common cold.
People who suffer from diabetes may often exhibit a moderate zinc deficiency.
More studies are needed, however, before zinc supplementation can be prescribed for diabetics *.
People diagnosed with HIV are more likely to exhibit a deficiency of zinc, which is vital for maintaining normal immune responses. A more advanced stage of the illness and also an increased mortality rate have been associated with low blood levels of zinc in HIV-positive people.
Authored by Dr Peter Engel in 2010, reviewed by Giorgio La Fata on 29.09.2017