Across 4 meta-analyses, 2 reported large beneficial effects (p < 0.001) of lower zinc levels in vitiligo and celiac disease patients, 1 found a large harmful effect (lower zinc in mild cognitive impairment), and 1 reported a neutral finding without statistical significance. The predominant effect direction was beneficial with a large effect size, though results varied by population. No consistent dose range or form were reported across studies.
Caveats: Evidence base is small (only 4 studies) — conclusions should be considered preliminary. One study showed a harmful association (lower zinc in mild cognitive impairment), indicating the effect may depend on the clinical population. Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests.
zinc (MD, -0.642; 95% CI, -0.731--0.554; p <0.001) levels were lower in the vitiligo group than in the control group.
Deficiencies in key micronutrients such as vitamin D, vitamin B12, albumin, calcium, zinc and iron were reported across revision types.
Zn (SMD: -0.77, 95%CI: -1.22-0.33) were significantly lower
Zn levels were significantly reduced (SMD -1.1398 (95% CI -2.0712 to -0.2084); P = 0.0242)