Zinc supplementation has no effect on circulating levels of peripheral blood leucocytes and lymphocyte subsets in healthy adult men

Abstract

As a result of evidence documenting harmful effects of Zn supplementation on immune function and Cu status, thirty-eight men were recruited onto a Zn supplementation trial. The aim was to examine the effects of chronic Zn supplementation on circulating levels of peripheral blood leucocytes and lymphocyte subsets. Subjects (n 19) took 30 mg Zn/d for 14 weeks followed by 3 mg Cu/d for 8 weeks to counteract adverse effects, if any, of Zn supplementation on immune status resulting from lowered Cu status. A control group (n 19) took placebo supplements for the duration of the trial. Dietary intakes of Zn approximated 10 mg/d. Blood samples, taken throughout the trial, were assessed for full blood profiles and flow cytometric analyses of lymphocyte subsets. Putative indices of Cu status were also examined. Results indicate that there was no effect of Zn supplementation on circulating levels of peripheral blood leucocytes or on lymphocyte subsets. Cu status was also unaltered. Independent of supplement, there appeared to be seasonal variations in selected lymphocyte subsets in both placebo and supplemented groups. Alterations in circulating levels of B cells (cluster of differentiation (CD) 19), memory T cells (CD45RO) and expression of the intracellular adhesion molecule-1 (CD54) on T cells were observed. Findings indicated no adverse effects of Zn supplementation on immune status or Cu status and support the US upper level of Zn tolerance of 40 mg/d. The seasonal variations observed in lymphocyte subsets in the group as a whole could have implications for seasonal variability in the incidence of infectious diseases.

Zinc in pharmacological doses suppresses allogeneic reaction without affecting the antigenic response

“…Full blood profiles were not assessed since it is known that zinc supplementation has no effect on circulating levels of peripheral blood leucocytes and lymphocyte subsets in healthy donors. 24 These ex vivo experiments confirmed the in vitro results. IFN-g release of PBMC was compared prior to and after zinc intake.…”

Zinc and the Diabetic Heart

“…In general, Zn is not very toxic, but excessive and chronic Zn supplementation still causes several symptoms including Cu deficiency (Cai et al 2005), which is also a risk factor for cardiomyopathy (Davison et al 1992;Nath 1997). Therefore, Zn supplementation together with other components such as chromium, magnesium, low-dose Cu and antioxidants has been proposed (DiSilvestro 2000; Anetor et al 2002;Baydas et al 2002;Bonham et al 2003;Alissa et al 2004). In addition, Zn salts have several disadvantages such as low absorption and short turnover.…”

Dietary zinc requirement of Siberian sturgeon (Acipenser baerii, Brandt 1869) juveniles, based on the growth performance and blood parameters

“…Yadrick et al (1989) expressed that supplemental dietary zinc decrease hematocrit, without changing the hemoglobin. In contrast, Bonham et al (2003) stated that daily 40 mg Zn supplementation to the diet does not influence the blood parameters. In another investigation with 2-month-old rats, supplementation of 12 mg Zn kg -1 diet decreased the hemoglobin 85% compared to the control animals (Zaporowska and Wasilewski 1992).…”