The effect of dietary vitamin E deficiency on plasma zinc and copper concentrations

Vitamin E and zinc have a number of functions in common, including membrane stabilisation, antioxidant function and modulation of prostaglandin metabolism. Previous studies have shown vitamin E malabsorption during zinc depletion and it appears that there is an interaction between the two nutrients. In this study we have investigated whether vitamin E deficiency affects zinc and copper concentrations in experimental animals. Male Wistar rats were maintained on a vitamin E deficient diet for either 6 or 10 months. At the end of the experimental period all animals had undetectable plasma vitamin E levels and increased red cell fragility. Plasma zinc concentrations were significantly reduced in all vitamin E deficient animals compared to control rats (p<0.002) and copper levels were reciprocally elevated (p<0.002). It appears likely that decreased zinc levels may represent redistribution of circulating zinc to tissues and cells as a secondary antioxidant, or for membrane stabilisation or prostaglandin synthesis.