“…As has been shown for lead, calcium supplementation reduces manganese uptake, enhances its fecal excretion, and decreases its concentration in the blood and liver (Johnson and Kies, 1989). Mn absorption is inhibited by a high load of dietary calcium in several animal species (Hawkins et al, 1955;Van Barneveld and Van den Hamer, 1985;Smith and Kabaija, 1986) as in man (Greger et al, 1977;Freeland-Graves and Lin, 1991), but this effect has occasionally not been observed (Spencer et al, 1979). Manganese uptake by brush border intestinal vesicles is also markedly inhibited by iron, cobalt and zinc (Kabata et al, 1989).…”