Deficiency of cobalt

Cobalt deficiency in humans is rare but can lead to megaloblastic anemia, similar to vitamin B12 deficiency, because cobalt is a central component of vitamin B12 (cobalamin). In ruminant animals, cobalt deficiency is more common and causes "wasting disease" or "bush sickness," characterized by poor growth, anemia, and reduced appetite, as their gut microbes require cobalt to synthesize vitamin B12.