Poorly absorbed from wheat

Normal levels of the element in pasture herbage are 0.5 3.5 mg/kg DM, while wheat grain contains 0.3. 6 mg/kg DM. Nickel is a relatively non-toxic element, is poorly absorbed from the digestive tract and does not normahy present a serious health hazard. 

Wheat bran and whole wheat cereals quantitatively contain high amounts of manganese and are often listed as particularly valuable sources of manganese. However, zinc also is contained in appreciable amounts in wheat bran and whole wheat products but is poorly absorbed by the human from these sources. This has been attributed to either the phytate or the fiber contents of these products or a combination of these two dietary factors. These same factors may also affect the absorption of manganese. 

A major complication of constipation in the elderly is fecal impaction, a potentially serious condition that can result from ignoring impulses to defecate. Impaction is the buildup of fecal mass that becomes too large to expel. Increasing dietary fiber is part of the management program for chronic constipation of the elderly. Addition of bran (6-20 g/day) increases fecal weight and increases the frequency of defecation. When wheat bran is not effective, the laxative lactulose is recommended. Lactulose is a disaccharide composed of galactose and fructose connected by a p(l 4) bond. This compound is absorbed poorly in the small intestine because of the absence of enzymes that catalyze its hydrolysis. 

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