Human metabolism, effects pectin

BEHALL AND REISER Effects of Pectin on Human Metabolism... 

Behall, K Reiser, S. Effects of pectin on human metabolism. Chemistry and funetions of pectins. Washington, DC American Chemical Society, p. 248-265, 1986. 

Although little is known about the effects of pectins on the absorption of manganese, administration of pectin has been shown to increase the excretion of bile acids in humans (48). In the only previous study related to the influence of pectin on manganese metabolism, fuccidan—a polyuronic acid of seaweed origin—was found to reduce the uptake of manganese in tied-off segments of rat jejunum by up to 77% (51). 

Two major approaches have been used to study the effects of fiber on humans 1) to replace low-fiber foods with higher fiber foods and 2) to add refined fibers to self-selected or controlled diets. High pectin foods or refined pectin have been fed to man and animals alone or in combination with other fiber sources to investigate the effect of pectin on metabolic parameters. 

It is proposed that polyphenols and fiber are the main contributors to the observed effects, either individually or in a synergistic interaction. However, bioavailability and metabolism of the numerous apple polyphenols is not completely understood. Moreover, limited data are available for the characterization of apple fiber, in particular pectin, in the different apple varieties and the impact of the physicochemical properties and structure on the degree of effect. Suitably powered randomly controlled, human dietary intervention studies with long intervention periods are required to clarify the protective effects of apples and juice consumption. Further in vivo animal models are also necessary to explore the potential multiple mechanisms of actions. 

---