Serum cholesterol levels pectin effect

Recently the means by which pectin lowers cholesterol levels and even the validity of this effect have been questioned. Upon finding no bile salt binding capacity for soluble pectin, Baig and Cerda (76) proposed that pectin lowered serum cholesterol levels by forming insoluble complexes with the serum low density lipoproteins (LDL) which transport circulating cholesterol. Complexing of LDL by citrus pectin was observed in vitro, but the way in which pectin or some component thereof enters the blood stream to effect such binding in vivo has not been determined. 

Palmer, G.H. and Dixon, D.G. 1966. Effect of pectin dose on serum cholesterol levels, Am. J. Clin. Nutr., 18 437 142. 

The effectiveness of pectin in lowering cholesterol in tissues can be influenced by many factors (1) The type of pectin - that with methoxy groups and with high viscosity (35, 36) was reported to be more effective. The results from a comparative study of several types of pectin by Mokady (36) are shown in Table IV. Neither a high degree of methylation nor high-viscosity alone was very effective (2) the level of dietary fat - with a high-fat diet (2% corn oil plus 18% beef tallow), pectin has no effect on serum cholesterol level (57). Tsai et al. also reported that with... 

Pectin with 62% D.E. largely counteracted the increase in liver cholesterol levels brought about by dietary cholesterol. Low ester pectin (30% D.E.), polygalacturonic acid (PGA), and 50% esterified PGA were all without effect. Conflicting reports on the efficacy of pectin as a hypocholesterolemic agent may be due to variations in these parameters. For example, citrus pectin was found to be more effective than tomato pectin in lowering serum and hepatic cholesterol levels of rats (79). 

D.E. values for the citrus and tomato pectins were 56 and 40%, respectively. Thus, differences in D.E. levels rather than pectin source could have accounted for the superior effectiveness of citrus pectin. Mokady (80) and Judd et al. (81) confirmed that serum cholesterol reduction is most pronounced with high D.E., high-molecular-weight pectin (Table I). 

The Effect of Pectin and Fat on Serum and Liver Cholesterol Levels and the Recovery of Radioactive Cholesterol (% Intake) in the Liver of Rats 48-Hour and 72-Hour After Feeding Cholesterol-4-14c... 

The health effects of pectin are receiving more interest. It is generally accepted that a high fiber diet is beneficial to one s health. There is clear evidence that pectin can lower cholesterol levels, serum glucose levels and may also have anti-cancer activities (Yamada, 1996 BehaU Reiser, 1986). 

Dietary fiber may influence lipidemia and atherosclerosis. Substances designated as insoluble fibers (wheat bran, for instance) possess laxative properties but have little effect on serum lipid levels. Soluble fibers (gel-forming fibers such as pectin or guar gum) influence lipidemia and glycemia. Oat bran, which contains /3-glucans, which are soluble fibers, will lower cholesterol levels despite its designation. 

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