EFFECT OF SOLUBLE OR PARTLY SOLUBLE DIETARY-FIBERS SUPPLEMENTATION ONABSORPTION AND BALANCE OF CALCIUM, MAGNESIUM, IRON AND ZINC IN HEALTHY-YOUNG MEN

Objectives: This study is aimed at investigating the effect of feeding a soluble or partly soluble fibre rich-diet on the apparent absorptio n and balance of calcium, magnesium, iron and zinc in healthy young me n, by using a chemical balance technique. Study design: Nine healthy y oung men were given a control diet or the same diet complemented with either inulin (soluble) or sugar beet fibre (partly soluble) during 28 d periods according to a 3 x 3 latin square design with three repetit ions. During the 20 d adaptation period to fibre ingestion, experiment al fibres were incorporated into bread (60%) and liquid foods (40%) up to a maximum of 40 g/d. Ca, Mg, Fe and Zn were measured in diets and in a 8 d urine and faecal composites to assess mineral absorption and balance. Results: The dietary mineral intake provided (mg/d) 859 +/- 1 96 of Ca; 311 +/- 43 of Mg; 11.6 +/- 1.7 of Fe; and 11.1 +/- 1.6 of Zn from the control diet. The apparent absorption of minerals from the c ontrol diet was (%) Ca: 21.3 +/- 12.5; Mg: 46.3 +/- 10.9; Fe: 21.8 +/- 12.3 and Zn: 14.0 +/- 14.5 (mean +/- s.d.). Ingestion of inulin signi ficantly increased the apparent absorption and the balance of Ca. Suga r beet fibre ingestion resulted in a significant increase in Ca intake and balance, without modification its apparent absorption. Apparent a bsorption and balance of Mg, Fe and Zn were not significantly altered by the ingestion of either experimental fibre. Conclusions: Addition o f the two experimental fibres (inulin or sugar beet fibre) to normal m ixed diets can improve Ca balance without adverse effects on other min eral retention.