Mineral absorption of diets containing natural carob fiber compared to cellulose, pectin and various combinations of these fibers Absorción de minerales de dietas que contienen fibra natural de algarrobas comparada con celulosa, pectina y varias combinaciones de estas fibras

Abstract

The influence of the consumption of natural carob fiber (NCF), an insoluble hypocholesterolemic fiber, as the unique dietary fiber or combined with cellulose (CEL) or pectin (PEC), on mineral bioavailability was studied. Six groups of rats were fed for 10 days diets containing 10% CEL, NCF, PEC or CEL+NCF, CEL+PEC and NCF+PEC mixtures at 50%. Food intake was lower with PEC than NCF and CEL+NCF, but final body weight was unaffected. Fecal weight showed significant differ ences in the following order: CEL, NCF, CEL+NCF > CEL+PEC, NCF+PEC > PEC. Percentage of calcium absorption was higher with CEL+PEC and NCF+PEC compared with the rest of fibers. Mag nesium absorption was also significantly enhanced in these two groups compared to NCF (p < 0.0004). Iron absorption did not show variations. Zinc apparent absorption was reduced by PEC, but the NCF+PEC mixture counterbalanced this effect. Liver iron was significantly lower with NCF+PEC than CEL, and liver iron concentration was significantly lower with NCF+PEC compared to CEL+PEC. Liver zinc was significantly higher with CEL+NCF than PEC while liver zinc concentrations were slightly higher with the former (p = 0.05 compared to NCF). The results indicate that NCF, compared to CEL and PEC, did not decrease the efficiency of calcium, magnesium and iron absorption in rats, while compared to PEC it increased zinc apparent absorption. Moreover, by combining NCF with PEC calcium and magnesium, absorptions enhanced in comparison with NCF alone, which was prob ably a result of the combination of soluble and insoluble fibers.