Effect of dietary fibres on bioavailability of vitamin A and thiamine

Different sources of dietary fibre (cellulose, pectin, Isabgol, cabbage and guava) were fed to weaning rats for 5 weeks to study their effect on serum vitamins. Both the plant foods (cabbage and guava) were analysed for dietary fibre. Guava was found to be a good source of dietary fibre constituting 51.77% of dry pulp, whereas cabbage contained only 16.17%. Cellulose was the major component of dietary fibre in both the plant foods. The concentration of vitamin A and thiamine in the serum of fibre-fed rats was significantly lower than that of rats on a fibre-free diet. However, the amount of vitamin A in serum decreased significantly with the increase in level of dietary fibre, but the decrease was non-significant in the case of thiamine.