Investigations assessing the effects of dietary fibre
on month to anus transit time in human have often yielded conflicting and,
hence, inconclusive results. Only a few of the investigations reported
successfully measured digesta passage for those on controlled diets (Cummings,
J.H et al, 1978, Stasse Woitheus, M.
1980). Wheat bran has been the main fibre source tested, though oat flakes (Walker,
A.R.P. 1975) bagasse, purified cellulose, guar pectin, fruits and or vegetables
Cummings, J.H et al, 1978 Walker,
A.R.P. 1975, cowgill, G.R. and sullivan A.J. 1933, park T.G 1973).
Were tested
in some studies. Bagasse was effective in reducing transit time, whereas the
effect of orange fibre was only slight (Walker, A.R.P. 1975). and added
cellulose or pectin had no effect, which suggests that different fibre sources
exert different effects on intestinal function. Occasionally, marker transit
data from subjects with gastrointestinal disterlxances were compared to those
obtained from health, normal controls. Types of disorders have varied within
experiments and have included spastic colon, proctitis, constipation,
diverticular disease, diarrhea and irritable bowel syndrome (Harvey, R.F, et al 1973, Paylor, D.K., et al 1975).
The differential passage of
chromic oxide and poly ethylene glycol (PEG) demonstrated in subjects with
diverticular disease and cholerrhoeic enteropathy (Findlay, ].M. et al 1974). Suggests that a certain
diseases state can affect marker passage more profoundly than any dietary
variable. Nearly all studies that allowed self-selected diets did not mention a
control or total level of food intake, which has consistently been variable affecting
rate of digest a passage in animals (castle, E.J 1956 and Grovum, W.L and
WillIams, V.J. 1977). Experiments in humans generally have not been designed to
asses the extent that inter subject variability, disease condition and the
amount or rates in addition to the presence of bran or other fibre source.
Studies of dietary fibres and their effects on bowel
functional have indicated various changes in stool output and composition, not
all of which are solely attributable to water binding properties measurable in
vitro (Stephen, A.M $ comings, J.H. 1979). Research reports examining the
effects of added dietary fibres on stool bulk and composition have been
reviewed (Kelsay, IL 1978), and it is generally agreed that fibre addition to
an otherwise low fibre diet increases stool volume and improves taxation.
Dietary fibre is not a uniform material and varies widely in chemical
composition and physical properties with taxonomic class large differences
between intact vegetable and cereal fibres and isolated cellulose preparations
have been reported for measure volume (Van soest. PJ. and Robertson. JB .1976).
Variability in physiochemical properties permits speculation that the source,
level of intake and the bulk density of dietary fibre consumed would alter and
dry matter (DM), the frequency of defecation and the moisture content of the
stool. These hypotheses were tested in a human metabolic trial by using health
subjects with no history of gastrointestinal disease, An analysis of present
methods for mouth-to-anus transit time measurement and compartmental turnover
kinetics is presented else where (Wrick, K.L.F 1979).
CONSTRAINTS TO GREATER USE OF LEGUME
The use of legume in the human diet can also be
problematic. legume seeds generally contain 20% to 30% protein and are ys rich,
complementing the nutritional profiles of cereals and tubers in the diet
(Duranti $ Cius, 1997). However, legumes are limited in sulfur amino acids,
contain ant nutritional factors including lectins and flatulence factors, and
are commonly hard to cook. Preference for particular grain types or seed
affects martability.
Forage legume have been the foundation for diary and
meat production for centuries (Russelle, 2001). When properly managed, they are
rich sources of protein, fibre and energy.