Dietary fibre consumption in Britain: new estimates and their relation to large bowel cancer mortality.
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Adult↗
Biomedical subjects
S A Bingham
Publications and source records attributed to S A Bingham.
Urine nitrogen as an independent validatory measure of dietary intake: a study of nitrogen balance in individuals consuming their normal diet.
In order to determine the value of 24 h urine nitrogen (N) excretion as a way of validating dietary methods of measuring protein intake in individuals, daily N intake and excretion has been measured in eight healthy subjects while consuming their usual, varying, diets for 28 days. Daily duplicates of all food eaten were obtained and consecutive 24 h collections of urine and feces were made throughout and analyzed for N by the Kjeldahl method. The completeness of the 24 h urine collections was verified by the use of PABA and of feces by radiopaque pellets. N losses in blood and from the skin were measured. The within person variation in dietary intake ranged from 14 to 26% (coefficient of variation, CV) while urine N was more constant, varying from 11 to 18% (CV) within individuals. In these subjects eight 24 h urine collections, verified for their completeness, were sufficient to estimate dietary N intake to within 81 +/- 5% (SD) as assessed by 18 day dietary records.
Adult↗
Epidemiology of dietary fibre and colorectal cancer: current status of the hypothesis.
The hypothesis that lack of dietary fibre in the diet is responsible for a variety of large bowel problems, including cancer, has stimulated much discussion and research over the past 15 years. However, the epidemiological examination of this hypothesis has been hampered by the absence of data on the fibre content of most of the world's foods. In Scandinavia and Britain where the consumption of the major chemical fraction of dietary fibre, the non-starch polysaccharides, has been measured using accurate methods, significant negative associations have been shown with colon cancer occurrence. These studies suggest that non-starch polysaccharides may be protective in populations at otherwise high risk of colon cancer from an excess of meat and fat. However, methodological problems in the assessment of non-starch polysaccharide consumption in individuals preclude the use of case control studies in verifying these associations within a single homogeneous population.
Colonic Neoplasms↗
Non-starch polysaccharides as a protective factor in human large bowel cancer.
The hypothesis that lack of dietary fibre in the diet is responsible for a variety of large bowel problems, including cancer, has stimulated much discussion and research over the past 15 years. However, the epidemiological examination of this hypothesis has been hampered by the absence of data on the fibre content of most of the world's foods. In Scandinavia and Britain where the consumption of the major chemical fraction of dietary fibre, the non-starch polysaccharides has been measured using accurate methods, significant negative associations have been shown with large bowel cancer occurrence. These studies suggest that non-starch polysaccharides may be protective in populations at otherwise high risk of large bowel cancer from an excess of meat and fat. However, methodological problems in the assessment of non-starch polysaccharide consumption in individuals preclude the use of case control studies in verifying these associations within a single homogeneous population.
Colonic Neoplasms↗
The use of creatinine output as a check on the completeness of 24-hour urine collections.
The use of creatinine as a check on the completeness of 24-h urine collections is based on the assumption that excretion per kg body mass is constant. In a study of eight volunteers maintained on uniform diets the within-subject coefficient of variation (CV) in daily 24-h creatinine excretion was only 4 per cent under conditions in which the completeness of collections was assured. Cooked meat contains creatine and creatinine and an addition of 260 g/d cooked meat to the diet of four volunteers on a metabolic diet increased urine creatinine excretion by 23 per cent. A further source of variation in urine creatinine is the completeness of the collection itself. A new marker, PABA, was used to check the completeness of 24-h urine collections in eight subjects studied for 28 d whilst eating their normal diets. The within-subject CV of 9 per cent for 24-h creatinine excretion was not significantly different from that of 13 per cent for overall urinary N. In 122 complete 24-h urine specimens collected from a randomly selected population, the CV in creatinine excretion was 18 per cent. Twenty-one urine samples were incomplete, of which only 3 would have been detected on the basis of low creatinine by conventional standards. Of 39 hospital patients asked to collect 24-h urine samples, 12 provided incomplete samples, of which only 4 had low creatinine excretion. It is concluded that PABA is a more sensitive and reliable verification of the completeness of 24-h urine collections than creatinine.
4-Aminobenzoic Acid↗
Dependence of 24 h energy expenditure in man on the composition of the nutrient intake.
The influence of the nutrient composition of food on energy expenditure during a 24 h period was investigated in adult volunteers. The maximum probable effect was determined using iso-energetic diets high in either protein or in glucose. Two men and four women took part in the study. Their body-weights and body composition were within the normal range. Each subject lived for 28 h in a whole-body calorimeter set at 26 degrees, on two separate occasions. During each session they ate one of the following iso-energetic diets: high-protein-low-carbohydrate or high-glucose-low-protein. Energy expenditure was determined while the subject followed a pre-set pattern of activity. A 24 h collection of urine was made and total nitrogen, creatinine and urea excretions were determined, so that heat production could be corrected for protein metabolism. Two independent measures of energy expenditure were made: direct calorimetry was used to obtain heat loss partitioned into its sensible and evaporative components, while indirect calorimetry was used to estimate heat production from oxygen consumption, carbon dioxide production and N excretion. There was good agreement between the two estimates of 24 h energy expenditure: for the twelve sessions in the calorimeter the mean difference between heat production and heat loss was only 0.4 (SEM 0.39)%. The results showed that nutrient composition can have a marked influence on 24 h energy expenditure in adult humans. Mean values of 8659 (SEM 230) kJ and 7735 (SEM 250) kJ were obtained for the high-protein and high-glucose diets respectively. This 12% increase in energy expenditure on the high-protein intake was significant (P less than 0.001). On the high-glucose intake, total heat loss comprised 22 and 78% evaporative and sensible heat losses respectively. The increase in heat loss on the high-protein intake was accounted for by a 39% increase in evaporative heat loss and a 7% increase in sensible heat loss. It is concluded that the composition of the nutrient intake has a greater influence on the metabolic rate of adult humans than has been suggested by some groups of workers in recent years.
Adult↗
The effects of breads containing similar amounts of phytate but different amounts of wheat bran on calcium, zinc and iron balance in man.
The capacity of wheat bran to impair mineral absorption independent of its phytate content was studied by metabolic balance studies in man. Three breads were prepared, equivalent to white, brown and wholemeal, by adding bran in different quantities to white flour. Calcium, iron, zinc and sodium phytate were added to the loaves to make the amounts equal in all breads. Six healthy volunteers were studied for three consecutive 24-d-periods during which they ate a controlled diet, typical of that normally consumed in the UK but with 200 g bread/d. Only the type of bread changed between each dietary period. The phytate contents (mmol) of 200 g of each of the breads after baking were: white 2.3, brown 2.1 and wholemeal 2.2; non-starch polysaccharide contents (g) were: white 3.3, brown 10.9 and wholemeal 18.7. The increased amount of bran in the breads increased stool output in the expected way but no change was seen in Ca, Zn and Fe balance. Blood levels of these minerals remained unchanged. It is concluded that wheat bran and, in particular, the cell-wall polysaccharides of bran, are unlikely to exert a significant effect on mineral absorption in man, in amounts customarily eaten, independently of the effect of phytate present in the bran.
Adult↗
Nonstarch polysaccharide consumption in four Scandinavian populations.
Nonstarch polysaccharide (NSP) intake was measured in representative samples of 30 men aged 50-59 in 2 urban and 2 rural Scandinavian populations that exhibited a 3-4 fold difference in incidence of large bowel cancer. Intake was measured by chemical analysis of complete duplicate portions of all food eaten over one day by each individual. NSP intakes showed a rural-urban gradient, with 18.4 +/- 7.8 g/day in rural Finland and 18.0 +/- 6.4 g/day in rural Denmark versus 14.5 +/- 5.4 g/day in urban Finland and 13.2 +/- 4.8 g/day in urban Denmark. NSP intakes were also calculated (using food tables) from weighed food records kept over 4 days, one of which was the day on which the duplicate collection was made. Intakes were 2-2.5 g/day higher with this method than with direct chemical analysis, mainly because published tables of values have become outdated and inaccurate as a result of improved methods for measuring NSP in food. Individual variation from day to day in NSP intake was considerable. Average NSP intake and intake of some of its component sugars were inversely related to colon cancer incidence in this geographical comparison. To show a relationship at the individual level between diet and cancer risk in a prospective study would require detailed and accurate methods for the assessment of NSP consumption.
Colonic Neoplasms↗
Epidemiological assessment of dietary intake.
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Aged↗