174
may have occurred after the high-fibre meal. Another, perhaps less obvious, factor which may be very important in explaining the results is the ability of fibre to limit diffusion towards the absorptive mucosal surface. 14 Both guar and pectin form gels or viscous solutions when hydrated. In vitro 1% guar gum in solution has been shown to inhibit by 40% the uptake of histidine by the everted intestinal sac of the rat." A twofold delay in mouth-to-caecum transit-time has also been shown to occur in man when 14.5 g guar is added to a Lundh type meal.16 Lower insulin and glucose levels may thus be due to food residues remaining in the small intestine longer to be absorbed more slowly. It is also possible that a proportion of the glucose might not be absorbed at all, but abdominal symptoms and production of flatus as a natural consequence of carbohydrate malabsorption 16 were not noticed by subjects at the time or during the
following 4-5
hours. In a few instances loose stools or increased amounts of flatus were produced in the evening or the following day. These delayed symptoms might be expected as a natural consequence of the slow breakdown of the fibre supplement by colonic bacteria, but the differences in response
,
between individuals was great. Finally there remains the possibility that guar and pectin may alter insulin secretion or insulin sensitivity. In experiments on non-diabetic volunteers no difference was seen in the insulin/glucose ratio during the rising phase of the glycaemia but from 45 to 90 min the test ratios fell below the controls-i.e., fibre appeared to reduce the insulin level required for a given bloodglucose level.9 A similar phenomenon was observed here: during the falling phase of the glycaemia (60-120 min) the insulin/glucose ratios after the high-fibre meals were significantly below those of the controls. However, such data are difficult to interpret in the non-steady state and also in the light of the lower bloodglucose values after the meal supplemented with fibre. Recently there has been considerable interest in the possible epidemiological association between the consumption of fibre-depleted or processed foods and the development of diabetes.3 17 The present work provides some experimental evidence that unabsorbable carbohydrates of plant origin, which together with lignin form what is termed dietary fibre, may decrease the glycaemia following an absorbable carbohydrate test meal without increasing peripheral blood-insulin levels. Increasing the quantity of such plant substances in the diets of diabetic patients might therefore in the long term decrease their insulin requirement. Control of metabolic changes following meals is a major problem in the management of diabetes. In this respect dietary fibre may well prove useful as an adjunct to insulin treatment or other forms of diabetic therapy by facilitating blood-glucose homoeostasis. We thank Sir Francis Avery Jones and Dr E. N. Rowlands for continuous encouragement; Mr Harold Godfrey, of Norgine Ltd, for supplying the guar flour; Mrs P. Evans for preparing the typescript; and Miss L. Hinks for performing the insulin assays. K. G. M. M. A. and T. D. R. H. thank the British Diabetic Association for financial support. M. A. G. is in receipt of a Wellcome fellowship. A. R. L. is in receipt of an M.R.C. training fellowship.
Requests for reprints should be addressed to D. J. A. J., M.R.C. Gastroenterology Unit, Central Middlesex Hospital, London NW10 7NS.
Preliminary Communication CIMETIDINE IN DUODENAL ULCER
Controlled Trial D. P. MAUDGAL W. S. BLACKWOOD D. LAWRENCE R. G. PICKARD T. C. NORTHFIELD Norman Tanner Gastroenterology Unit, St. James’s Hospital, and St. George’s Hospital Medical School, London
As part of a double-blind controlled clinical trial of cimetidine (1.6 g daily) in patients with endoscopically proven duodenal ulcer, repeat endoscopy has been carried out in 24 patients after two and/or six weeks’ treatment. At six weeks, 9 out of 11 patients on cimetidine and 3 out of 12 patients on placebo had healed (P
may have occurred after the high-fibre meal. Another, perhaps less obvious, factor which may be very important in explaining the results is the ability of fibre to limit diffusion towards the absorptive mucosal surface. 14 Both guar and pectin form gels or viscous solutions when hydrated. In vitro 1% guar gum in solution has been shown to inhibit by 40% the uptake of histidine by the everted intestinal sac of the rat." A twofold delay in mouth-to-caecum transit-time has also been shown to occur in man when 14.5 g guar is added to a Lundh type meal.16 Lower insulin and glucose levels may thus be due to food residues remaining in the small intestine longer to be absorbed more slowly. It is also possible that a proportion of the glucose might not be absorbed at all, but abdominal symptoms and production of flatus as a natural consequence of carbohydrate malabsorption 16 were not noticed by subjects at the time or during the
following 4-5
hours. In a few instances loose stools or increased amounts of flatus were produced in the evening or the following day. These delayed symptoms might be expected as a natural consequence of the slow breakdown of the fibre supplement by colonic bacteria, but the differences in response
,
between individuals was great. Finally there remains the possibility that guar and pectin may alter insulin secretion or insulin sensitivity. In experiments on non-diabetic volunteers no difference was seen in the insulin/glucose ratio during the rising phase of the glycaemia but from 45 to 90 min the test ratios fell below the controls-i.e., fibre appeared to reduce the insulin level required for a given bloodglucose level.9 A similar phenomenon was observed here: during the falling phase of the glycaemia (60-120 min) the insulin/glucose ratios after the high-fibre meals were significantly below those of the controls. However, such data are difficult to interpret in the non-steady state and also in the light of the lower bloodglucose values after the meal supplemented with fibre. Recently there has been considerable interest in the possible epidemiological association between the consumption of fibre-depleted or processed foods and the development of diabetes.3 17 The present work provides some experimental evidence that unabsorbable carbohydrates of plant origin, which together with lignin form what is termed dietary fibre, may decrease the glycaemia following an absorbable carbohydrate test meal without increasing peripheral blood-insulin levels. Increasing the quantity of such plant substances in the diets of diabetic patients might therefore in the long term decrease their insulin requirement. Control of metabolic changes following meals is a major problem in the management of diabetes. In this respect dietary fibre may well prove useful as an adjunct to insulin treatment or other forms of diabetic therapy by facilitating blood-glucose homoeostasis. We thank Sir Francis Avery Jones and Dr E. N. Rowlands for continuous encouragement; Mr Harold Godfrey, of Norgine Ltd, for supplying the guar flour; Mrs P. Evans for preparing the typescript; and Miss L. Hinks for performing the insulin assays. K. G. M. M. A. and T. D. R. H. thank the British Diabetic Association for financial support. M. A. G. is in receipt of a Wellcome fellowship. A. R. L. is in receipt of an M.R.C. training fellowship.
Requests for reprints should be addressed to D. J. A. J., M.R.C. Gastroenterology Unit, Central Middlesex Hospital, London NW10 7NS.
Preliminary Communication CIMETIDINE IN DUODENAL ULCER
Controlled Trial D. P. MAUDGAL W. S. BLACKWOOD D. LAWRENCE R. G. PICKARD T. C. NORTHFIELD Norman Tanner Gastroenterology Unit, St. James’s Hospital, and St. George’s Hospital Medical School, London
As part of a double-blind controlled clinical trial of cimetidine (1.6 g daily) in patients with endoscopically proven duodenal ulcer, repeat endoscopy has been carried out in 24 patients after two and/or six weeks’ treatment. At six weeks, 9 out of 11 patients on cimetidine and 3 out of 12 patients on placebo had healed (P
