BETAGLUKAN KLİNİK ÇALIŞMALAR

Betaglucare'in içerdiği yulaf betaglukan'ının kolesterol ve glicemik index düşürücü etkisi ile sindirim sistemi üzerindeki olumlu etkileri, yayınlanmış yüzün üzerinde bilimsel çalışmada gösterilmiştir. Aşağıda bunların arasından derlemiş çalışmaların bazılarını bulabilirsiniz:

Y. Granfeldt, L. Nyberg and I. Björk
European Journal of Clinical Nutrition (2008) 62, 600-607.

Conclusions: Muesli enriched with 4 g of b-glucans reduces postprandial glucose and insulin levels to a breakfast based on high glycaemic index products. A total of 4 g of b-glucans from oats seems to be a critical level for a significant decrease in glucose and insulin responses in healthy people.

Morvarid Kabir, Jean-Michel Oppert, Hubert Vidal, Francoise Bruzzo, Caroline Fiquet, Pierre Wursch, Gerard Slama, and Salwa W. Rizkalla
Metabolism, 51:819, 2002

Low-glycemic index diets are associated with a wide range of benefits when followed on a chronic basis. The chronic effects, however, of the substitution of 1 meal per day are not well known in diabetic subjects. Therefore, we aimed to evaluate whether the chronic use of a low-glycemic index breakfast (low-GIB) rich in low-GI carbohydrates and a modest amount of soluble fibers could have an effect on lipemia at a subsequent lunch, and improve glucose and lipid metabolism in men with type 2 diabetes. A total of 13 men with type 2 diabetes were randomly allocated in a double-blind cross-over design to a 4-week daily intake of a low-GI versus a high-GI breakfast separated by a 15-day washout interval. The low-GI breakfast was composed of whole grain bread and muesli containing 3 g ß-glucan from oats. Low-GIB induced lower postprandial plasma glucose peaks than the high-GIB at the beginning (baseline, P < .001) and after the 4-week intake (P < .001). The incremental area under the plasma glucose curve was also lower (P < .001, P < .01, baseline, and 4 weeks, respectively). There was no effect on fasting plasma glucose, insulin, fructosamine, or glycosylated hemoglobin (HbA1c). Fasting plasma cholesterol, as well as the incremental area under the cholesterol curve, were lower (P < .03, P < .02) after the 4-week low-GIB period than after the high-GIB period. Apolipoprotein B (apo B) was also decreased by the 4-week low-GIB. There was no effect of the low-GI breakfast on triacylglycerol excursions or glucose and insulin responses at the second meal. The high-GIB, however, tended to decrease the amount of mRNA of leptin in abdominal adipose tissue, but had no effect on peroxisome proliferator- activated receptor  (PPAR) and cholesterylester transfer protein (CETP) mRNA amounts. In conclusion, the intake of a low-GI breakfast containing a modest amount (3 g) of ß-glucan for 4 weeks allowed good glycemic control and induced low plasma cholesterol levels in men with type 2 diabetes. The decrease in plasma cholesterol associated with low-GI breakfast intake may reduce the risk of developing cardiovascular complications in subjects with type 2 diabetes.

Ripsin CM, Keenan JM, Jacobs DR Jr, Elmer PJ, Welch RR, Van Horn L, Liu K, Turnbull WH, Thye FW, Kestin M, et al.
JAMA 267(24):3317, 1992.

Objectives: To test the a priori hypothesis that consumption of oats will lower the blood total cholesterol level and to assess modifiers and confounders of this association.
Data Sources: A computerized literature (MEDLINE) search and the Quaker Oats Co identified published and unpublished trials as of March 1991. Raw data were requested for all trials.
Study Selection: Trials were included in summary effect size estimates if they were randomized and controlled, if a formal assessment of diet and body weight changes occurred, and, if raw data were not received, if there was enough information in the published report to perform calculations.
Data Synthesis: Twenty trials were identified. Using the methods of DerSimonian and Laird, a summary effect size for change in blood total cholesterol level of -0.13 mmol/L (-5.9 mg/dL) (95% confidence interval [CI], -0.19 to -0.017 mmol/L [-8.4 to -3.3 mg/dL]) was calculated for the 10 trials meeting the inclusion criteria. The summary effect size for trials using wheat control groups was -0.11 mmol/L (-4.4 mg/dL) (95% CI, -0.21 to -0.01 mmol/L [-8.3 to -0.38 mg/dL]). Calculation of Keys scores demonstrated that substituting carbohydrates for dietary fats and cholesterol did not account for the majority of blood cholesterol reduction. Larger reductions were seen in trials in which subjects had initially higher blood cholesterol levels (greater than or equal to 5.9 mmol/L [greater than or equal to 229 mg/dL]), particularly when a dose of 3 g or more of soluble fiber was employed.
Conclusion: This analysis supports the hypothesis that incorporating oat products into the diet causes a modest reduction in blood cholesterol level.

Battilana P, Ornstein K, Minehira K, Schwarz JM, Acheson K, Schneiter P, Burri J, Jéquier E, Tappy L.
European Journal of Clinical Nutrition (2201) 55, 327-333.

Administration of frequent meals with or without beta-glucan results in similar carbohydrate and lipid metabolism. This suggests that the lowered postprandial glucose concentrations which are observed after ingestion of a single meal containing beta-glucan are essentially due to a delayed and somewhat reduced carbohydrate absorption from the gut and do not result from the effects of fermentation products in the colon.

Marlett JA, Hosig KB, Vollendorf NW, Shinnick FL, Haack VS, Story JA.
Hepatology. 1994 Dec;20(6):1450-7.

Nine normolipidemic young men consumed a constant diet for 2 mo into which oat bran was incorporated during the second month so that we might test the hypotheses that oats lower serum cholesterol concentrations by decreasing bile acid and fat absorption and increasing bile acid synthesis. Bile acid kinetics were determined by measuring the 13C enrichment of serum cholic and chenodeoxycholic acids. Oat bran consumption decreased serum cholesterol levels (p < 0.01) and cholic acid pool size (p < 0.05). Deoxycholic acid pool size (p < 0.01) and the synthesis and fractional turnover rates of both primary bile acids (p < 0.05) increased. Total bile acid pool size did not change. Fecal excretion of total bile acids, the two secondary bile acids and fat increased significantly. The results demonstrate that oat bran lowers serum cholesterol levels in part by altering bile acid metabolism. In addition, the substantial increase in the proportion of the total bile acid pool that was deoxycholic acid is consistent with the hypothesis that oat bran also decreases cholesterol synthesis.