BACKGROUND: Although the pathogenesis of acne is currently unknown, recent epidemiologic studies of non-Westernized populations suggest that dietary factors, including the glycemic load, may be involved.

OBJECTIVE: The objective was to determine whether a low-glycemic-load diet improves acne lesion counts in young males.

DESIGN: Forty-three male acne patients aged 15-25 y were recruited for a 12-wk, parallel design, dietary intervention incorporating investigator-blinded dermatology assessments. The experimental treatment was a low-glycemic-load diet composed of 25% energy from protein and 45% from low-glycemic-index carbohydrates. In contrast, the control situation emphasized carbohydrate-dense foods without reference to the glycemic index. Acne lesion counts and severity were assessed during monthly visits, and insulin sensitivity (using the homeostasis model assessment) was measured at baseline and 12 wk.

RESULTS: At 12 wk, mean (+/-SEM) total lesion counts had decreased more (P=0.03) in the low-glycemic-load group (-23.5 +/- 3.9) than in the control group (-12.0 +/- 3.5). The experimental diet also resulted in a greater reduction in weight (-2.9 +/- 0.8 compared with 0.5 +/- 0.3 kg; P<0.001) and body mass index (in kg/m(2); -0.92 +/- 0.25 compared with 0.01 +/- 0.11; P=0.001) and a greater improvement in insulin sensitivity (-0.22 +/- 0.12 compared with 0.47 +/- 0.31; P=0.026) than did the control diet.

CONCLUSION: The improvement in acne and insulin sensitivity after a low-glycemic-load diet suggests that nutrition-related lifestyle factors may play a role in the pathogenesis of acne. However, further studies are needed to isolate the independent effects of weight loss and dietary intervention and to further elucidate the underlying pathophysiologic mechanisms.

BACKGROUND: Evidence from both animal and human studies suggests that abnormal glucose metabolism plays an important role in pancreatic carcinogenesis. We investigated whether diets high in foods that increase postprandial glucose levels are associated with an increased risk of pancreatic cancer.

METHODS: In a cohort of U.S. women (n = 88 802) participating in the Nurses' Health Study, 180 case subjects with pancreatic cancer were diagnosed during 18 years of follow-up. We used frequency of intake of individual foods as reported on a food-frequency questionnaire in 1980 to calculate sucrose, fructose, and carbohydrate intakes; glycemic index (postprandial blood glucose response as compared with a reference food); and glycemic load (glycemic index multiplied by carbohydrate content). Analyses of relative risk (RR) were performed by using multivariable Cox proportional hazards models to adjust for potential confounders. All statistical tests were two-sided.

RESULTS: Carbohydrate and sucrose intake were not associated with overall pancreatic cancer risk in this cohort. A statistically nonsignificant 53% increase in risk of pancreatic cancer (RR = 1.53, 95% confidence interval [CI] = 0.96 to 2.45) was observed among women with a high glycemic load intake, and a similar association was observed for fructose intake (RR = 1.57, 95% CI = 0.95 to 2.57). The associations of glycemic load and fructose intakes with pancreatic cancer risk were most apparent among women with elevated body mass index (>or=25 kg/m(2)) or with low physical activity. Among women who were both overweight and sedentary, a high glycemic load was associated with an RR of 2.67 (95% CI = 1.02 to 6.99; highest versus lowest quartile of intake; P for trend =.03), and high fructose was associated with an RR of 3.17 (95% CI = 1.13 to 8.91; P for trend =.04).

CONCLUSION: Our data support other findings that impaired glucose metabolism may play a role in pancreatic cancer etiology. A diet high in glycemic load may increase the risk of pancreatic cancer in women who already have an underlying degree of insulin resistance.

OBJECTIVES: Cardiovascular disease (CVD) is the leading cause of death in women. Hyperlipidemia is a major risk factor for CVD, but research suggests that metabolic syndrome and type 2 diabetes are also key factors in CVD in postmenopausal women. Most dietary programs, however, focus only on hyperlipidemia and not on insulin resistance associated with diabetes and metabolic syndrome. This 12-wk trial compared the effects of a dietary program combining a low glycemic index diet with a functional food delivering 30 g of soy protein and 4 g of phytosterols per day (LGID) with a standard dietary program (American Heart Association Step 1 diet; AHAD) in postmenopausal women.

METHODS: Fifty-nine postmenopausal women (average age 54.6 y, range 44-65 y) with a body mass index of 27 to 39 kg/m2 were randomly assigned to the LGID or the AHAD program for 12 wk. Total caloric intake and exercise were matched in each arm.

RESULTS: Twenty-seven women completed the LGID program, and 26 completed the AHAD program. The participants on the LGID program showed statistically significant decreases in total cholesterol (15.8%, P = 0.0036 between-group comparison), low-density lipoprotein cholesterol (14.8%, P = 0.004 between-group comparison), and triacylglycerol (44.8%, P = 0.006 between-group comparison). In addition, significant improvements were observed in ratios of total to high-density lipoprotein cholesterol and of triacylglycerol to high-density lipoprotein cholesterol, blood pressure, and Framingham risk assessment for coronary heart disease compared with the AHAD program.

CONCLUSIONS: A significantly greater improvement was observed in CVD risk factors in postmenopausal women on the LGID program (incorporating 30 g of soy protein and 4 g of phytosterols per day) than with a standard therapy.

Objective: The aim of this study was to compare the effects of different glycemic load diets on biochemical data and body composition, in overweight and obese subjects, during a 6-month period.

Research design and methods: This study was an experimental, randomized, parallel design. Anthropo-metric measurements and biochemical data were measured at baseline at 3 and at 6 months. All subjects completed 3-day dietary intake diaries at the baseline period and during the third and the sixth months. At the sixth month, LGL group had a mean intake of 1,360± 300 kcal/day and the high glycemic load group (HGL) had a mean intake of 1,544 ± 595 kcal/day.

Results: LGL group obtained a weight reduction of 4.5% (p = 0.006) and the HGL group of 3.0% (p = 0.18). Significant reductions in waist circumference (5%, p = 0.001) of the LGL group were observed, 10% of body fat percentage (p = 0.001), 4.3 kg (13%) of body fat (p = 0.001), 14% of total cholesterol (p=0.007), 35% of high-density lipoproteins (HDL) (p = 0.001), and 10% of HOMA (p = 0.009). In the HGL group, reductions of 4.5% of waist circumference (p = 0.02), 37% of HDL (p = 0.002), and an increase of 8 % of LDL (p = 0.04) were observed.

Conclusions: These results suggest that long term LGL diets are more effective for reducing body mass index, body fat, waist circumference and HOMA and, therefore, may contribute in the prevention of diabetes.

OBJECTIVES:This study evaluated the glycemic, insulinemic, and glucagon-like peptide-1 (GLP-1) responses of subjects with type 2 diabetes mellitus to consumption of two diabetes-specific tube-feeding formulas (slowly digested carbohydrate formula [SDC] and diabetes-specific formula [DSF]) and one formula intended for individuals without diabetes (standard formula [STND]).

METHODS:Forty-eight subjects controlled with diet and/or oral antihyperglycemic medications received the SDC, DSF, and STND. Postprandial glucose, insulin, and GLP-1 were measured on three occasions after an overnight fast in a double-blinded, randomized, three-treatment, crossover design.

RESULTS:The positive area under the curve for glucose and insulin with the STND was higher (P<0.001) compared with the SDC and DSF. The adjusted GLP-1 concentration at 60 min was higher for the SDC compared with the DSF and STND (P<0.05).

CONCLUSION:Both lower-carbohydrate diabetes-specific formulas resulted in a lower postprandial blood glucose response compared with the STND. The formula also rich in slowly digested carbohydrate and monounsaturated and omega-3 fatty acids (SDC) produced significantly lower blood glucose and insulin responses and higher levels of GLP-1 in the presence of significantly lower insulin concentrations. These results support the view that the quantity and quality of carbohydrate and fat may play important roles in the management of patients with type 2 diabetes mellitus and could result in improved beta-cell function over the long term.

OBJECTIVES: This randomized controlled study was conducted to determine the effect of low glycemic index (GI) dietary advice on eating patterns and dietary quality in Asian patients with type 2 diabetes (T2DM).

METHODS: Asian patients with T2DM (N =  104) were randomized into 2 groups that received either low GI or conventional carbohydrate exchange (CCE) dietary advice for 12 weeks. Nutritional prescriptions were based on the medical nutrition therapy for T2DM, with the difference being in the GI component of the carbohydrates. Dietaryintake and food choices were assessed with the use of a 3-day food record.

RESULTS: At week 12, both groups achieved the recommendations for carbohydrate (52 ± 4% and 54 ± 4% of energy) and fat (30 ± 4% and 28 ± 5% of energy) intake. There were no significant differences in the reported macronutrient intake in both groups. With the low GI diet, crude fiber and dietary calcium intake increased, while the dietary GI reduced. Subjects in the lowest dietary glycemic index/glycemic load (GI/GL) quartile consumed more parboiled/basmati rice, pasta, milk/dairy products, fruits, and dough, which are foods from the low GI category. There was a significant reduction in the hemoglobin A(1c) level at week 12 for patients in the lowest GI/GL quartile (Δ  =  -0.7 ± 0.1%) compared with those in the highest GI/GL quartile (Δ  =  -0.1 ± 0.2%).

CONCLUSIONS: These results demonstrate the ability of low GI dietary advice to improve the dietary quality of Asian patients with T2DM.

Nutritional habits modifications have shown an important impact in preventing and ameliorating metabolic alterations, such as nonalcoholic fatty liver disease (NAFLD). Among several dietary approaches that exert positive effects in NAFLD patients, the Mediterranean dietary pattern has shown notable benefits. This review explores the molecular mechanisms through which the Mediterranean diet would improve risk factors associated with metabolic syndrome and NAFLD. The main features of the Mediterranean diet acting on metabolism are represented by its whole-grain and low glycemic index cereal-based items, its fatty acid profile, and its content in phytochemical compounds. Carbohydrate-rich foods high in dietary fiber inducing low glycemic response are able to interact with glucose and insulin metabolism. Unsaturated fatty acids are associated with better hepatic lipid metabolism. Finally, phytochemical compounds, such as dietary polyphenols, are thought to ameliorate inflammation, which is considered one of the mechanisms through which NALFD may evolve into nonalcoholic steatohepatitis (NASH).

OBJECTIVES:Diets that induce a high glycemic response might increase the risk of biliary tract cancer (BTC). We evaluated the hypothesis that diets with high glycemic load (GL) and high glycemic index (GI), which are measures of the glycemic effect of foods, are associated with an increased incidence of BTC.

METHODS:We used data from a population-based prospective study of 76,014 Swedish adults (age 45-83 years; 57% men) who were free of cancer and had completed a food-frequency questionnaire in the autumn of 1997. Incident cancer cases were ascertained by linkage with the Swedish Cancer Registry. Data were analyzed using Cox proportional hazards regression models.

RESULTS:During a mean follow-up of 13.3 years (1,010,777 person-years), we identified 140 extrahepatic BTC cases (including 77 gallbladder cancers) and 23 intrahepatic BTC cases. A high dietary GL was associated with an increased risk of BTC. The multivariable relative risks for the highest versus lowest quartile of dietary GL were 1.63 (95% confidence interval (95% CI), 1.01-2.63) for extrahepatic BTC, 2.14 (95% CI, 1.06-4.33) for gallbladder cancer, and 3.46 (95% CI, 1.22-9.84) for intrahepatic BTC. Dietary GI was statistically significantly positively associated with risk of extrahepatic BTC and gallbladder cancer. We observed no statistically significant association between carbohydrate intake and BTC risk, although all associations were positive.

CONCLUSION:Although these data do not prove a causal relationship, they are consistent with the hypothesis that high-GL and high-GI diets are associated with an increased risk of BTC.