Claus Thomsen

Effects on blood pressure, glucose, and lipid levels of a high-monounsaturated fat diet compared with a high-carbohydrate diet in NIDDM subjects.

OBJECTIVE To compare the influence on blood pressure, glucose, and lipid levels of a diet rich in monounsaturated fatty acids with an isocaloric, highcarbohydrate diet in 15 NIDDM subjects. RESEARCH DESIGN AND METHODS A crossover design with diet interventions and wash-out periods of 3 wk was applied. The patients were randomly assigned to a 3-wk treatment with a high-carbohydrate diet containing 50% of energy as carbohydrate and 30% of energy as fat (10% of energy as monounsaturated fatty acids) or an isocaloric diet with 30% of energy as carbohydrate and 50% of energy as fat (30% of energy as monounsaturated fatty acids). On the last day of the two diets, 24-h ambulatory blood pressure was measured and day profiles of glucose, hormones, and lipids were performed to a test menu rich in carbohydrates. RESULTS The diet rich in monounsaturated fat reduced daytime systolic (131 ± 3 vs. 137 ± 3 mmHg, P < 0.04) and 24-h systolic blood pressure (126 ± 8 vs. 130 ± 10 mmHg, P < 0.03) as well as daytime diastolic (78 ± 2 vs. 84 ± 2 mmHg, P < 0.02) and diurnal diastolic blood pressure (75 ± 6 vs. 78 ± 5 mmHg, P < 0.03) as compared with the high-carbohydrate diet. Evidence of lowered blood glucose levels on the high-monounsaturated diet compared with the highcarbohydrate diet were found with lower fasting blood glucose (6.1 ± 0.3 vs. 6.8 ± 0.5 mM, P < 0.05), lower average blood glucose levels (7.4 ± 0.5 vs. 8.2 ± 0.6 mM, P < 0.04), and peak blood glucose responses (9.9 ± 0.6 vs. 11.3 ± 0.7 mM, P < 0.02). The two diets had the same impact on lipid levels. CONCLUSIONS A diet rich in monounsaturated fat has beneficial effects on blood pressure and glucose metabolism, whereas no adverse effects on lipid composition in NIDDM subjects is detected.

Effect of Meal Frequency on Blood Glucose, Insulin, and Free Fatty Acids in NIDDM Subjects

Objective— We studied the effects of meal frequency on blood glucose, serum insulin, and FFAs in 12 NIDDM subjects. Research Design and Methods— Subjects were assigned in random order to two 8-hr observation periods after an overnight fast. They received isocaloric diets with similar composition either as six small or as two large meals. At the end of each study period, an IVGTT was given. Results— Two large meals induced an 84% greater maximum amplitude of glucose excursions than six small meals (6.1 ± 0.5 vs. 3.3 ± 0.5 mM, P < 0.005) and higher insulin responses (P < 0.03). The Kg response to an IVGTT did not differ in the two situations. The average FFA level was lowest in response to frequent meals (P < 0.02). Conclusions— A higher meal frequency acutely subdues glucose excursions and reduces insulin and FFA levels during the daytime in older NIDDM subjects.

Comparison of the effects of a monounsaturated fat diet and a high carbohydrate diet on cardiovascular risk factors in first degree relatives to type-2 diabetic subjects

Objective: Recent studies have demonstrated beneficial metabolic effects of dietary monounsaturated fatty acids (MUFA) in Type-2 diabetes mellitus (Type-2 DM). The question arises if dietary MUFA also has desirable effects on risk markers in subjects with high risk of developing Type-2 DM.Setting: University department of endocrinology.Subjects: Sixteen healthy, first-degree relatives (six men, 10 women, age (mean±s.d.): 35±2 years) with normal oral glucose tolerance tests.Interventions: Randomised study with two 4-week treatment periods with either a carbohydrate-rich (CHO) diet (55 E% carbohydrate, 30 E% fat, 15 E% protein) or a diet rich in olive oil [MUFA 40 E% fat (25 E% as MUFA), 45 E% carbohydrate, 15 E% protein]. The periods were divided by a 4-week wash-out period.Results: Similar lowering effects on total cholesterol, low density lipoprotein (LDL)-cholesterol, triglyceride and apoB levels were seen after the two diets. Slightly higher levels of high-density lipoprotein (HDL)-cholesterol (1.4±0.4 vs 1.3±0.4 mmol/l, P<0.0001) and apoA-1 (1.2±0.3 vs 1.1±0.3 mmol/l, P<0.05) were found in the MUFA-diet. Furthermore, the insulin sensitivity, as assessed by Bergman’s minimal model, and the first response insulin areas were similar, as were the 24-h blood pressures and the von Willebrand Factor (vWF) levels.Conclusions: Isocaloric diets rich in MUFA or rich in carbohydrate, respectively, seem to have similar effects on cardiovascular risk factors in persons at high risk of developing Type-2 DM. A potential risk, however, on body weight of high-fat diets should be kept in mind.Sponsorship: This study was supported by grants from the Danish Diabetes Association, Institute of Clinical Experimental Research, Aarhus University, The Danish Heart Foundation, The Danish Medical Research Council, Velux Foundation, Poul and Erna Sehested Hansens Foundation, Mogens Svarre Mogensens Foundation.

Incremental area under response curve more accurately describes the triglyceride response to an oral fat load in both healthy and type 2 diabetic subjects

Elevation of postprandial triacylglycerol (TG)-rich plasma lipoproteins is considered potentially atherogenic. Type 2 diabetic patients have exaggerated postprandial TG compared with healthy subjects. Postprandial TG responses to oral fat loads are usually studied as the area under the TG curve. No consensus exists regarding the method of choice when calculating the TG response area. We evaluated the correlation between fasting TG and postprandial TG responses calculated by the trapezoid rule as total area under the curve (AUC) and incremental area under the curve (iAUC). Furthermore, we compared the AUC and iAUC to a 3-point calculation method. Ten healthy subjects and 47 type 2 diabetic patients ingested test meals consisting of an energy-free soup plus 80 g fat and 50 g carbohydrate. TG responses were measured in total plasma, in a chylomicron (CM)-rich fraction and in a CM-poor fraction. In healthy subjects the AUC, but not iAUC, correlated positively to fasting TG. In type 2 diabetic patients a strong correlation was found between fasting TG and AUC, whereas weak associations were found to the iAUCs. The iAUC was strongly correlated to the postprandial TG rise in both groups. The 3-point areas differed significantly from the trapezoid measurements in both healthy and type 2 diabetic subjects. In conclusion, in both healthy and type 2 diabetic subjects total AUC is highly correlated to fasting TG, whereas iAUC more accurately describes the TG response to an oral fat load. The 3-point test seems less suitable for the determination of postprandial response in both healthy and type 2 diabetic subjects.

Effects of different fractions of whey protein on postprandial lipid and hormone responses in type 2 diabetes

Background/Objectives:Exacerbated postprandial lipid responses are associated with an increased cardiovascular risk. Dietary proteins influence postprandial lipemia differently, and whey protein has a preferential lipid-lowering effect. We compared the effects of different whey protein fractions on postprandial lipid and hormone responses added to a high-fat meal in type 2 diabetic subjects.Subjects/Methods:A total of 12 type 2 diabetic subjects ingested four isocaloric test meals in randomized order. The test meals contained 100 g of butter and 45 g of carbohydrate in combination with 45 g of whey isolate (iso-meal), whey hydrolysate (hydro-meal), α-lactalbumin enhanced whey (lac-meal) or caseinoglycomacropeptide enhanced whey (CGMP-meal). Plasma concentrations of triglyceride, retinyl palmitate, free fatty acid, insulin, glucose, glucagon, glucagon-like peptide 1 and glucose-dependent insulinotropic peptide were measured before and at regular intervals until 8-h postprandially.Results:We found no statistical significant differences between meals on our primary variable triglyceride. The retinyl palmitate response was higher after the hydro-meal than after the iso- and lac-meal in the chylomicron-rich fraction (P=0.008) while no significant differences were found in the chylomicron-poor fraction. The hydro- and iso-meal produced a higher insulin response compared with the lac- and CGMP-meal (P<0.001). Otherwise no significant differences in the hormone responses were found in the incremental area under the curve over the 480-min period.Conclusions:A supplement of four different whey protein fractions to a fat-rich meal had similar effects on postprandial triglyceride responses in type 2 diabetic subjects. Whey isolate and whey hydrolysate caused a higher insulin response.

Comparison of the Effects on the Diurnal Blood Pressure, Glucose, and Lipid Levels of a Diet Rich in Monounsaturated Fatty Acids With a Diet Rich in Polyunsaturated Fatty Acids in Type 2 Diabetic Subjects

The influence on blood pressure, glucose metabolism, and lipid levels of an exchange of polyunsaturated fatty acids with monounsaturated fatty acids in the diet was compared in 16 Type 2 diabetic outpatients. In a cross‐over study design the patients were randomly assigned to 3 weeks treatments with a diet containing 30% energy as monounsaturated fatty acids, or an isoenergetic diet with 30% energy as polyunsaturated fatty acids. The contents of total fat, satuarated fatty acids, cholesterol, and fibre were similar in the two diets. On the last days of the two diet periods, 24‐h ambulatory blood pressure was measured and the responses of glucose, hormones, and lipids to a carbohydrate rich test meal were measured. As compared with the polyunsaturated fatty acids diet, the monounsaturated fatty acids diet reduced 24‐h systolic (129 ± 11 vs 124 ± 8 mmHg (mean ± SD), p = 0.02) and diastolic blood pressure (76 ± 11 vs 73 ± 8 mmHg, p = 0.02). The two diets had similar, beneficial effects on glycaemic control, and cholesterol and lipoprotein concentrations. A diet rich in monounsaturated fatty acids has beneficial effects on the blood pressure, while similar effects on glucose and lipid levels are observed in normotensive Type 2 diabetic subjects.

Decrease in von Willebrand factor levels after a high-monounsaturated-fat diet in non-insulin-dependent diabetic subjects.

High levels of von Willebrand factor (vWF) have been reported in diabetics with vascular complications, suggesting a role for this protein in the development of cardiovascular complications in non-insulin-dependent diabetes mellitus (NIDDM). Recently, a diet rich in monounsaturated fatty acids (MUFA) has been found to improve glycemic control and decrease diurnal blood pressure as compared with a high-carbohydrate (H-CHO) diet in NIDDM subjects. To study the impact of MUFA on the hemostatic system, we compared the levels of vWF, fibrinogen, fibronectin, and alpha 2-macroglobulin before and after 3 weeks on a high-MUFA (H-MUFA) diet and on an isocaloric H-CHO diet in 15 NIDDM subjects. In a crossover study, the patients were randomly assigned to a H-CHO diet (50% carbohydrate, 30% fat [10% MUFA]) or a H-MUFA diet (30% carbohydrate, 50% fat [30% MUFA]). Before and on the last day of the two diets, vWF, fibrinogen, fibronectin, and alpha 2-macroglobulin levels were measured. The H-MUFA diet caused a decrease in vWF from 1.31 +/- 0.08 to 1.13 +/- 0.08 U/mL (P < .004), whereas an unchanged level was observed after a H-CHO diet (1.19 +/- 0.11 v 1.25 +/- 0.11 U/mL, NS). The relative changes in vWF during 3 weeks on a H-MUFA and on a H-CHO diet attained -12.5% +/- 3.2% versus 5.7% +/- 3.5%, respectively (P < .0001). Furthermore, unchanged levels of fibrinogen, fibronectin, and alpha 2-macroglobulin were seen after usage of the two diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute differential effects of dietary protein quality on postprandial lipemia in obese non-diabetic subjects.

Non-fasting triglyceridemia is much closer associated to cardiovascular risk compared to fasting triglyceridemia. We hypothesized that there would be acute differential effects of four common dietary proteins (cod protein, whey isolate, gluten, and casein) on postprandial lipemia in obese non-diabetic subjects. To test the hypothesis we conducted a randomized, acute clinical intervention study with crossover design. We supplemented a fat rich mixed meal with one of four dietary proteins i.e. cod protein, whey protein, gluten or casein. Eleven obese non-diabetic subjects (age: 40-68, body mass index: 30.3-42.0 kg/m(2)) participated and blood samples were drawn in the 8-h postprandial period. Supplementation of a fat rich mixed meal with whey protein caused lower postprandial lipemia (P = .048) compared to supplementation with cod protein and gluten. This was primarily due to lower triglyceride concentration in the chylomicron rich fraction (P = .0293). Thus, we have demonstrated acute differential effects on postprandial metabolism of four dietary proteins supplemented to a fat rich mixed meal in obese non-diabetic subjects. Supplementation with whey protein caused lower postprandial lipemia compared to supplementation with cod and gluten. As postprandial lipemia is closely correlated to cardiovascular disease, long-term dietary supplementation with whey protein may prove beneficial in preventing cardiovascular disease in obese non-diabetic subjects.

Comparison of a Carbohydrate-Rich Diet and Diets Rich in Stearic or Palmitic Acid in NIDDM Patients: Effects on lipids, glycemic control, and diurnal blood pressure

OBJECTIVE To compare the effects on lipid levels, glycemic control, and diurnal blood pressure of two diets rich in one of the two quantitatively most important saturated fatty acids, stearic and palmitic acid, with a carbohydrate-rich diet in NIDDM patients. RESEARCH DESIGN AND METHODS A total of 15 NIDDM patients participated in a randomized crossover study with three 3-week diet interventions separated by 2-week washout periods. Patients started with a diet rich in stearic acid (44 E% [percent of total energy] fat [13 E% stearic acid], 40 E% carbohydrate, 15 E% protein), palmitic acid (45 E% fat [16 E% palmitic acid], 40 E% carbohydrate, 15 E% protein), or carbohydrate (29 E% fat, 51 E% carbohydrate, and 18 E% protein), then were shifted to the other two diets in a randomized block design. At the start and end of each intervention period, fasting blood samples were drawn for analysis of lipids and blood glucose. In addition, diurnal blood pressure was measured. RESULTS At the end of the 3-week interventions, total cholesterol was significantly higher after the palmitic acid-rich diet than after the stearic acid-rich or carbohydrate-rich diets (5.3 ± 1.3 vs. 5.0 ± 1.2 and 4.9 ± 1.2 mmol/l, respectively; P = 0.03). No significant differences in triglyceride, LDL, or HDL cholesterol levels were seen after the three intervention diets. No difference in effects between the diet periods were seen for fructosamine, HbA1c, fasting blood glucose, or diurnal blood pressure. CONCLUSIONS For the first time, it has been demonstrated that a diet rich in palmitic acid was not as effective in lowering cholesterol levels as carbohydrate-rich and stearic acid-rich diets in NIDDM patients. No deleterious effects were seen on diurnal blood pressure, triglyceride levels, and glycemic control. Development of foods containing stearic acid rather than the more atherogenic saturated fatty acids may allow a wider choice of acceptable foods to NIDDM patients.

Differential Postprandial Lipoprotein Responses in Type 2 Diabetic Men with and without Clinical Evidence of a Former Myocardial Infarction

Postprandial lipemia plays an important role in the development of coronary heart disease through an elevation of triglyceride-rich lipoproteins. In type 2 diabetic male subjects, our aim was to compare postprandial lipemia in a high-risk population with former myocardial infarction (MI) with that of a lower risk population free of clinically detectable heart disease. 32 male type 2 diabetic subjects were included in the study. We matched 17 cases with a verified history of MI with 15 controls according to age, BMI, HbA1c, diabetes duration, smoking, and treatment of diabetes. Ongoing metformin, insulin, or lipid lowering pharmacological treatment were exclusion criteria. After a maximal exercise tolerance test and echocardiography, the subjects underwent a hyperinsulinemic, euglycemic clamp and a vitamin A fat loading test. Plasma triglyceride levels in the case group were significantly higher after 360 minutes (4.6 +/- 3.1 vs. 2.8 +/- 1.8 mmol/l, p = 0.04) and 480 minutes (3.6 +/- 2.2 vs. 2.4 +/- 2.4 mmol/l, p = 0.03), as was the incremental Area Under the Curve (iAUC) for the whole period (560 +/- 452 vs. 297 +/- 214 mmol x 480 min./l; p = 0.048). In addition, the retinyl palmitate responses in the chylomicron-fraction from the case group were significantly higher (iAUC 311,502 +/- 194,933 vs. 187,004 +/- 102,928 ng x 480 min./ml; p = 0.035). Type 2 diabetic males with prior MI had higher postprandial triglyceride-rich lipoprotein responses than those without MI, indicating that high responses may be a marker for a high-risk population.