One-Year Comparison of a High–Monounsaturated Fat Diet With a High-Carbohydrate Diet in Type 2 Diabetes A MUFA-Rich Diet Improves Posprandial Glucose, Lipid and GLP-1 Responses in Insulin-Resistant Subjects Intake of a Diet High in Trans Monounsaturated Fatty Acids or Saturated Fatty Acids: Effects on postprandial insulinemia and glycemia in obese patients with NIDDM Comparison of the effects on insulin resistance and glucose tolerance of 6-mo high-monounsaturated-fat, low-fat, and control diets. Comparison of 3 ad libitum diets for weight-loss maintenance, risk of cardiovascular disease, and diabetes: a 6-mo randomized, controlled trial. Comparison of high- and low-glycemic-index breakfast cereals with monounsaturated fat in the long-term dietary management of type 2 diabetes. Comparison of a high-carbohydrate and a high-monounsaturated fat, olive oil-rich diet on the susceptibility of LDL to oxidative modification in subjects with Type 2 diabetes mellitus. Effect of energy restriction, weight loss, and diet composition on plasma lipids and glucose in patients with type 2 diabetes. Dietary strategies for patients with type 2 diabetes in the era of multi-approaches; review and results from the Dietary Intervention Randomized Controlled Trial (DIRECT). Randomized Controlled Trial of a MUFA or Fiber-Rich Diet on Hepatic Fat in Prediabetes Effects of High-monounsaturated Fatty Acid Enteral Formula versus High-carbohydrate Enteral Formula on Plasma Glucose Concentration and Insulin Secretion in Healthy Individuals and Diabetic Patients Long-term effect of varying the source or amount of dietary carbohydrate on postprandial plasma glucose, insulin, triacylglycerol, and free fatty acid concentrations in subjects with impaired glucose tolerance. Adverse effects on insulin secretion of replacing saturated fat with refined carbohydrate but not with monounsaturated fat: A randomized controlled trial in centrally obese subjects. A randomised controlled trial of the effect of low fat diet advice on dietary response in insulin independent diabetic women Comparison of low- and high-carbohydrate diets for type 2 diabetes management: a randomized trial. Comparison of a high-carbohydrate diet with a high-monounsaturated-fat diet in patients with non-insulin-dependent diabetes mellitus. Clinical Efficacy of Two Hypocaloric Diets That Vary in Overweight Patients With Type 2 Diabetes
OBJECTIVE —The purpose of this study was to compare the effects of high – monounsaturated fatty acid ( MUFA ) and high-carbohydrate ( CHO ) diets on body weight and glycemic control in men and women with type 2 diabetes . RESEARCH DESIGN AND METHODS —Overweight/obese participants with type 2 diabetes ( n = 124 , age = 56.5 ± 0.8 years , BMI = 35.9 ± 0.3 kg/m2 , and A1C = 7.3 ± 0.1 % ) were r and omly assigned to 1 year of a high-MUFA or high-CHO diet . Anthropometric and metabolic parameters were assessed at baseline and after 4 , 8 , and 12 months of dieting . RESULTS —Baseline characteristics were similar between the treatment groups . The overall retention rate for 1 year was 77 % ( 69 % for the high-MUFA group and 84 % for the high-CHO group ; P = 0.06 ) . Based on food records , both groups had similar energy intake but a significant difference in MUFA intake . Both groups had similar weight loss over 1 year ( −4.0 ± 0.8 vs. −3.8 ± 0.6 kg ) and comparable improvement in body fat , waist circumference , diastolic blood pressure , HDL cholesterol , A1C , and fasting glucose and insulin . There were no differences in these parameters between the groups . A follow-up assessment of a subset of participants ( n = 36 ) was conducted 18 months after completion of the 52-week diet . These participants maintained their weight loss and A1C during the follow-up period . CONCLUSIONS —In individuals with type 2 diabetes  , high-MUFA diets are an alternative to conventional lower-fat , high-CHO diets with comparable beneficial effects on body weight , body composition , cardiovascular risk factors , and glycemic control Objective : To study the effects of three weight-maintenance diets with different macronutrient composition on carbohydrate , lipid metabolism , insulin and incretin levels in insulin-resistant subjects . Methods : A prospect i ve study was performed in eleven ( 7 W , 4 M ) offspring of obese and type 2 diabetes patients . Subjects had a BMI > 25 Kg/m2 , waist circumference ( men/women ) > 102/88 , HBA1c < 6.5 % and were regarded as insulin-resistant after an OGTT ( Matsuda ISIm < 4 ) . They were r and omly divided into three groups and underwent three dietary periods each of 28 days in a crossover design : a ) diet high in saturated fat ( SAT ) , b ) diet rich in monounsaturated fat ( MUFA ; Mediterranean diet ) and c ) diet rich in carbohydrate ( CHO ) . Results : Body weight and resting energy expenditure did not changed during the three dietary periods . Fasting serum glucose concentrations fell during MUFA-rich and CHO-rich diets compared with high-SAT diets ( 5.02 ± 0.1 , 5.03 ± 0.1 , 5.50 ± 0.2 mmol/L , respectively . Anova < 0.05 ) . The MUFA-rich diet improved insulin sensitivity , as indicated by lower homeostasis model analysis -insulin resistance ( HOMA-ir ) , compared with CHO-rich and high-SAT diets ( 2.32 ± 0.3 , 2.52 ± 0.4 , 2.72 ± 0.4 , respectively , Anova < 0.01 ) . After a MUFA-rich and high-SAT breakfasts ( 443 kcal ) the postpr and ial integrated area under curve ( AUC ) of glucose and insulin were lowered compared with isocaloric CHO-rich breakfast ( 7.8 ± 1.3 , 5.84 ± 1.2 , 11.9 ± 2.7 mmol · 180 min/L , Anova < 0.05 ; and 1004 ± 147 , 1253 ± 140 , 2667 ± 329 pmol · 180 min/L , Anova < 0.01 , respectively ) ; while the integrated glucagon-like peptide-1 response increased with MUFA and SAT breakfasts compared with isocaloric CHO-rich meals ( 4.22 ± 0.7 , 4.34 ± 1.1 , 1.85 ± 1.1 , respectively , Anova < 0.05 ) . Fasting and postpr and ial HDL cholesterol concentrations rose with MUFA-rich diets , and the AUCs of triacylglycerol fell with the CHO-rich diet . Similarly fasting proinsulin ( PI ) concentration fell , while stimulated ratio PI/I was not changed by MUFA-rich diet . Conclusions : Weight maintenance with a MUFA-rich diet improves HOMA-ir and fasting proinsulin levels in insulin-resistant subjects . Ingestion of a virgin olive oil-based breakfast decreased postpr and ial glucose and insulin concentrations , and increased HDL-C and GLP-1 concentrations as compared with CHO-rich diet OBJECTIVE High intake of trans fatty acids and saturated fatty acids ( SFAs ) is known to increase the risk of coronary heart disease . We studied the effects of diets enriched in various fatty acids on postpr and ial insulinemia and fasting serum levels of lipids and lipoproteins in obese patients with NIDDM . RESEARCH DESIGN AND METHODS Sixteen obese NIDDM patients were studied in a free-living outpatient regimen . After a run-in period , the patients received three different isocaloric diets for 6 weeks using a r and omized crossover design . The patients were instructed to keep the energy intake from carbohydrate and protein constant at 50 and 20 E% ( percent of energy intake ) , respectively , on all three diets . The fat composition of the diets differed : saturated fat ( SAT ) diet ( 20 E% SFAs , 5 E% polyunsaturated fatty acids [ PUFAs ] , and 5 E% monounsaturated fatty acids [ MUFAs ] ) versus cis monounsaturated fatty acid ( CMUFA ) diet ( 20 E% cis-MUFAs , 5 E% PUFAs , and 5 E% SFAs ) versus trans monounsaturated fatty acid ( TMUFA ) diet ( 20 E% trans-MUFAs , 5 E% PUFAs , and 5 E% SFAs ) . Fasting serum levels of lipids and lipoproteins were measured at baseline and in the fasting state before meal tolerance tests at the end of each study period . Insulin secretion was assessed from incremental serum insulin and C-peptide responses during the meal tests . RESULTS BMI , waist-to-hip ratio , and glycemic control remained stable throughout the study . After meal stimulation , postpr and ial glycemic responses were similar on all diets ; however , serum insulin and C-peptide responses were greater following the TMUFA and SAT diets than following the baseline or CMUFA diets ( P < 0.05 ) . No statistical difference was found in fasting levels of serum lipids ( total cholesterol , triglyceride , phospholipid , and nonesterified fatty acids ) or lipoproteins of HDL cholesterol , VLDL cholesterol , LDL cholesterol , and apolipoprotein B between diets . CONCLUSIONS In the presence of unchanged glycemia , both dietary trans fatty acids and SFAs induce an increase in postpr and ial insulinemia in obese patients with NIDDM BACKGROUND The effect of dietary fat and carbohydrate on glucose metabolism has been debated for decades . OBJECTIVE The objective was to compare the effect of 3 ad libitum diets , different in type and amount of fat and carbohydrate , on insulin resistance and glucose tolerance subsequent to weight loss . DESIGN Forty-six nondiabetic , obese [ mean ( + /-SEM ) body mass index ( in kg/m(2 ) ) : 31.2 + /- 0.3 ] men ( n = 20 ) and premenopausal women ( n = 26 ) aged 28.0 + /- 0.7 y were r and omly assigned to 1 of 3 diets after > or = 8 % weight loss : 1 ) MUFA diet ( n = 16 ) : moderate in fat ( 35 - 45 % of energy ) and high in monounsaturated fatty acids ( > 20 % of energy ) ; 2 ) LF diet ( n = 18 ) : low-fat diet ( 20 - 30 % of energy ) , and 3 ) control diet ( n = 12 ) : 35 % of energy as fat ( > 15 % of energy as saturated fatty acids ) . Protein accounted for 15 % of energy in all 3 diets . A 2-h oral-glucose-tolerance test ( OGTT ) was performed before and after the 6-mo dietary intervention . All foods were provided by a purpose -built supermarket . RESULTS After 6 mo , the MUFA diet reduced fasting glucose ( -3.0 % ) , insulin ( -9.4 % ) , and the homeostasis model assessment of insulin resistance score ( -12.1 % ) . Compared with the MUFA diet , the control diet increased these variables [ 1.4 % ( P = 0.014 ) , 21.2 % ( P = 0.030 ) , and 22.8 % ( P = 0.015 ) , respectively ] , as did the LF diet [ 1.4 % ( P = 0.090 ) , 13.1 % ( P = 0.078 ) , and 15.5 % ( P = 0.095 ) , respectively ] . No significant group differences were detected in glucose or insulin concentrations during the OGTT , in the Matsudas index , in body weight , or in body composition . CONCLUSION A diet high in monounsaturated fat has a more favorable effect on glucose homeostasis than does the typical Western diet in the short term and may also be more beneficial than the official recommended low-fat diet during a period of weight regain subsequent to weight loss BACKGROUND The optimal dietary content and type of fat and carbohydrate for weight management has been debated for decades . OBJECTIVE The objective was to compare the effects of 3 ad libitum diets on the maintenance of an initial weight loss of > or=8 % and risk factors for CVD and diabetes during a 6-mo controlled dietary intervention . DESIGN Nondiabetic overweight or obese [ mean + /- SD body mass index ( in kg/m(2 ) ) : 31.5 + /- 2.6 ] men ( n = 55 ) and women ( n = 76 ) aged 28.2 + /- 4.8 y were r and omly assigned to a diet providing a moderate amount of fat ( 35 - 45 % of energy ) and > 20 % of fat as monounsaturated fatty acids ( MUFA diet ; n = 54 ) , to a low-fat ( 20 - 30 % of energy ) diet ( LF diet ; n = 51 ) , or to a control diet ( 35 % of energy as fat ; n = 26 ) . Protein constituted 10 - 20 % of energy in all 3 diets . All foods were provided free of charge from a purpose -built supermarket . RESULTS More subjects dropped out of the MUFA ( 28 % ) group than out of the LF group ( 16 % ) and control group ( 8 % ) ( MUFA compared with control : P < 0.05 ) . All groups regained weight ( MUFA : 2.5 + /- 0.7 kg ; LF : 2.2 + /- 0.7 kg ; and control : 3.8 + /- 0.8 kg ; NS ) . Body fat regain was lower in the LF ( 0.6 + /- 0.6 % ) and MUFA ( 1.6 + /- 0.6 % ) groups than in the control group ( 2.6 + /- 0.5 % ) ( P < 0.05 ) . In the MUFA group , fasting insulin decreased by 2.6 + /- 3.5 pmol/L , the homeostasis model assessment of insulin resistance by 0.17 + /- 0.13 , and the ratio of LDL to HDL by 0.33 + /- 0.13 ; in the LF group , these variables increased by 4.3 + /- 3.0 pmol/L ( P < 0.08 ) and 0.17 + /- 0.10 ( P < 0.05 ) and decreased by 0.02 + /- 0.09 ( P = 0.005 ) , respectively ; and in the control group , increased by 14.0 + /- 4.3 pmol/L ( P < 0.001 ) , 0.57 + /- 0.17 ( P < 0.001 ) , and 0.05 + /- 0.14 ( P = 0.036 ) , respectively . Dietary adherence was high on the basis of fatty acid changes in adipose tissue . CONCLUSIONS Diet composition had no major effect on preventing weight regain . However , both the LF and MUFA diets produced less body fat regain than did the control diet , and the dropout rate was lowest in the LF diet group , whereas fasting insulin decreased and the homeostasis model assessment of insulin resistance and ratio of LDL to HDL improved with the MUFA diet . This trial was registered at clinical trials.gov as NCT00274729 BACKGROUND Results of 6-wk studies suggest that high-carbohydrate diets are deleterious for people with type 2 diabetes . OBJECTIVE Our objective was to see whether long-term replacement of dietary monounsaturated fatty acids ( MUFAs ) with carbohydrate from breakfast cereals with either a high or a low glycemic index ( GI ) affected blood glucose and lipids in subjects with type 2 diabetes . DESIGN Subjects with type 2 diabetes ( n = 91 ) were r and omly assigned to receive approximately 10 % of energy from a low-GI breakfast cereal , a high-GI cereal , or oil or margarine containing MUFA for 6 mo . Eating breakfast cereal was prohibited for subjects in the MUFA group . RESULTS Seventy-two subjects completed the trial . The subjects who received cereals consumed approximately 10 % more energy from carbohydrate than did the subjects in the MUFA group . Changes in glycated hemoglobin , body weight , and fasting cholesterol and triacylglycerol did not differ significantly among groups . HDL cholesterol increased by approximately 10 % in the MUFA group compared with subjects who consumed either high- or low-GI cereals ( P = 0.002 ) . The ratio of total to HDL cholesterol was higher in the subjects who consumed the high-GI cereal than in the MUFA group at 3 mo but not at 6 mo ( diet x time interaction , P = 0.041 ) . During 8-h metabolic profiles , mean plasma insulin was higher and mean free fatty acids were lower in the 2 cereal groups than in the MUFA group ( P < 0.05 ) . CONCLUSIONS A 10 % increase in carbohydrate intake associated with breakfast cereal consumption had no deleterious effects on glycemic control or blood lipids over 6 mo in subjects with type 2 diabetes . The increase in plasma insulin and the reduction in free fatty acids associated with higher carbohydrate intake may reduce the rate of progression of diabetes AIMS To compare the effects of a high-carbohydrate ( CHO ) diet and a high-monounsaturated fatty acid ( MUFA ) diet on LDL oxidative resistance in free-living individuals with Type 2 diabetes mellitus . METHODS Twenty-two men and women out- patients with Type 2 diabetes , with mean age 61 years and in fair metabolic control ( HbA1c<8.0 % ) , were enrolled at a university hospital lipid clinic in a r and omized , crossover feeding trial comparing two isocaloric diets for 6 weeks each : CHO ( fat , 28 % energy ) and MUFA ( fat , 40 % energy ) based on virgin olive oil . Outcome measurements were changes in LDL susceptibility to oxidation , body weight , glycaemic control , and lipoprotein profiles . RESULTS Planned and observed diets were well matched . Participants preferred the MUFA diet over the CHO diet . The lag time of conjugated diene formation during Cu2 + -induced LDL oxidation was similar after the CHO and MUFA diets ( 36.4 + /- 12.2 min and 36.0 + /- 13.7 min , respectively ) . Body weight , glycaemic control , total triglycerides , and total , LDL- and HDL-cholesterol levels also were similar after the two diets . Compared with the CHO diet , the MUFA diet lowered VLDL-cholesterol by 35 % ( P=0.023 ) and VLDL triglyceride by 16 % ( P=0.016 ) . CONCLUSIONS Natural food-based high-CHO and high-MUFA diets have similar effects on LDL oxidative resistance and metabolic control in subjects with Type 2 diabetes . A MUFA diet is a good alternative to high-CHO diets for nutrition therapy of diabetes because it also has a beneficial effect on the lipid profile and superior patient acceptance OBJECTIVE To determine the optimal diet for improving glucose and lipid profiles in obese patients with type 2 diabetes during moderate energy restriction . RESEARCH DESIGN AND METHODS A total of 35 free-living obese patients with type 2 diabetes were assigned to one of three 1,600 kcal/day diets for 12 weeks . The diets were high carbohydrate ( 10 % fat , 4 % saturated ) , high monounsaturated fat ( MUFA ) ( 32 % fat , 7 % saturated ) , or high saturated fat ( SFA ) ( 32 % fat , 17 % saturated ) . RESULTS Diet composition did not affect the magnitude of weight loss , with subjects losing an average of 6.6 + /- 0.9 kg . Energy restriction and weight loss result ed in reductions in fasting plasma glucose ( -14 % ) , insulin ( -27 % ) , GHb ( -14 % ) , and systolic ( -7 % ) and diastolic blood pressure ( -10 % ) levels and the glucose response area ( -17 % ) independent of diet composition . Diet composition did affect the lipoprotein profile . LDL was 10 % and 17 % lower with the high-carbohydrate and high-MUFA diets , respectively , whereas no change was observed with the high-SFA diet ( P < 0.001 for effect of diet ) . HDL was transiently reduced on the high-carbohydrate diet at weeks 1 , 4 , and 8 , whereas higher fat consumption maintained these levels . The total cholesterol : HDL ratio , although significantly reduced on the high-MUFA diet ( P < 0.01 ) , was not different from the other two diets after adjustment for baseline differences . CONCLUSIONS Energy restriction , independent of diet composition , improves glycemic control ; however , reducing SFA intake by replacing SFA with carbohydrate or MUFA reduces LDL maximally during weight loss and to a greater degree than has been shown in weight-stable studies Dietary intervention is recognized as a key component in prevention and management of type 2 diabetes ( T2DM ) and the debate persists : which dietary strategy is most effective . In the Dietary Intervention R and omized Controlled Trial ( DIRECT ) 322 moderately obese participants were r and omized for 2 years to one of three diet groups : low-fat , Mediterranean and low-carbohydrate . Differential effects were observed in the sub-group of patients with T2DM at 24 months : participants r and omized to the Mediterranean diet , which had the highest intake of dietary fibers and unsaturated to saturated fat ratio , achieved greater significant improvements in fasting plasma glucose and insulin levels . Patients who were r and omized to the low-carbohydrate diet , which had the minimal intake of carbohydrates , achieved a significant reduction of hemoglobin A1C . Although improvements were observed in all groups , the low-fat diet was likely to be less beneficial in terms of glycemic control and lipid metabolism . Interpretation of results from different studies on dietary strategies may be complex since there is often no consistency in diet compositions , calorie restriction , intensity of intervention , dietary assessment or extent of adherence in the trial . Nevertheless , it seems that low fat restricted calorie diets are effective for weight loss and are associated with some metabolic benefits ; however , some recent trials have shown that low carbohydrate diets are as efficient in inducing weight loss and in some metabolic measures such as serum triglycerides and HDL-cholesterol may be even superior to low fat diets . When addressing the issue of diet quality rather than quantity applying the glycemic index may have some added benefits . Furthermore special features of the Mediterranean diet have apparent additional favorable effects for patients with T2DM Context Increased prevalence of type 2 diabetes mellitus and prediabetes worldwide is attributed in part to an unhealthy diet . Objective To evaluate whether 12 weeks of high monounsaturated fatty acid ( MUFA ) or fiber-rich weight-maintenance diet lowers hepatic fat and improves glucose tolerance in people with prediabetes . Design Subjects underwent a [ 6 , 6 - 2H2]-labeled 75-g oral glucose tolerance test to estimate hepatic insulin sensitivity and liver fat fraction ( LFF ) using magnetic resonance spectroscopy before and after intervention . Setting Mayo Clinic Clinical Research Trials Unit . Participants 43 subjects with prediabetes . Intervention Subjects were r and omized into three isocaloric weight-maintaining diets containing MUFA ( olive oil ) , extra fiber , and st and ard US food ( control-habitual diet ) . Outcome Measures LFF , glucose tolerance , and indices of insulin action and secretion . Results Body weight was maintained constant in all groups during the intervention . Glucose and hormonal concentrations were similar in all groups before , and unchanged after , 12 weeks of intervention . LFF was significantly lower after intervention in the MUFA group ( P < 0.0003 ) but remained unchanged in the fiber ( P = 0.25 ) and control groups ( P = 0.45 ) . After 12 weeks , LFF was significantly lower in the MUFA than in the control group ( P = 0.01 ) , but fiber and control groups did not differ ( P = 0.41 ) . Indices of insulin action and secretion were not significantly different between the MUFA and control groups after intervention ( P ≥ 0.11 ) , but within-group comparison showed higher hepatic ( P = 0.01 ) and total insulin sensitivity ( P < 0.04 ) with MUFA . Conclusions Twelve weeks of a MUFA diet decreases hepatic fat and improves both hepatic and total insulin sensitivity We investigated the effects of high-monounsaturated fatty acid ( MUFA ) versus high-carbohydrate enteral formula on post-pr and ial plasma glucose concentration and insulin response in Japanese patients with type 2 diabetes mellitus and healthy Japanese volunteers . Ten healthy volunteers aged 20.8 ± 1.2 years and 12 diabetic patients with good glycaemic control ( glycosylated haemoglobulin < 7 % ) aged 58.6 ± 7.7 years were r and omly assigned to take high-MUFA or high-carbohydrate formula after a 12-h overnight fast . The patients switched to the other formula after 7 days . Post-pr and ial plasma glucose and insulin response were significantly lower in all subjects after taking high-MUFA formula compared with high-carbohydrate formula . No differences were observed in free fatty acids , triglycerides and plasma glucagon between the two diet groups . In conclusion , a high-MUFA enteral formula  suppresses post-pr and ial hyperglycaemia without exaggerated insulin secretion compared with a high-carbohydrate enteral diet in patients with type 2 diabetes and healthy subjects BACKGROUND Reducing the glycemic load ( GL ) is considered beneficial for managing insulin resistance . The GL can be reduced either by reducing carbohydrate intake or by reducing the glycemic index ( GI ) . OBJECTIVE We studied whether these 2 dietary maneuvers have the same long-term effects on postpr and ial plasma glucose , insulin , triacylglycerol , and free fatty acid ( FFA ) concentrations in subjects with impaired glucose tolerance ( IGT ) . DESIGN Thirty-four subjects with IGT were r and omly assigned to high-carbohydrate , high-GI ( high-GI ) ; high-carbohydrate , low-GI ( low-GI ) ; and low-carbohydrate , high-monounsaturated fatty acid ( MUFA ) diets for 4 mo . Plasma glucose , insulin , and FFAs were measured from 0800 to 1600 at baseline in response to high-GI meals ( 60 % carbohydrate , GI = 61 , GL = 63 ) and after 4 mo in response to meals representative of the study diet . RESULTS Carbohydrate intake ( % of energy ) , GI , and GL in the high-GI , low-GI , and MUFA groups ( breakfast and lunch meals combined ) , respectively , were 60 % , 61 , and 63 ; 60 % , 53 , and 55 ; and 49 % , 61 , and 52 . Compared with the change after 4 mo of the high-GI diet , both the low-GI and MUFA diets reduced 0 - 8-h mean plasma glucose concentrations by 0.35 mmol/L ( P < 0.05 ) . Mean plasma insulin was approximately 20 % higher ( P < 0.05 ) and FFAs approximately 12 % lower ( P < 0.05 ) after the low-GI diet than after the high-GI diet , with no significant effect of MUFA . Changes in 0 - 8-h mean plasma triacylglycerols in the 3 treatment groups differed significantly : -0.14 , 0.04 , and 0.18 mmol/L , respectively , with the high-GI , MUFA , and low-GI diets . CONCLUSIONS In subjects with IGT , reducing the GI of the diet for 4 mo reduced postpr and ial plasma glucose by the same amount as did reducing carbohydrate intake . The 2 dietary maneuvers had different effects on postpr and ial plasma insulin , triacylglycerols , and FFAs BACKGROUND Current dietary guidelines recommend the replacement of saturated fatty acids ( SAFAs ) with carbohydrates or monounsaturated fatty acids ( MUFAs ) based on evidence on lipid profile alone , the chronic effects of the mentioned replacements on insulin secretion and insulin sensitivity are however unclear . OBJECTIVE To assess the chronic effects of the substitution of refined carbohydrate or MUFA for SAFA on insulin secretion and insulin sensitivity in central ly obese subjects . METHODS Using a crossover design , r and omized controlled trial in abdominally overweight men and women , we compared the effects of substitution of 7 % energy as carbohydrate or MUFA for SAFA for a period of 6 weeks each . Fasting and postpr and ial blood sample s in response to corresponding SAFA , carbohydrate , or MUFA-enriched meal-challenges were collected after 6 weeks on each diet treatment for the assessment of outcomes . RESULTS As expected , postpr and ial nonesterified fatty acid suppression and elevation of C-peptide , insulin and glucose secretion were the greatest with high-carbohydrate ( CARB ) meal . Interestingly , CARB meal attenuated postpr and ial insulin secretion corrected for glucose response ; however , the insulin sensitivity and disposition index were not affected . SAFA and MUFA had similar effects on all markers except for fasting glucose-dependent insulinotropic peptide concentrations , which increased after MUFA but not SAFA when compared with CARB . CONCLUSION In conclusion , a 6-week lower-fat/higher-carbohydrate ( increased by 7 % refined carbohydrate ) diet may have greater adverse effect on insulin secretion corrected for glucose compared with isocaloric higher-fat diets . In contrast , exchanging MUFA for SAFA at 7 % energy had no appreciable adverse impact on insulin secretion Summary Type 2 ( insulin independent ) diabetic women were r and omly allocated to receive advice for low fat diets or low carbohydrate diets . By 24 h weighed dietary intakes before and after a mean interval of six months , patients in the low fat group had reduced their fat intake from 41 % to 31 % of total energy , while carbohydrate percentage of total energy intake increased from 38 % to 46 % . Percentage energy intake from fat and carbohydrate in the control group remained unchanged . Body weight fell in both groups , especially for patients in the low fat group who were obese ( weight/height2 ⩾ 28 kg/m2 ) . Mean plasma glucose , HbA1 , and triglycerides were unchanged . Mean plasma total cholesterol fell significantly in the low fat group compared with the controls ( p < 0.001 ) , but there was no significant difference in the small reduction of high density lipoprotein cholesterol observed in both groups . Thus , adherence to low fat diets occurred without deterioration of diabetes and with benefit for weight and total cholesterol BACKGROUND Few well-controlled studies have comprehensively examined the effects of very-low-carbohydrate diets on  type 2 diabetes ( T2D ) . OBJECTIVE We compared the effects of a very-low-carbohydrate , high-unsaturated fat , low-saturated fat ( LC ) diet with a high-carbohydrate , low-fat ( HC ) diet on glycemic control and cardiovascular disease risk factors in T2D after 52 wk . DESIGN In this r and omized controlled trial that was conducted in an outpatient research clinic , 115 obese adults with T2D [ mean ± SD age : 58 ± 7 y ; body mass index ( in kg/m(2 ) ) : 34.6 ± 4.3 ; glycated hemoglobin ( HbA1c ) : 7.3 ± 1.1 % ; duration of diabetes : 8 ± 6 y ] were r and omly assigned to consume either a hypocaloric LC diet [ 14 % of energy as carbohydrate ( carbohydrate < 50 g/d ) , 28 % of energy as protein , and 58 % of energy as fat ( < 10 % saturated fat ) ] or an energy-matched HC diet [ 53 % of energy as carbohydrate , 17 % of energy as protein , and 30 % of energy as fat ( < 10 % saturated fat ) ] combined with supervised aerobic and resistance exercise ( 60 min ; 3 d/wk ) . Outcomes were glycemic control assessed with use of measurements of HbA1c , fasting blood glucose , glycemic variability assessed with use of 48-h continuous glucose monitoring , diabetes medication , weight , blood pressure , and lipids assessed at baseline , 24 , and 52 wk . RESULTS Both groups achieved similar completion rates ( LC diet : 71 % ; HC diet : 65 % ) and mean ( 95 % CI ) reductions in weight [ LC diet : -9.8 kg ( -11.7 , -7.9 kg ) ; HC diet : -10.1 kg ( -12.0 , -8.2 kg ) ] , blood pressure [ LC diet : -7.1 ( -10.6 , -3.7)/-6.2 ( -8.2 , -4.1 ) mm Hg ; HC diet : -5.8 ( -9.4 , -2.2)/-6.4 ( -8.4 , -4.3 ) mm Hg ] , HbA1c [ LC diet : -1.0 % ( -1.2 % , -0.7 % ) ; HC diet : -1.0 % ( -1.3 % , -0.8 % ) ] , fasting glucose [ LC diet : -0.7 mmol/L ( -1.3 , -0.1 mmol/L ) ; HC diet : -1.5 mmol/L ( -2.1 , -0.8 mmol/L ) ] , and LDL cholesterol [ LC diet : -0.1 mmol/L ( -0.3 , 0.1 mmol/L ) ; HC diet : -0.2 mmol/L ( -0.4 , 0.03 mmol/L ) ] ( P-diet effect ≥ 0.10 ) . Compared with the HC-diet group , the LC-diet group achieved greater mean ( 95 % CI ) reductions in the diabetes medication score [ LC diet : -0.5 arbitrary units ( -0.7 , -0.4 arbitrary units ) ; HC diet : -0.2 arbitrary units ( -0.4 , -0.06 arbitrary units ) ; P = 0.02 ] , glycemic variability assessed by measuring the continuous overall net glycemic action-1 [ LC diet : -0.5 mmol/L ( -0.6 , -0.3 mmol/L ) ; HC diet : -0.05 mmol/L ( -0.2 , -0.1 mmol/L ) ; P = 0.003 ] , and triglycerides [ LC diet : -0.4 mmol/L ( -0.5 , -0.2 mmol/L ) ; HC diet : -0.01 mmol/L ( -0.2 , 0.2 mmol/L ) ; P = 0.001 ] and greater mean ( 95 % CI ) increases in HDL cholesterol [ LC diet : 0.1 mmol/L ( 0.1 , 0.2 mmol/L ) ; HC diet : 0.06 mmol/L ( -0.01 , 0.1 mmol/L ) ; P = 0.002 ] . CONCLUSIONS Both diets achieved substantial weight loss and reduced HbA1c and fasting glucose . The LC diet , which was high in unsaturated fat and low in saturated fat , achieved greater improvements in the lipid profile , blood glucose stability , and reductions in diabetes medication requirements , suggesting an effective strategy for the optimization of T2D management . This trial was registered at www.anzctr.org.au as ACTRN12612000369820 We compared a high-carbohydrate diet with a high-fat diet ( specifically , a diet high in monounsaturated fatty acids ) for effects on glycemic control and plasma lipoproteins in 10 patients with non-insulin-dependent diabetes mellitus ( NIDDM ) receiving insulin therapy . The patients were r and omly assigned to receive first one diet and then the other , each for 28 days , in a metabolic ward . In the high-carbohydrate diet , 25 percent of the energy was in the form of fat and 60 percent in the form of carbohydrates ( 47 percent of the total energy was in the form of complex carbohydrates ) ; the high-monounsaturated-fat diet was 50 percent fat ( 33 percent of the total energy in the form of monounsaturated fatty acids ) and 35 percent carbohydrates . The two diets had the same amounts of simple carbohydrates and fiber . As compared with the high-carbohydrate diet , the high-monounsaturated-fat diet result ed in lower mean plasma glucose levels and reduced insulin requirements , lower levels of plasma triglycerides and very-low-density lipoprotein cholesterol ( lower by 25 and 35 percent , respectively ; P less than 0.01 ) , and higher levels of high-density lipoprotein ( HDL ) cholesterol ( higher by 13 percent ; P less than 0.005 ) . Levels of total cholesterol and low-density lipoprotein ( LDL ) cholesterol did not differ significantly in patients on the two diets . These preliminary results suggest that partial replacement of complex carbohydrates with monounsaturated fatty acids in the diets of patients with NIDDM does not increase the level of LDL cholesterol and may improve glycemic control and the levels of plasma triglycerides and HDL cholesterol Approximately 80 % of patients with type 2 diabetes are overweight/obese ( 1 ) , and weight loss is the mainstay of treatment for these individuals . However , there is growing controversy as to whether reduced-fat or reduced-carbohydrate diets are best suited for this purpose , and results ( 2–8 ) in nondiabetic subjects suggest that lower carbohydrate diets are similarly or more efficacious in improving weight , triglycerides , and HDL cholesterol . There are no published r and omized studies evaluating the role of dietary macronutrients with respect to weight loss and cardiovascular risk improvement in patients with type 2 diabetes . Thus , we r and omized diet-treated patients with type 2 diabetes to hypocaloric diets , moderately restricted in either carbohydrate or fat , to determine whether weight loss or metabolic improvement differed as a function of macronutrient composition . A total of 29 patients with diet-treated type 2 diabetes were recruited from the San Francisco Bay area . All subjects gave written informed consent . Inclusion criteria included BMI 27–36 kg/m2 , fasting plasma glucose concentration 7.2–8.3 mmol/l , no use of antihyperglycemic medications , and stable weight for 3 months . Subjects on anti-hypertensive or cholesterol-lowering drugs or aspirin were allowed to continue their medications . Insulin-mediated glucose uptake was quantified by a modification ( 9 ) of the insulin suppression test as originally described ( 10 ) and vali date d ( 11 ) . In this test , a 180-min infusion of somatostatin ( 0.27 μg/m2 per min ) , insulin ( 25 mU/m2 per min ) ,
In contrast , fasting plasma glucose , fasting plasma insulin as well as the homeostasis model assessment of insulin resistance were not affected by the amounts of MUFA in the dietary protocol s. Conclusions : In summary , this systematic review found that high MUFA diets appear to be effective in reducing HbA1c , and therefore , should be recommended in the dietary regimes of T2D
Background / Aims : In 2008 , the American Diabetes Association recommended low-carbohydrate or low-fat diets for weight management in patients with established type 2 diabetes ( T2D ) , while the amount of monounsaturated fatty acids ( MUFA ) was not specified .
This systematic review focused on the effects of diets high in MUFA versus diets low in MUFA on important risk factors of T2D ( i.e. plasma glucose , insulin , homeostasis model assessment of insulin resistance and glycosylated haemoglobin , HbA1c ) .