***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The influence of the source of dietary fat on postpr and ial thermogenesis and substrate oxidation rates , was examined in twelve postmenopausal women aged 57 - 73 years , with BMI 21.9 - 38.3 kg/m(2 ) . A single blind , r and omised , paired comparison of two high-fat , isoenergetic , mixed test meals was conducted . The major source of fat was either cream ( CREAM ) or extra virgin olive oil ( EVOO ) .  RMR , diet-induced thermogenesis ( DIT ) and substrate oxidation rates over 5 h were measured by indirect calorimetry . There were no differences in body weight , RMR , fasting carbohydrate or fat oxidation rates between the two occasions . DIT ( EVOO 97 ( SD 46 ) v. CREAM 76 ( SD 69 ) kJ/5 h and EVOO 5.2 ( SD 2.5 ) v. CREAM 4.1 ( SD 3.7)% energy ) did not differ between the two test meals . The postpr and ial increase in carbohydrate oxidation rates , relative to their respective fasting values ( DeltaCOX ) , was significantly lower following the EVOO meal ( EVOO 10.6 ( SD 8.3 ) v. CREAM 17.5 ( SD 10 ) g/5 h ; paired t test , P=0.023 ) , while postpr and ial fat oxidation rates ( DeltaFOX ) were significantly higher ( EVOO 0.0 ( SD 4.4 ) v. CREAM -3.6 ( sd 4.0 ) g/5 h ; P=0.028 ) . In the eight obese subjects , however , DIT was significantly higher following the EVOO meal ( EVOO 5.1 ( SD 2.0 ) v. CREAM 2.5 ( sd 2.9 ) % ; P=0.01 ) . This was accompanied by a significantly lower DeltaCOX ( EVOO 10.9 ( SD 9.9 ) v. CREAM 17.3 ( SD 10.5 ) g/5 h ; P=0.03 ) and significantly higher DeltaFOX ( EVOO 0.11 ( SD 4.4 ) v. CREAM -4.1 ( SD 4.5 ) g/5 h , P=0.034 ) . The present study showed that olive oil significantly promoted postpr and ial fat oxidation and stimulated DIT in abdominally obese postmenopausal women The aim of this dynamic prospect i ve follow-up study was to assess the association between olive oil consumption and the likelihood of weight gain or the incidence of overweight or obesity in a large Mediterranean cohort of 7,368 male and female Spanish university graduates ( the SUN Project ) who were followed for a median period of 28.5 mon . A vali date d Food Frequency Question naire was administered at baseline , and respondents also completed a follow-up question naire after 28.5 mon . Changes in participants ' consumption of olive oil and their weight were assessed during follow-up . A higher baseline consumption of olive oil was associated with a lower likelihood of weight gain , although the differences were not statistically significant . The adjusted difference in weight gain ( kg ) was −0.16 [ 95 % confidence interval ( C1 ) : −0.42 to + 0.11 ] for participants in the upper quintile of olive oil consumption ( median : 46 g/d ) compared with those in the lowest quintile ( median : 6 g/d ) . For participants with a high baseline consumption of olive oil  whose olive oil consumption also increased during follow-up , we found a slightly increased but nonsignificant risk of incidence of over-weight or obesity ( adjusted odds ratio=1.19 , 95 % C1 : 0.73 to 1.95 ) . Our study , carried out in a sample of free-living people , shows that a high amount of olive oil consumption is not associated with higher weight gain or a significantly higher risk of developing overweight or obesity in the context of the Mediterranean food pattern 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 Adherence to a Mediterranean diet has been reported to increase longevity , but concerns have been expressed that such a diet may promote overweight and obesity . OBJECTIVE The objective was to investigate whether adherence to the traditional Mediterranean diet , as operationalized in a Mediterranean diet score , is associated with body mass index ( BMI ) and waist-to-hip ratio ( WHR ) . DESIGN In a general population sample of 23,597 adult men and women participating in the Greek European Prospect i ve Investigation into Cancer and Nutrition Study , a vali date d food-frequency question naire was interviewer-administered , and anthropometric , sociodemographic , physical activity , and other lifestyle characteristics were recorded . BMI and WHR were regressed on a score that reflects adherence to the traditional Mediterranean diet and potentially confounding variables . RESULTS In models in which total energy intake was included , adherence to the Mediterranean diet was unrelated to BMI in both sexes and was weakly related to WHR only in women . When energy intake was not controlled for , a 2-point increase in the score was found to correspond to increases of approximately 650 and 150 g in the weight of an average-height man and woman , respectively , whereas the WHR was found to increase by approximately 0.001 units in men and 0.004 units in women . CONCLUSIONS Adherence to a Mediterranean diet was essentially unrelated to BMI , with small differences depending on model choice and having no practical consequences . Overweight is a genuine problem in Greece and perhaps other Mediterranean countries , but it is likely to be related to limited physical activity in conjunction with excessive positive energy balance Few studies have prospect ively examined dietary patterns and adult weight change , and results to date are inconsistent . This study examines whether a Mediterranean diet ( MD ) pattern is associated with reduced 3-y incidence of obesity using data from the Spanish cohort of the European Prospect i ve Investigation into Cancer and Nutrition ( EPIC-Spain ) . The sample included 17,238 women and 10,589 men not obese and aged 29 - 65 y at baseline ( 1992 - 96 ) . Height and weight were measured at baseline ; weight was self-reported in a follow-up survey a mean of 3.3 y later . Detailed dietary history data , collected using a vali date d method , were used to construct a MD score .  Logistic regression models were used to estimate odds of becoming overweight or obese . Among initially overweight subjects , 7.9 % of women and 6.9 % of men became obese , whereas 13.8 % of normal weight men and 23.0 % women became overweight . High  MD adherence  was associated with significantly lower likelihood of becoming obese among overweight subjects , with stronger associations after adjusting for underreporting of dietary data . Associations ( odds ratios with 95 % CI ) were similar in women ( 0.69 , 0.54 - 0.89 ) and men ( 0.68 , 0.53 - 0.89 ) . Adjusting for the plausibility of reported dietary intakes increased the magnitude of these associations , which were approximately 0.8 without this adjustment .  MD adherence was not associated with incidence of overweight in initially normal-weight subjects . Nonetheless , results suggest that promoting eating habits consistent with MD patterns may be a useful part of efforts to combat obesity A r and omised crossover study of eight overweight or obese men ( aged 24 - 49 years , BMI 25.5 - 31.3 kg/m(2 ) ) , who followed two diets for 4 weeks each , was performed to determine whether substitution of saturated fat with monounsaturated fat affects body weight and composition . Subjects were provided with all food and beverages as modules ( selected ad libitum ) of constant macronutrient composition , but differing energy content . The % total energy from saturated fat , monounsaturated fat and polyunsaturated fat was 24 , 13 and 3 % respectively on the saturated fatty acid (SFA)-rich diet and 11 , 22 and 7 % respectively on the monounsaturated fatty acid (MUFA)-rich diet . MUFA accounted for about 80 % of the unsaturated fats consumed on both diets . Body composition , blood pressure , energy expenditure ( resting and postpr and ial metabolic rates , substrate oxidation rate , physical activity ) , serum lipids , the fatty acid profile of serum cholesteryl esters and plasma glucose and insulin concentrations were measured before and after each diet period . Significant ( P < or = 0.05 ) differences in total cholesterol and the fatty acid composition of serum cholesteryl esters provided evidence of dietary adherence . The men had a lower weight ( -2.1 ( SE 0.4 ) kg , P=0.0015 ) and fat mass ( -2.6 ( SE 0.6 ) kg , P=0.0034 ) at the end of the MUFA-rich diet as compared with values at the end of the SFA-rich diet . No significant differences were detected in energy or fat intake , energy expenditure , substrate oxidation rates or self-reported physical activity . Substituting dietary saturated with unsaturated fat , predominantly MUFA , can induce a small but significant loss of body weight and fat mass without a significant change in total energy or fat intake Context Some experts attribute a low incidence of heart disease in Mediterranean countries to dietary habits . Contribution In this multicenter , 3-group trial , investigators r and omly assigned 772 adults at high risk for cardiovascular disease to a low-fat diet or to a Mediterranean diet supplemented with either virgin olive oil ( 1 L per week ) or nuts ( 30 g per day ) . After 3 months , the Mediterranean diet groups had lower mean plasma glucose level , systolic blood pressure , and total cholesterolhigh-density lipoprotein cholesterol ratio than the low-fat diet group . Caution s The Mediterranean diet groups received more nutritional education than the low-fat diet group . Implication s Mediterranean diets supplemented with olive oil or nuts may improve cardiovascular risk factors . The Editors Cardiovascular disease is the main cause of death in industrialized countries , but incidence rates have marked geographic differences . The low incidence of coronary heart disease ( CHD ) in Mediterranean countries has been partly ascribed to dietary habits ( 1 - 3 ) . Recent findings from large European cohort studies ( 4 - 6 ) suggest that a high degree of adherence to the Mediterranean diet is associated with a reduction in mortality . In small clinical studies , the Mediterranean diet or some of its components have reduced blood pressure ( 7 ) and have improved lipid profiles ( 8 , 9 ) and endothelial function ( 10 ) . Moreover , a recent cross-sectional study ( 11 ) and a 2-year feeding trial ( 12 ) have shown 
    Output:
    
Although the results are inconsistent , the evidence points towards a possible role of the Mediterranean diet in preventing overweight/obesity , and physiological mechanisms can explain this protective effect .