Anthropometric, metabolic and dietary fatty acids profiles in lean and obese diabetic Asian Indian subjects

The present study was aimed to study anthropometric, metabolic and dietary fatty acids profiles among 200 (Group I: lean control, N = 80; Group II: lean diabetic, N = 70 and Group III: obese diabetic, N = 50) Asian Indians (aged 30 years and above) living in the eastern part of India. Anthropometric [height, weight, waist (WC) and hip circumference] metabolic [total cholesterol (TC), triglyceride (TG), high (HDL), low density lipoprotein (LDL) and fasting plasma glucose (FPG)] and dietary profiles were collected from each participant. Body mass index (BMI), waist-hip ratio (WHR) and conicity index (CI) were subsequently computed from anthropometric measures. An open-ended 24 h food recall proforma consisting of three sections and in local language was used to collect nutrient information from each participant. Daily intake of nutrients including saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) were estimated by adding all the foodstuffs consumed on weekly and monthly basis. One-way ANOVA with Scheffe's post-hoc test revealed that Group I has significantly lower mean than both Group II and Group III for age, WC, WHR, CI, TC, TG, LDL, FPG and total carbohydrates; Group I has significantly lower mean than Group II only for HDL and Group I has significantly lower mean than Group III only for BMI, total proteins and total fats. On the other hand, Group I has significantly greater mean than both Group II and Group III for UFA/SFA, MUFA/SFA and PUFA/SFA whereas Group I has significantly lower mean than Group III only for trans fatty acids and Erucic acid. Pearson's partial correlation (controlling age and sex) analysis showed that the ratios of unsaturated fatty acids and saturated fatty acids had significant negative association with lipids, lipoprotein and fasting glucose. Discriminant analysis revealed that overall 86.2% of all cases were correctly (positively) classified in three groups using fatty acids and their ratios. In conclusion, it seems reasonable to argue that dietary management including dietary guidelines would be useful to retard the growing incidence of diabetes in Indian population.     

Relation between plasma leptin and anthropometric and metabolic covariates in lean and obese diabetic and hyperlipidaemic Asian Northern Indian subjects

This study investigated the relationship of plasma leptin to obesity, diabetes and hyperlipidaemia in Asian Northern Indian subjects, considered to have a predisposition to abdominal obesity and metabolic syndrome. A total of 72 subjects, subcategorised into lean and obese healthy subjects, lean and obese Type 2 diabetic and lean and obese non-diabetic hyperlipidaemic subjects were recruited. High leptin values were observed in all obese groups, and obese diabetic patients showed the highest levels. In lean and obese diabetic subjects, plasma leptin did not show any correlation to any index of glycaemia. When all lean and all obese subjects were analysed in two separate groups, body mass index (BMI), percent total body fat, and body density significantly correlated with the plasma leptin levels (p<0.05). Leptin values, when correlated to all variables in all patients taken together, showed the greatest magnitude of correlation with BMI (r=0.64), percent total body fat (r=0.67), and waist circumference (r=0.51). Strong inverse correlation was seen with body density (r=-0.67). Levels of serum insulin did not show any correlation with leptin levels in all subjects combined, and separately in various groups. Multiple linear regression analysis performed in obese, non-diabetic and normolipidaemic subjects, all Type 2 diabetic and all non-diabetic hyperlipidaemic subjects separately showed that percent total body fat is the only significant predictor of plasma leptin concentration in all the 3 groups. The present study suggests that plasma leptin has a strong positive correlation with percent total body fat in Asian Northern Indian subjects. Among other components of metabolic syndrome, only abdominal obesity is weakly correlated to serum leptin levels.     

Effect of dietary fatty acids on the postprandial fatty acid composition of triacylglycerol-rich lipoproteins in healthy male subjects

OBJECTIVE: The aim of the present study was to investigate the effect of trans-18:1 isomers compared to other fatty acids, especially saturates, on the postprandial fatty acid composition of triacylglycerols (TAG) in chylomicrons and VLDL. DESIGN: A randomised crossover experiment where five interesterified test fats with equal amounts of palmitic acid (P fat), stearic acid (S fat), trans-18:1 isomers (T fat), oleic acid (O fat), or linoleic acid (L fat) were tested. SUBJECTS: A total of 16 healthy, normolipidaemic males (age 23+/-2 y) were recruited. INTERVENTIONS: The participants ingested fat-rich test meals (1 g fat per kg body weight) and the fatty acid profiles of chylomicron and VLDL TAG were followed for 8 h. RESULTS: The postprandial fatty acid composition of chylomicron TAG resembled that of the ingested fats. The fatty acids in chylomicron TAG were randomly distributed among the three positions in accordance with the distributions in test fats. Calculations of postprandial TAG concentrations from fatty acid data revealed increasing amounts up to 4 h but lower response curves (IAUC) for the two saturated fats in accordance with previous published data. The T fat gave results comparable to the O and L fats. The test fatty acids were much less reflected in VLDL TAG and there was no dietary influence on the response curves. CONCLUSIONS: The fatty acid composition in the test fats as well as the positional distributions of these were maintained in the chylomicrons. No specific clearing of chylomicron TAG was observed in relation to time.     

Tracing the fate of dietary fatty acids: metabolic studies of postprandial lipaemia in human subjects

Most postprandial studies have investigated the response of a single meal, yet the ingestion of sequential meals is more typical in a Western society. The aim of this review is to explain how natural and stable isotope tracers of fatty acids have been used to investigate the metabolism of dietary fat after single and multiple meals, with a focus on in vivo measurements of adipose tissue metabolism. When stable isotope tracers are combined with arteriovenous difference measurements, very specific measurements of metabolic flux across tissues can be made. We have found that adipose tissue is a net importer of dietary fat for 5 h following a single test meal and for most of the day during a typical three-meal eating pattern. When dietary fat is cleared from plasma, some fatty acids 'spillover' into the plasma and contribute up to 50% of postprandial plasma NEFA concentrations. Therefore, plasma NEFA concentrations after a meal reflect the balance between intracellular and extracellular lipolysis in adipose tissue. This balance is altered after the acute ingestion of fructose. The enzyme lipoprotein lipase is a key modulator of fatty acid flux in adipose tissue and its rate of action is severely diminished in obese men. In conclusion, in vivo studies of human metabolism can quantify the way that adipose tissue fatty acid trafficking modulates plasma lipid concentrations. This has implications for the flux of fatty acids to tissues that are susceptible to ectopic fat deposition such as the liver and muscle.     

The relationships between anthropometric measurements,serum vitamin A and E concentrations and lipid profiles in overweight and obese subjects

The weight, height, body mass index (BMI), waist/hip ratio, serum retinol and alpha-tocopherol and lipid profiles of 16 overweight (BMI > or = 25.0 kg/m2) Thai males and 56 overweight females, compared with 14 males and 58 females in a control group (BMI 18.5-24.9 kg/m2), were investigated. Subjects for the study were those persons who turned up regularly for physical check-up at the Outpatient Department, General Practice Section of Rajvithi Hospital, Bangkok. The study was conducted between December 2000-March 2001. Higher levels of cholesterol, LDL-C, LDL-C/HDL-C ratio were found in the overweight compared with the control subjects. Statistically significant higher triglyceride levels were found in the overweight compared with the control subjects. The median serum retinol concentration in overweight subjects was 2.80 mumol/L (range 0.53-4.62 mumol/L) compared with 2.97 mumol/L (range 1.21-4.12 mumol/L) in control subjects (p = 0.0736). The median serum alpha-tocopherol concentration in overweight subjects was 17.30 mumol/L (range 6.29-28.65 mumol/L) compared with 18.75 mumol/L (range 5.30-30.28 mumol/L) in control subjects (P < 0.05). The median values of retinol and alpha-tocopherol serum concentrations in the overweight and obese males were lower than those of the overweight and obese females. A total of 6.3% (1 out of 16) and 12.5% (2 out of 16) of the overweight/obese males had decreased retinol and alpha-tocopherol levels, while the overweight/obese females had decreased retinol and alpha-tocopherol level of 1.8% (1 out of 56) and 10.7% (6 out of 56), respectively. A total of 12.5% and 39.3% of the overweight/obese males and females had cholesterol concentrations of > or = 6.48 mmol/l. However, the prevalence of low HDL-C (HDL-C < or = 0.91 mmol/l) was found to be 50% in the overweight and obese males and 10.7% in the overweight and obese females. Statistically significant associations were found between age, cholesterol, LDL-C, and serum alpha-tocopherol in the overweight and obese male and female subjects. A negative correlation was found between weight, BMI, AC, MAMC, hip circumference and serum retinol in both the overweight and obese subjects. A negative correlation was found between weight, BMI, MAMC, waist, hip circumferences and serum alpha-tocopherol in both the overweight and obese subjects.     

Responses of lean and obese subjects to preloads, deprivation, and palatability

The effects of preloads, deprivation, and palatability on the eating behavior of non-dieting lean and obese subjects were studied during laboratory meals, using small solid food units (SFUs) to measure the rate of ingestion over the time-course of the meals. In both weight groups, rate of intake decreased from the beginning to the end of meals. The smaller the preloads and the longer the deprivation interval, the faster subjects ate at the beginning of meals and the higher their hunger ratings were. The longest deprivation interval also increased palatability ratings, meal length, and the total amount that subjects ate. Increasing the palatability of the food increased the rate of intake at the beginning of meals, meal length, and the amount of food that subjects ate. Obese subjects were more sensitive to palatability and less responsive to deprivation than lean subjects. For example, while lean subjects became less discriminating about the palatability of the food at the beginning of meals as deprivation increased, obese subjects did not. The satiation mechanism of obese subjects was also different from lean subjects. For example, obese subjects overate after preloads while lean subjects underate compared to their baselines.     

Plasma adiponectin increases postprandially in obese,but not in lean,subjects

OBJECTIVE: We investigated the acute responses of plasma adiponectin levels to a test meal in lean and obese subjects. RESEARCH METHODS AND PROCEDURES: We studied 13 lean and 11 obese subjects after a 10-hour overnight fast. Glucose, insulin, and adiponectin concentrations were measured at baseline and 15, 30, 60, 120, and 180 minutes after a fixed breakfast. RESULTS: At baseline, fasting adiponectin concentrations were lower in the obese group vs. the lean group [mean (95% confidence interval): 2.9 (2.1 to 4.1) microg/mL vs. 8.6 (6.5 to 11.3) microg/mL], but rose 4-fold postprandially in the obese group, reaching a peak at 60 minutes [baseline: 2.9 (2.1 to 4.1) microg/mL vs. 60 minutes: 12.1 (8.5 to 17.4) microg/mL; p< 0.0001] and remaining elevated for the remainder of the study. There were no postprandial changes in plasma adiponectin concentrations in lean subjects. DISCUSSION: This increase of adiponectin concentrations in obese individuals might have important beneficial effects on postprandial glucose and lipid metabolism and might be viewed as a mechanism for maintaining normal glucose tolerance in those who are obese and insulin resistant.     

Effects of dietary saturated, monounsaturated, and n-3 fatty acids on blood pressure in healthy subjects

BACKGROUND: The quantity and quality of fats consumed in the diet influence the risk of cardiovascular disease (CVD). Although the effect of diet on plasma lipids and lipoproteins is well documented, less information exists on the role of fats on blood pressure (BP). OBJECTIVE: The objective was to evaluate the effects of different types of dietary fat on BP in healthy subjects. DESIGN: Healthy subjects (n = 162) were randomly assigned for 3 mo to follow 1 of 2 isoenergetic diets: 1 rich in monounsaturated fatty acids (MUFA diet) and the other rich in saturated fatty acids (SFA diet). Each group was further randomly assigned to receive supplementation with fish oil (3.6 g n-3 fatty acids/d) or placebo. RESULTS: Systolic BP (SBP) and diastolic BP (DBP) decreased with the MUFA diet [-2.2% (P = 0.009) and -3.8% (P = 0.0001), respectively] but did not change with the SFA diet [-1.0% (P = 0.2084) and -1.1% (P = 0.2116)]. The MUFA diet caused a significantly lower DBP than did the SFA diet (P = 0.0475). Interestingly, the favorable effects of MUFA on DBP disappeared at a total fat intake above the median (>37% of energy). The addition of n-3 fatty acids influenced neither SBP nor DBP. CONCLUSIONS: Changing the proportions of dietary fat by decreasing SFAs and increasing MUFAs decreased diastolic BP. Interestingly, the beneficial effect on BP induced by fat quality was negated by the consumption of a high total fat intake. The addition of n-3 fatty acids to the diet had no significant effect on BP.     

Effects of dietary trans fatty acids on blood pressure in normotensive subjects.

Consumption of essential fatty acids of the (n-6) series may affect blood pressure in man. Trans fatty acids in the diet interfere with the metabolism of essential fatty acids in rats. We therefore measured the effect of dietary trans fatty acids on blood pressure in 25 men and 34 women. Each subject consumed, in random order, three mixed natural diets, each for three weeks. The composition of the three diets was similar, except for 10.4 per cent of energy, which was provided by either oleic acid, trans fatty acids, or saturated fatty acids. The intake from polyunsaturated fatty acids was 3.4 per cent on the saturated-fat diet and 4.6 per cent on the other two diets. On the oleic-acid diet systolic blood pressure was 113 +/- 12.8 mmHg and diastolic blood pressure 66 +/- 8.3 mmHg, on the trans-fatty-acid diet 112 +/- 12.2 mmHg and 67 +/- 8.1 mmHg, and on the saturated-fat diet 112 +/- 12.6 mmHg and 67 +/- 8.1 mmHg. No significant differences were observed in blood pressure levels between the three diets. We conclude that neither trans nor saturated fatty acids influence blood pressure levels in normotensive subjects relative to oleic acid.     

The long-term influence of orlistat on dietary intake in obese subjects with components of metabolic syndrome

Background:  Orlistat is a lipase inhibitor that reduces the intestinal absorption of fat and may enhance the effects of dietary and behavioural therapy on weight loss and maintenance. The present study examined the effect of orlistat on dietary intake, especially fat intake, during long-term weight maintenance.
Methods:  Subjects comprised 44 men and women (aged 18–63 years; body mass index 37.5 ± 4.3 kg m⁻²) included in the Scandinavian Multicenter study of Obese subjects with the metabolic syndrome, a 3-year clinical trial of orlistat or placebo following an 8-week, very low energy diet (VLED). Two months after the end of the trial when the use of orlistat was optional, 33 subjects remained in the study. A dietary interview based on a validated food frequency questionnaire was conducted before the VLED, after 1 year of treatment with orlistat or placebo and 2 months after the end of the trial.
Results:  At 1 year, dietary intake did not differ between the orlistat and placebo group. Energy percent (E%) fat was reduced and E% carbohydrate was increased within both groups. Two months after the end of the trial, E% fat was 32.6% (SD 6.2%) in subjects that chose to take orlistat and 27.7% (SD 5.5%) in subjects not taking orlistat [between group difference −5.0% (95% confidence interval −9.2 to −0.7); P  = 0.021].
Conclusions:  The use of orlistat compared with placebo in a lifestyle modification programme does not appear to influence dietary intake. Subjects that chose to take orlistat after the end of the programme did not comply with dietary recommendations and this may hamper the effect of the drug.     

Habitual dietary intake and insulin sensitivity in lean and obese adults.

Studies in rodents have shown that short-term increases in dietary fat result in fat cell enlargement and insulin resistance. In humans, although high-fat diets have been associated with obesity, little is known about the specific metabolic effects of these diets. In this study we explored possible associations between habitual dietary composition and insulin sensitivity. Twenty-two lean and 23 obese subjects were characterized by dietary history (food frequency questionnaire), anthropometrics, oral glucose tolerance, and insulin sensitivity (SI, from the minimal model). As shown previously, body mass index was positively correlated with percent of energy intake as fat (r = 0.47, P = 0.001). Increasing fat intake was also associated with diminished SI (r = -0.41, P = 0.01). In contrast, SI was positively correlated with fiber intake (r = 0.43, P = 0.007). Multivariate analysis confirmed the importance of dietary fiber for SI. We conclude that habitually low dietary fiber intake, along with elevated dietary fat, correlates with diminished SI in otherwise healthy lean and obese subjects.     

Gastric distention by balloon and test-meal intake in obese and lean subjects

A study was conducted to determine the effects of various levels of gastric distension on spontaneous meal intake. A balloon was inserted into the stomach of four lean and four obese subjects before consumption of a lunch meal. On different days the balloon was filled with 0, 200, 400, 600, and 800 mL water in a random sequence. As balloon volume increased, food intake decreased, with a balloon volume of greater than or equal to 400 mL significantly reducing intake (p less than 0.01). There was no significant difference between lean and obese subjects. Because gastric emptying rate was not significantly slowed by a volume of 800 mL, between emptying was probably not a factor in inducing satiety. Discomfort was probably also not a factor because it was experienced by only two lean subjects at 800 mL. Most likely gastric distension itself triggered satiety signals.     

Differences in short-term metabolic responses to a lipid load in lean (resistant) vs obese (susceptible) young male subjects with habitual high-fat consumption

OBJECTIVE: To determine the role of macronutrients oxidation ability in the postprandial response to a high lipid load in the mechanisms conferring resistance or susceptibility to obesity. SUBJECTS AND DESIGN: Nine lean and nine obese young male subjects with habitual similar high-fat intake (>40 % of energy) and comparable physical activity were selected and categorized as 'resistant', those who remained lean (body mass index (BMI) <25 kg/m2), and 'susceptible', those who were obese (BMI>30 kg/m2). Fasting blood samples were taken for the evaluation of blood metabolic and hormonal variables. Resting metabolic rate (RMR) and substrates oxidation were measured by indirect calorimetry, in the fasting state and every 30 min for 3 h after a rich lipid meal (fat 94.7%) supplied to cover the 50% of the volunteers energy requirements. The study was performed at the Metabolic Unit of the University of Navarra. RESULTS: Fasting RMR and lipid oxidation were higher in obese-susceptible subjects. However, similar values were found in both groups after adjustment for fat mass and free fat mass. The cumulative postprandial fat oxidation was also similar in both groups (despite having different tissue metabolic activity), whereas cumulative carbohydrate oxidation was lower in the obese-susceptible group. The thermic effect of food (% of dietary induced thermogenesis) was lower (P<0.05) in the susceptible-obese subjects. The energy and fat balance were more positive in the obesity-susceptible individuals after the high fat load, who also showed higher fasting homeostatic model assessment index, low-density lipoprotein-cholesterol and triacylglyceride levels, hyperleptinemia and hypoadiponectinemia. CONCLUSION: Lean-resistant individuals came closer to achieving fat balance than obese-susceptible subjects. These metabolic and hormonal differences are probably genetically determined.     

Beneficial metabolic effects of regular meal frequency on dietary thermogenesis, insulin sensitivity, and fasting lipid profiles in healthy obese women

BACKGROUND: Although a regular meal pattern is recommended for obese people, its effects on energy metabolism have not been examined. OBJECTIVE: We investigated whether a regular meal frequency affects energy intake (EI), energy expenditure, or circulating insulin, glucose, and lipid concentrations in healthy obese women. DESIGN: Ten women [x +/- SD body mass index (in kg/m(2)): 37.1 +/- 4.8] participated in a randomized crossover trial. In phase 1 (14 d), the subjects consumed their normal diet on 6 occasions/d (regular meal pattern) or followed a variable meal frequency (3-9 meals/d, irregular meal pattern). In phase 2 (14 d), the subjects followed the alternative pattern. At the start and end of each phase, a test meal was fed, and blood glucose, lipid, and insulin concentrations were determined before and for 3 h after (glucose and insulin only) the test meal. Subjects recorded their food intake on 3 d during each phase. The thermogenic response to the test meal was ascertained by indirect calorimetry. RESULTS: Regular eating was associated with lower EI (P < 0.01), greater postprandial thermogenesis (P < 0.01), and lower fasting total (4.16 compared with 4.30 mmol/L; P < 0.01) and LDL (2.46 compared with 2.60 mmol/L; P < 0.02) cholesterol. Fasting glucose and insulin values were not affected by meal pattern, but peak insulin concentrations and area under the curve of insulin responses to the test meal were lower after the regular than after the irregular meal pattern (P < 0.01 and 0.02, respectively). CONCLUSION: Regular eating has beneficial effects on fasting lipid and postprandial insulin profiles and thermogenesis.     

人体测量指标预测肥胖儿童非酒精性脂肪肝的研究

目的研究人体测量指标对儿童肥胖伴非酒精性脂肪肝的预测作用,探讨不同指标筛查非酒精性脂肪肝的切点值。方法选取自2018年6月—2019年12月在西安交通大学第二附属医院小儿内分泌门诊就诊的94例肥胖儿童为研究对象,进一步分为肥胖伴非酒精性脂肪肝组与肥胖不伴非酒精性脂肪肝组,52例正常儿童为对照组。测量身高(H)、体重(W)、腰围(WC)、臀围(HC)和血甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C);行肝脏B超的检查。计算体质指数(BMI)、腰臀比(WHR)、腰高比(WHtR)、腹部体积指数(AVI)、脂质蓄积指数(LAP)和内脏脂肪指数(VAI)等指标。通过绘制人体测量指标的受试者工作特征曲线(ROC曲线)评估人体测量指标与肥胖儿童非酒精性脂肪肝的相关性,并比较各项人体测量指标的曲线下面积(AUC)确定切点值。结果肥胖组BMI、WC、WHR、WHtR、AVI、LAP、VAI及TG均高于对照组(t=23.090、21.068、12.547、22.855、17.578、8.159、5.394、6.183,P<0.001)。肥胖伴非酒精性脂肪肝组BMI、WC、AVI、LAP、VAI均高于肥胖不伴非酒精性脂肪肝组(t=2.180、2.389、2.362、3.643、2.839,P<0.05)。人体测量指标的ROC曲线下面积按从大到小的顺序依次为LAP、VAI、WC、AVI、BMI。对肥胖伴非酒精性脂肪肝的联合诊断指标进行筛查效能分析结果显示,LAP+AVI曲线下面积为0.706(95%CI:0.595~0.817,P<0.001);AVI+VAI曲线下面积为0.685(95%CI:0.570~0.800,P<0.01);BMI+WC曲线下面积为0.652(95%CI:0.537~0.768,P<0.05)。联合指标的ROC曲线下面积从大到小为LAP+AVI、AVI+VAI、BMI+WC。结论LAP联合AVI对儿童肥胖伴非酒精性脂肪肝具有较好的筛查作用。     

A comparison of the effects of beef, chicken and fish protein on satiety and amino acid profiles in lean male subjects.

We compared postprandial satiety and plasma amino acid, insulin, and glucose concentrations in six lean male subjects after the ingestion of three types of protein (beef, chicken and fish). Satiety was greater after the fish meal (P less than 0.01). The observed difference in satiety could be correlated with two of the putative satiety signals measured in this study: 1) serotoninergic activity, due to differences observed in the postprandial tryptophan to large neutral amino acid ratio; and 2) digestibility, reflected in the significantly (P less than 0.05) longer time it took for the plasma amino acid concentrations to peak after the fish meal. Correlations between dietary and plasma amino acid concentrations were determined and good correlations (r = 0.90) were observed for essential amino acids other than lysine and tryptophan. There were no differences in insulin or glucose concentrations in subjects after consuming each of the three meals. Whether other differences that we observed, such as increased concentrations of taurine and methionine following the fish meal, had any effect on satiety or were of biological significance is not known.     

Thermic effect of feeding carbohydrate, fat, protein and mixed meal in lean and obese subjects

The thermic effect of 1.67 MJ (400 kcal) of carbohydrate (glucose), fat, protein and mixed meal were examined in 11 lean and 11 obese subjects by indirect calorimetry. The changes in metabolic rate in response over 90 min period (30-120 min after the meal) to the different meals were compared with that seen after a similar volume of low calorie drink. The thermic effects of glucose and protein were not significantly different between lean and obese subjects. Obese subjects showed very little increase in metabolic rate following ingestion of fat (-0.9 +/- 2.0%, mean +/- SEM) and this was significantly different from that seen in lean subjects (14.4 +/- 3.4%). The thermogenic response to mixed meal was also significantly lower in obese subjects when expressed as percentage change (12.9 +/- 2.3% compared to 25.0 +/- 4.8%). There was no evidence for delay in gastric emptying times for glucose and fatty meal in the six obese subjects in whom these were measured. We conclude that obese subjects show a reduced thermogenic response to fat.