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Background and Aim: Obesity affects cardiovascular risk and also quality of life (QoL). The aim of this study was to test weight loss and impact on QoL after sibutramine treatment in obese subjects., Methods: Double-blind randomized trial on 309 outpatients (51 males, 258 females; age 41.8 +/- 10.9 years, BMI 35.0 +/- 3.1 kg/m(2)) randomized to sibutramine (n = 154) or to placebo (n = 155) treatment. A combination of sibutramine 10 mg or matching placebo and a balanced hypocaloric diet was given for 6 months with monthly evaluations. The main outcome measures were weight loss, the impact of weight on QoL, BMI, and waist circumference., Results: The mean weight reduction was 8.2 kg in the sibutramine group and 3.9 in the placebo group at 6 months (p < 0.01). 40% of the sibutramine subjects and 14% of the control subjects lost > or =10% of their body weight (p < 0.01). The improvement in the impact of weight on QoL was statistically significant only in the sibutramine group at 6 months (mean -12.5 vs. -4.5 points; p < 0.01). In the sibutramine group the reduction in BMI (-3.1 vs. -1.4 kg/m(2)) and waist circumference (7.7 vs. 3.5 cm) was significantly greater (p < 0.001). The incidence of adverse events was low and similar to the placebo., Conclusions: This study confirmed that sibutramine significantly enhances the effect of diet on weight loss, BMI and waist circumference reduction, and showed a significant improvement of QoL., (Copyright 2007 S. Karger AG, Basel.)

Objective: To compare fasting total plasma homocysteine (tHcy) levels in vegans, lacto-ovovegetarians and control subjects, and to evaluate the relationships between tHcy levels and nutritional variables in vegetarians., Methods: The study was conducted on 45 vegetarian subjects: 31 vegans (19 males, 12 females, mean age 45.8 +/- 15.8 years); 14 lacto-ovovegetarians (6 males, 8 females, mean age 48.5 +/- 14.5 years), and 29 control subjects (19 males, 10 females, mean age 43.4 +/- 16.7 years). tHcy was evaluated by high-performance liquid chromatography. Serum vitamin B(12) and folate were analyzed by automated chemiluminescence systems. Clinical records, nutritional and anthropometric variables were collected for all vegetarian subjects., Results: tHcy was significantly higher in vegetarian subjects than in controls (23.9 +/- 21.3 vs. 11.6 +/- 4.9 micromol/l, p < 0.001). The prevalence of hyperhomocysteinemia was higher in vegetarians than in controls (53.3 vs. 10.3%, p < 0.001). Serum vitamin B(12) levels were lower in vegetarians than in control subjects (171.2 +/- 73.6 vs. 265.0 +/- 52.2 pmol/l, p < 0.01; normal range 220-740 pmol/l). In vegetarian subjects, significant inverse correlations were found between tHcy and serum vitamin B(12) levels (r = -0.776, p < 0.001) and between tHcy and serum folate levels (r = -0.340, p < 0.05). Positive correlations were found between tHcy and mean red cell volume (r = 0.44, p < 0.01) and between tHcy and fat-free mass (r = 0.36, p < 0.05)., Conclusion: Vegetarian subjects presented significantly higher tHcy levels, higher prevalence of hyperhomocysteinemia, and lower serum vitamin B(12) levels than controls., (Copyright 2002 S. Karger AG, Basel)

The purpose of our work is to compare the resting metabolic rate (RMR) and thermogenic effect of food (TEF) in a group of vegetarians and a group of subjects consuming a Mediterranean diet. The composition of the diets was similar. Thirty-two subjects were studied: 16 vegetarians (age 34 +/- 9 years, BMI 21 +/- 2) and 16 omnivors (age 30 +/- 5 years, BMI 22 +/- 3). All were in excellent general health. Each subject consumed a dish of pasta (100 g) and bread (30 g) after RMR had been measured. TEF was measured over the next 3 h and calculated as the incremental area above RMR. Energy (vegetarians and omnivors 7,727 +/- 3,516 vs 8,970 +/- 2,273 kJ/day, respectively) and carbohydrate (vegetarians and omnivors 285.1 +/- 141.3 vs. 300.1 +/- 74 g/day, respectively) intakes of the 2 groups were similar. The vegetarian group consumed a higher quantity of fiber (30.5 +/- 16.7 vs. 16.5 +/- 7.9) and a lower amount of protein (44.9 +/- 18.3 vs. 70.1 +/- 14.9) than the omnivorous group. No significant differences were observed in RMR (4.23 +/- 0.96 vs. 4.06 +/- 0.54 kJ/min) and TEF (0.50 +/- 0.25 vs. 0.38 +/- 0.25 Delta kJ/min) between the groups. Results did not change after correcting for weight, age and gender. Our study failed to show any significant differences in RMR and TEF between vegetarians and subjects consuming a Mediterranean diet. We conclude that vegetarianism per se is not accompanied by a difference in RMR and TEF when the carbohydrate content of the diet is similar to a control group of nonvegetarians.

Loss of body weight occurs during high mountain expeditions but whether it is due to inadequate diet or other factors is unknown. Moreover the composition of the weight loss is unclear. The aim of our study was to compare the nutritional, anthropometric and metabolic changes during a mountaineering expedition in two groups of climbers, whose dietary energy intake was ad libitum, one given a lacto-fish-ovo-vegetarian diet and one an omnivorous diet. The intake of various nutrients, body weight, body composition and metabolic variables were evaluated before and during high altitude exposure and after the return to low altitude. The two groups were matched for age, body mass index and gender. No significant differences were found for nutritional variables between the two groups. Energy, animal and vegetable protein and fiber intake were significantly lower at climbing quote than before the beginning of the expedition. Significant differences between before the beginning and base camp in all variables were found. Energy and animal protein intake, but not vegetable protein and fiber intake, were significantly lower at climbing quote than at base camp. All subjects significantly reduced body weight, body mass index, waist and hip circumferences but not fat-free mass and fat mass. Metabolic variables significantly improved after the mountaineering expedition. Our study seems to confirm that a mountaineering expedition decreases energy and protein intake, reduces body weight and improves metabolic variables. Because our subjects spontaneously tended to have the same food intake despite the different dietary recommendations, our study failed to observe any differences between the two groups. However, our study shows that a low protein diet, in which the type of protein is mostly vegetable protein, could be adapted for climbers determining only a small decrease of fat-free mass.

The concentration of high-density lipoprotein (HDL) cholesterol in patients with severe obesity is generally subnormal. The exact mechanism linking obesity with reduced levels of HDL cholesterol remains unclear. In this study we evaluated the postheparin plasma lipolytic enzymes lipoprotein lipoprotein lipase (LPL) and hepatic lipase (HL) in a group of 24 obese women compared with controls and analyzed the interrelationships between insulin, postheparin lipolytic enzymes and HDL subfractions. Total HDL cholesterol was significantly lower in the obese subjects than in the controls, and the difference was mainly due to HDL2 cholesterol concentrations. Mean fasting glucose, insulin and the summated means of glucose (sigma glucose) after the oral glucose tolerance test (OGTT) were not significantly different in the two groups. The summated means of insulin (sigma IRI) after the OGTT were significantly higher in the obese women than in the controls. LPL, HL and the HL-to-LPL ratio were significantly higher in the obese women than in the controls. HL and LPL correlated positively with sigma glucose, sigma IRI and body mass index (BMI) and negatively with plasma triglycerides. Partial correlation analysis demonstrated that, when exposed to similar sigma IRI values, HL and LPL were no longer correlated with sigma glucose, plasma triglycerides and BMI. HDL2 cholesterol levels were negatively correlated with HL, posthepatic plasma lipolytic activity, sigma glucose, plasma triglycerides and BMI. HDL2 cholesterol concentrations were directly correlated with LPL. Partial correlation analysis showed that when exposed to similar HL and LPL values, HDL2 cholesterol values were no longer correlated with sigma glucose, sigma IRI, plasma triglycerides and BMI. Therefore, our results demonstrate that the low HDL2 cholesterol levels found in obese women may be related to the high levels of HL and to the high HL-to-LPL ratio which in turn could be determined by the peripheral insulin resistance.

The influence of caloric restriction and of weight loss during a weight-maintaining diet on lipid profile and in particular on high density lipoprotein (HDL) is controversial. In this study we analyzed the effect of a period of very low caloric diet (VLCD) and of a period of hypocaloric diet followed by 30 days of weight stabilization on lipoprotein levels, especially on HDL cholesterol and its subfractions (HDL2 and HDL3) and on the summated means of glucose (sigma glucose) and insulin levels (sigma IRI) after an oral tolerance test in a group of obese females. Body weight decreased significantly during the VLCD and hypocaloric diet. Total cholesterol decreased significantly after the VLCD and hypocaloric diet, but after the period of the weight-maintaining diet it was superimposable to the initial value. Very low density lipoprotein (VLDL) and low density lipoprotein (LDL) cholesterol behaved like total cholesterol. HDL2, HDL3 and HDL cholesterol decreased significantly after the period of VLCD. Then, after the hypocaloric diet the values of HDL2, HDL3 and HDL cholesterol returned towards the initial values and only after the period of the weight-maintaining diet did their values increase significantly. sigma glucose did not vary significantly at any time of the study, while sigma IRI reduced significantly both after the hypocaloric diet and the weight-maintaining diet. HDL2 and HDL cholesterol changes were found to be positively correlated to the variations of sigma IRI both at day 45 and 75 of the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Using computed tomography on 19 obese female subjects, we determined abdominal adipose tissue, both subcutaneous and visceral adipose tissue, before and after 2 weeks of a very low caloric diet (VLCD). The following parameters were also determined before and after 15-20 days of VLCD: plasma glucose and insulin levels, oral glucose tolerance test, basal pancreatic insulin secretion estimated by fasting C peptide (Cp), and fasting insulin hepatic clearance calculated by Cp/insulin molar ratio. After VLCD the body weight and body mass index significantly declined (p less than 0.01); whereas abdominal adipose tissue and visceral abdominal tissue (VAT) significantly decreased (p less than 0.01), modifications of subcutaneous abdominal tissue (SAT) were not significant. Fasting insulin levels and plasma glucose response to oral glucose load significantly decreased (p less than 0.05). Insulin response remained unchanged. Cp immunoreactive insulin (IRI) significantly increased (p less than 0.01). A significant positive correlation was found between delta VAT and delta Cp/IRI before and after VLCD (p less than 0.01). Our data seem to suggest that the weight loss induced by VLCD fundamentally involves a decrease in VAT. The reduction in visceral fat could be associated with an increase in hepatic insulin clearance.

Alterations in the relative proportions of very low density lipoprotein (VLDL) apoprotein C-III (apoC-III) isoforms have been previously observed under various dietary and metabolic states. This study was designed to evaluate the effects of a very high caloric restriction on plasma triglycerides and on the relative proportions of VLDL apoprotein C-II (apoC-II) and apoC-III isoforms in obese subjects. VLDL were isolated by preparative ultra-centrifugation from 12 obese women. ApoC-II and apoC-III subspecies were separated by analytical ultrathin-layer isoelectrofocusing. The mean body weight decreased significantly from 96.2 +/- 8.7 to 90.6 +/- 7.6 kg (p less than 0.01). Mean total and VLDL triglycerides did not vary significantly. Apoprotein C-III2 (apoC-III2) as percentage of total apoprotein C increased (p less than 0.01) and apoprotein CIII0 (apoC-III0) decreased (p less than 0.01). Apoprotein C-III1 (apoC-III1) did not vary significantly. An inverse correlation was found between the percentage variation of apoC-III2 and that of apoC-III1 (r = -0.94; p less than 0.01). The variations of apoC-III2 correlated positively (r = 0.83; p less than 0.01), while those of apoC-III1 correlated inversely (r = -0.65, p less than 0.025) with the changes of VLDL triglycerides. The apoC-III1 to apoC-III2 ratio as well as the apoC-III0 to apoC-III2 and apo C-III1 ratios decreased after diet (p from less than 0.01 to less than 0.001). Total apoC-III as well as apoC-III2 and apoC-III1 to apoC-II ratios did not vary.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of a very low caloric diet (VLCD) on high density lipoproteins (HDL) is controversial. This study was designed to evaluate the influence of a VLCD on lipids and lipoproteins, especially on HDL subfractions (HDL2, HDL3) in obese women. After a 4-day period of isocaloric standard diet, 30 women at least 50% above ideal body weight were switched for 15 days on a protein-sparing modified diet providing 1.57 MJ per day. Mean body weight reduction was 5.6 +/- 0.7 kg. After the VLCD, total, very low density lipoproteins (VLDL), low density lipoproteins (LDL) and HDL cholesterol significantly decreased in all the subjects (p less than 0.01). Both HDL subfractions were depressed after the VLCD (p less than 0.01) but the reduction occurred predominantly in the HDL2 subfraction, thus inducing a decrease in the HDL2 to HDL3 cholesterol ratio (p less than 0.01). The VLCD was associated with a slight but not significant increase in the LDL to HDL cholesterol ratio. This increase was due mostly to the rise in the LDL to HDL2 cholesterol ratio (p less than 0.01). Further studies are needed to evaluate the long-term changes of HDL subfractions during weight-reducing regimens.

The influence of caloric restriction on lipid profile is controversial. This study was designed to evaluate the influence of dietary proteins from different sources on lipoprotein levels in obese subjects during a period of very low-caloric diet followed by 60 days of hypocaloric diet. The subjects were 24 obese patients aged 25-42 of at least 50% above ideal weight. The patients were separated into two groups and received for 15 days 375 kcal/day on the assumption that commercial textured preparations contained the same amount of proteins, respectively, as casein (group A) or soy protein (group B). Then the very low-caloric diet of the two groups was integrated with 425 kcal/day for 60 days. Body weight reduction was equivalent in the two groups. Total plasma cholesterol decreased significantly in both groups after the two periods of diet, but the percent variations were always significantly higher in the group B than in A. Total plasma triglycerides reduced significantly only in the group B. Very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) cholesterol behaved as total cholesterol in the two groups. High-density lipoprotein (HDL) cholesterol diminished significantly only after the 15 days of very low-caloric diet in group B, while it decreased throughout the diet in group A. The decrease of HDL cholesterol was mainly due to the HDL2 subfraction. The results of our study show that the substitution of soy protein for casein can be of benefit in those patients who need a long-term hypocaloric diet.