Multinutrient supplement containing ephedra and caffeine causes weight loss and improves metabolic risk factors in obese women: a randomized controlled trial

OBJECTIVE: To determine the safety and efficacy of a dietary supplement with a low dose of ephedra and caffeine in overweight/obese premenopausal female subjects. DESIGN: A 9-month, double-blind, randomized control study compared the efficacy and safety of a dietary supplement with ephedra and caffeine to a control supplement. SUBJECTS: Sixty-one healthy, premenopausal women with body mass index (BMI) from 27 to 39 kg/m2 were randomly assigned and received a dietary supplement (40 mg/day ephedra alkaloids, 100 mg/day caffeine, high potency mixture of vitamins, minerals, omega-3 fatty acids) or a control supplement for 9 months. MEASUREMENTS: Efficacy: changes in body weight, body composition, lipids, insulin, leptin, adiponectin, ghrelin, and self-reports of physical activity, diet and quality of life indices. Safety: blood pressure, heart rate, electrocardiograms, urinalysis, blood histology, serum chemistry measures and self-reported symptoms. RESULTS: Forty-one women completed the study. The treatment group lost significantly more body weight (-7.18 kg) and body fat (-5.33 kg) than the control group (-2.25 and -0.99 kg, respectively), and showed significant declines in heart rate, serum cholesterol, triglycerides, cholesterol to high-density lipoprotein ratio, glucose, fasting insulin, and leptin. Blood pressure, electrocardiograms, other clinical chemistry measures, blood histology, urinalysis, and self-reported physical activity were similar in the groups. Minor symptoms included dry mouth, insomnia, nervousness and palpitations. The treatment group reported more energy and decreased appetite compared to controls and scored higher on a quality of life domain assessing vitality. CONCLUSION: A dietary supplement containing a low potency ephedra/caffeine mixture appeared safe and effective in causing loss of weight and body fat, and improving several metabolic parameters, including insulin sensitivity and lipid profiles when tested under physician supervision. Such supplements could be a useful tool to assist with weight loss.     

Metabolic risk factors in formerly obese women--effects of a pronounced weight loss by gastric band operation compared with weight loss by diet alone

AIM: The aim of the present study was to evaluate differences in the metabolic risk profile in formerly obese women, in whom a significant weight loss was obtained by Swedish adjustable gastric band (SAGB) operation or by diet alone. METHODS: A total of 40 patients (24 after SAGB and 16 after diet) participated in the study. Clinical data, including body mass index (BMI), waist-to-hip ratio, body fat content and blood pressure values, as well as laboratory results [fasting glucose, insulin, homeostasis model assessment (HOMA) index, leptin, lipid values and markers of subclinical inflammation] were evaluated before a planned abdominoplastic operation. RESULTS: Patients in the SABG group had lost a significantly greater amount of weight (52.7 +/- 10.0 kg) compared with the diet group (20.0 +/- 11.5 kg; p < 0.001), and the percent excess weight loss was 69.1 +/- 11.4 in the SAGB group and 54.5 +/- 17.7 (p < 0.040) in the diet group. Before the abdominoplastic operation neither the mean BMI nor the percentage of fat mass revealed a significant difference between the groups. Fasting insulin (6.1 +/- 3.0 microU/ml) and the HOMA index (1.4 +/- 0.7) as a measure of insulin resistance were significantly lower in the SAGB than in the diet group (fasting insulin: 8.2 +/- 3.8 microU/ml; p < 0.048; HOMA index: 2.0 +/- 1.0; p < 0.031). Swedish adjustable gastric band patients showed significantly lower plasma leptin levels (9.4 +/- 10.8 ng/ml) than the dietary-treated patients (13.9 +/- 9.6 ng/ml; p < 0.014), while tumour necrosis factor-alpha serum levels were increased in the SAGB group (17.6 +/- 7.3 pg/ml) compared with the diet group (11.9 +/- 0.49 pg/l; p < 0.048). CONCLUSIONS: The extensive weight loss in formerly obese women after SAGB operation was paralleled by a favourable metabolic profile indicating a higher degree of insulin sensitivity than in women after a successful, but less pronounced weight loss by diet alone.     

Comparison of a low-fat diet to a low-carbohydrate diet on weight loss, body composition, and risk factors for diabetes and cardiovascular disease in free-living, overweight men and women

Overweight and obese men and women (24-61 yr of age) were recruited into a randomized trial to compare the effects of a low-fat (LF) vs. a low-carbohydrate (LC) diet on weight loss. Thirty-one subjects completed all 10 wk of the diet intervention (retention, 78%). Subjects on the LF diet consumed an average of 17.8% of energy from fat, compared with their habitual intake of 36.4%, and had a resulting energy restriction of 2540 kJ/d. Subjects on the LC diet consumed an average of 15.4% carbohydrate, compared with habitual intakes of about 50% carbohydrate, and had a resulting energy restriction of 3195 kJ/d. Both groups of subjects had significant weight loss over the 10 wk of diet intervention and nearly identical improvements in body weight and fat mass. LF subjects lost an average of 6.8 kg and had a decrease in body mass index of 2.2 kg/m2, compared with a loss of 7.0 kg and decrease in body mass index of 2.1 kg/m2 in the LC subjects. The LF group better preserved lean body mass when compared with the LC group; however, only the LC group had a significant decrease in circulating insulin concentrations. Group results indicated that the diets were equally effective in reducing systolic blood pressure by about 10 mm Hg and diastolic pressure by 5 mm Hg and decreasing plasminogen activator inhibitor-1 bioactivity. Blood beta-hydroxybutyrate concentrations were increased in the LC only, at the 2- and 4-wk time points. These data suggest that energy restriction achieved by a very LC diet is equally effective as a LF diet strategy for weight loss and decreasing body fat in overweight and obese adults.     

Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials

BACKGROUND: Low-carbohydrate diets have become increasingly popular for weight loss. However, evidence from individual trials about benefits and risks of these diets to achieve weight loss and modify cardiovascular risk factors is preliminary. METHODS: We used the Cochrane Collaboration search strategy to identify trials comparing the effects of low-carbohydrate diets without restriction of energy intake vs low-fat diets in individuals with a body mass index (calculated as weight in kilograms divided by the square of height in meters) of at least 25. Included trials had to report changes in body weight in intention-to-treat analysis and to have a follow-up of at least 6 months. Two reviewers independently assessed trial eligibility and quality of randomized controlled trials. RESULTS: Five trials including a total of 447 individuals fulfilled our inclusion criteria. After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets (weighted mean difference, -3.3 kg; 95% confidence interval [CI], -5.3 to -1.4 kg). This difference was no longer obvious after 12 months (weighted mean difference, -1.0 kg; 95% CI, -3.5 to 1.5 kg). There were no differences in blood pressure. Triglyceride and high-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-carbohydrate diets (after 6 months, for triglycerides, weighted mean difference, -22.1 mg/dL [-0.25 mmol/L]; 95% CI, -38.1 to -5.3 mg/dL [-0.43 to -0.06 mmol/L]; and for high-density lipoprotein cholesterol, weighted mean difference, 4.6 mg/dL [0.12 mmol/L]; 95% CI, 1.5-8.1 mg/dL [0.04-0.21 mmol/L]), but total cholesterol and low-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-fat diets (weighted mean difference in low-density lipoprotein cholesterol after 6 months, 5.4 mg/dL [0.14 mmol/L]; 95% CI, 1.2-10.1 mg/dL [0.03-0.26 mmol/L]). CONCLUSIONS: Low-carbohydrate, non-energy-restricted diets appear to be at least as effective as low-fat, energy-restricted diets in inducing weight loss for up to 1 year. However, potential favorable changes in triglyceride and high-density lipoprotein cholesterol values should be weighed against potential unfavorable changes in low-density lipoprotein cholesterol values when low-carbohydrate diets to induce weight loss are considered.     

Effect of the Mediterranean diet with and without weight loss on cardiovascular risk factors in men with the metabolic syndrome

Background and aims

No study has yet examined how weight loss modifies the impact of the Mediterranean diet (MedDiet) on cardiovascular risk factors in men with the metabolic syndrome (MetS). The objective of the study was to assess the efficacy of MedDiet, with and without weight loss, to modify the cardiometabolic risk profile of male patients with MetS.

Methods and results

Twenty-six men aged between 24 and 62 years with the MetS consumed a North American control diet for 5 weeks followed by a 5-week MedDiet, both under weight-maintaining conditions. Participants then underwent a 20-week weight loss period, after which they consumed the MedDiet for five weeks under weight stable conditions. Body weight was reduced by 10.2% ± 2.9% after the weight loss period (p < 0.001). All foods were provided to participants during the weight stable phases of the study. The MedDiet in the absence of weight loss decreased total plasma cholesterol (C) (−7.1%), LDL-C (−9.3%) and the total/HDL-C ratio (−6.5%) compared to the control diet (all p < 0.04). The MedDiet combined with weight loss led to reductions in systolic blood pressure (−4.7%), diastolic blood pressure (−7.7%), triglycerides (−18.2%), ApoB (−10.7%), fasting glucose (−4.2%) and insulin (−29.9%) compared to the control diet (all p < 0.001). Conclusion: The MedDiet in the absence of weight loss leads to significant changes in plasma cholesterol concentrations but has little effects on other cardiometabolic risk factors associated with the MetS in men.     

High-fibre, low-fat diet predicts long-term weight loss and decreased type 2 diabetes risk: the Finnish Diabetes Prevention Study

Aims/hypothesis The aim of this study was to investigate the association of dietary macronutrient composition and energy density with the change in body weight and waist circumference and diabetes incidence in the Finnish Diabetes Prevention Study.Subjects and methods Overweight, middle-aged men (n=172) and women (n=350) with impaired glucose tolerance were randomised to receive either ‘standard care’ (control) or intensive dietary and exercise counselling. Baseline and annual examinations included assessment of dietary intake with 3-day food records and diabetes status by repeated 75-g OGTTs. For these analyses the treatment groups were combined and only subjects with follow-up data (n=500) were included.Results Individuals with low fat (<median) and high fibre (>median) intakes lost more weight compared with those consuming a high-fat (>median), low-fibre (<median) diet (3.1 vs 0.7 kg after 3 years). In separate models, hazard ratios for diabetes incidence during a mean follow-up of 4.1 years were (highest compared with lowest quartile) 0.38 (95% CI 0.19–0.77) for fibre intake, 2.14 (95% CI 1.16–3.92) for fat intake, and 1.73 (95% CI 0.89–3.38) for saturated-fat intake, after adjustment for sex, intervention assignment, weight and weight change, physical activity, baseline 2-h plasma glucose and intake of the nutrient being investigated. Compared with the low-fat/high-fibre category, hazard ratios were 1.98 (95% CI 0.98–4.02), 2.68 (95% CI 1.40–5.10), and 1.89 (95% CI 1.09–3.30) for low-fat/low-fibre, high-fat/high-fibre, and high-fat/low-fibre, respectively.Conclusions/interpretation Dietary fat and fibre intake are significant predictors of sustained weight reduction and progression to type 2 diabetes in high-risk subjects, even after adjustment for other risk factors.     

Long-term weight loss decreases the nontraditional cardiovascular risk factors interleukin-18 and matrix metalloproteinase-9 in obese subjects

The objective of the study was to investigate the effect of long-term (3.2 years) weight loss on serum levels of the nontraditional cardiovascular risk factors interleukin (IL)-18 and matrix metalloproteinase (MMP)-9. Moreover, we wanted to assess the significance of the magnitude of the weight loss and evaluate the potential effects of 36 months of treatment with the lipase inhibitor orlistat on these parameters. Sixty-eight abdominally obese subjects completed 8 weeks of very low energy diet (600-800 kcal/d) followed by 36 months of randomized treatment with either orlistat or placebo together with lifestyle intervention. Serum levels of IL-18, MMP-9, and leptin were measured by flowmetric xMAP technology (Luminex, Austin, TX). Changes in the levels of IL-18, MMP-9, and leptin were similar in the orlistat and the placebo group during this study. Thus, the 2 groups were combined for further analysis. A weight loss of 8.4 ± 8.8 kg from baseline to 3.2 years was associated with significant decreases in IL-18 (P < .001), MMP-9 (P < .01), and leptin (P < .001). Matrix metalloproteinase-9 was, however, significantly increased after 8 weeks of very low energy diet-induced weight loss (P < .05). The long-term changes in IL-18 were significantly associated with changes in body mass index independent of changes in blood pressure and lipids (P < .05). Levels and changes of IL-18 and MMP-9 were significantly positively associated at 3.2 years (P < .01). Long-term changes in leptin were significantly associated with changes in IL-18 (P < .01) at 3.2 years. Diet-induced long-term weight loss decreased IL-18 and MMP-9. The decrease in IL-18 was associated with changes in body mass index independent of changes in blood pressure and lipids, indicating that even a minor weight reduction (>5%) has beneficial effects on nontraditional cardiovascular risk markers. Orlistat treatment had no independent effects on IL-18, MMP-9, or leptin in the present study.     

Efficacy of weight loss drugs on obesity and cardiovascular risk factors in obese adolescents: a meta‐analysis of randomized controlled trials

Weight loss drugs have been developed to reduce the comorbidities associated with excess weight. We conducted a meta‐analysis of the efficacy of orlistat and sibutramine on weight, body mass index, waist circumference and cardiovascular risk factors in overweight adolescents. MEDLINE and the Cochrane Library were searched for relevant articles using MESH terms and keywords. Studies were included if they had reported quantitative estimates and standard deviations of the association between each weight loss drug and weight, with information on at least one cardiovascular risk factor. A total of eight trials (three orlistat and five sibutramine) with information on 1391 individuals was included in the present analysis. The mean decrease in weight between the intervention and control groups was 5.25 kg (95% confidence interval: 3.03–7.48) after a minimum follow‐up of 6 months. There was evidence of statistical heterogeneity between the studies (I² = 76%) that was no longer apparent after exclusion of trials of orlistat (mean weight decrease = 5.32 kg; I² = 38%). There was little evidence that treatment was associated with adverse effects on cardiovascular risk factors but this requires verification from future large trials with longer study follow‐up.     

Effect of weight loss resulting from a combined low-fat diet/exercise regimen on low-density lipoprotein particle size and distribution in obese women

Weight loss resulting from diet interventions has been shown to favorably affect low-density lipoprotein (LDL) particle size and distribution, and, hence, decrease cardiovascular disease risk. However, the effect of a dietary weight loss strategy when combined with exercise, on LDL electrophoretic characteristics, has yet to be tested. This study examined the effect of a weight loss intervention that combined a low-fat diet with moderate endurance training, on LDL particle size and distribution in obese women. Thirty obese, hypercholesterolemic women participated in a controlled longitudinal weight loss trial, which consisted of (1) a 2-week pre-stabilization phase, (2) a 20-week weight loss phase, and (3) a 2-week post-stabilization phase. Weight reduction resulted from a low-fat diet (<30% fat, 50%-60% carbohydrate, 20% protein) combined with an endurance training program (>40 minutes moderate training, 3 times per week). Mean weight loss was 14.8% (P < .01) of initial body weight. Total, LDL cholesterol, and triacylglycerol concentrations decreased (P < .01) by 8.9%, 7.5%, and 27.1%, respectively, whereas high-density lipoprotein cholesterol concentrations increased (P < .01) by 9.9%. No significant differences were noted for LDL peak or integrated particle size. The relative proportion of small, medium, and large particles was not significantly different posttreatment. Estimated cholesterol concentrations in large- and medium-sized LDL particles decreased (P < .05) by 15.3% and 5.9%, respectively, as a result of weight loss. No effect was noted for estimated cholesterol concentrations in small size LDL particles. In conclusion, these findings suggest that weight loss, resulting from a low-fat diet/exercise program, has only a minimal effect on LDL particle size and distribution.     

In type 2 diabetes, randomisation to advice to follow a low-carbohydrate diet transiently improves glycaemic control compared with advice to follow a low-fat diet producing a similar weight loss

Aims/hypothesis  

The study aimed to compare the effects of a 2 year intervention with a low-fat diet (LFD) or a low-carbohydrate diet (LCD), based on four group meetings to achieve compliance.     

Consumption of cod and weight loss in young overweight and obese adults on an energy reduced diet for 8-weeks

Background and aimsIn a cross-European study it was recently shown that consumption of cod increases weight loss in men and also has other positive health effects. The aim of this study was to investigate whether cod consumption increases weight loss and improves cardiovascular risk factors in a dose dependent manner during an 8-week energy restriction diet in young overweight and obese healthy adults.Methods and resultsIn this dietary intervention 126 subjects (20–40 years, BMI 27.5–32.5 kg/m²) comprised the group given energy-restricted diets (−30%); they were prescribed an identical macronutrient composition but different amounts of cod: the control group were given no seafood; group 1 were given 150 g cod 3 times a week; and group 2 were given 150 g cod 5 times a week. Anthropometric measurements and cardiovascular risk factors were assessed at baseline and endpoint. Body weight decreased after 8-weeks (5.0 ± 2.9 kg, P < 0.001), also waist circumference (5.0 ± 3.2 cm, P < 0.001), BMI (1.65 ± 0.95 kg, P < 0.001), systolic (3.4 ± 8.9 mmHg, P = 0.001) and diastolic blood pressure (2.4 ± 6.9 mmHg, P < 0.001), triglycerides (1.26 ± 0.567 mmol/L, P = 0.030) and insulin (1.21 ± 5.31 mU/L, P = 0.025). The prevalence of the metabolic syndrome dropped from 29 to 21%. According to linear models weight loss was 1.7 kg greater among subjects consuming 150 g 5×/week compared to the control group (P < 0.015). The trend analysis supported a dose-response relationship between cod consumption and weight loss (P < 0.001), but changes of other measured cardiovascular risk factors were similar between the groups.ConclusionA dose-response relationship between cod consumption and weight loss during an 8-week energy restriction diet is found and 5 × 150 g cod/week results in 1.7 kg greater weight loss in young overweight or obese adults than a isocaloric diet without seafood.     

Sequential effects of arobic exercise training and weight loss on risk factors for coronary disease in healthy, obese middle-aged and older men

The relative benefits of weight loss (WL) versus aerobic exercise training (AEX) on cardiac risk factors in obese individuals remain controversial. In this study, we examined the effects of the sequential interventions of 9 months of AEX followed by weight loss with continued AEX (AEX + WL) on cardiac risk factors in 21 obese (body fat, 29.5% ± 0.8%, mean ± SEM) middle-aged and older men. AEX increased the maximal aerobic capacity ([Vo₂max] in liters per minute) of these men by 14% (P < .001), with no significant change in weight. AEX did not improve blood pressure (BP) or oral glucose tolerance, and had no significant effect on lipid concentrations. During the AEX + WL intervention, the 21 men lost 8.1 ± 0.6 kg. Despite continued training, there was no fruther increase in Vo₂max during this intervention. Compared with AEX, AEX + WL decreased glucose and insulin responses during the oral glucose tolerance test (OGTT) by 8% (P < .05) and 30% (P < .01), respectively. AEX + WL reduced plasma triglyceride (TG) by 17% (P < .05) and low-density lipoprotein cholesterol (LDL-C) by 8% (P < .01) and increased high-density lipoprotein cholesterol (HDL-C) by 11% (3.7 mg/dL, P < .01). The sequential interventions resulted in a 20% decrease in the . The results demonstrate that AEX + WL had a more substantial impact than AEX alone on glucose tolerance and lipoprotein concentrations. Physicians should encourage obese patients to become physically active and lose weight to improve their cardiac risk factor profile.     

Comparison of the effects of 52 weeks weight loss with either a high-protein or high-carbohydrate diet on body composition and cardiometabolic risk factors in overweight and obese males

Background:

A high-protein (HP), low-fat weight-loss diet may be advantageous for improving cardiometabolic health outcomes and body composition. To date, only limited research has been conducted in male participants.

Objective:

To evaluate the medium to long-term effects of two, low-fat, hypocaloric diets differing in carbohydrate:protein ratio on body composition and cardiometabolic health outcomes in overweight and obese males.

Design:

One hundred and twenty males (age 50.8±9.3 (s.d.) years, body mass index 33.0±3.9 kg m⁻²) were randomly assigned and consumed a low-fat, isocaloric, energy-restricted diet (7 MJ per day) with either HP (protein:carbohydrate:fat %energy, 35:40:25) or high carbohydrate (HC; 17:58:25). Body weight, body composition and cardiometabolic risk factors were assessed at baseline and after 12 and 52 weeks.

Results:

Sixty-eight participants completed the study (HP, n=33; HC, n=35). At 1 year both the groups experienced similar reductions in body weight (HP, −12.3±8.0 kg (−12%); HC, −10.9±8.6 kg (−11%); P=0.83 time × group interaction) and fat mass (−9.9±6.0 kg (−27%) vs −7.3±5.8 kg (−22%); P=0.11). Participants who consumed the HP diet lost less fat-free mass (−2.6±3.7 kg (−4%) vs −3.8±4.7 kg (−6%); P<0.01). Both groups experienced similar increases in high-density lipoprotein cholesterol (8%) and reductions in total cholesterol (−7%), low-density lipoprotein cholesterol (−9%), triglycerides (−24%), glucose (−3%), insulin (−38%), blood pressure (−7/−12%) and C-reactive protein (−29%), (P⩾0.14).

Conclusion:

In overweight and obese men, both a HP and HC diet reduced body weight and improved cardiometabolic risk factors. Consumption of a HP diet was more effective for improving body composition compared with an HC diet.     

Portion control plate for weight loss in obese patients with type 2 diabetes mellitus: a controlled clinical trial

BACKGROUND: Portion size is an important determinant of energy intake. To our knowledge, no randomized controlled trial has evaluated the efficacy of portion control tools to induce weight loss. In patients with type 2 diabetes mellitus, weight reduction improves glycemic control. METHODS: We randomly assigned 130 obese patients with type 2 diabetes mellitus (including 55 patients taking insulin) to the daily use of a commercially available portion control plate for 6 months (intervention group) vs to usual care in the form of dietary teaching (usual care control group). RESULTS: Follow-up was 93.8%. Patients in the intervention group lost significantly more weight than control subjects (mean+/-SD, 1.8%+/-3.9% vs 0.1%+/-3.0%, P=.006). Compared with controls, more patients in the intervention group required a decrease in their diabetes medications at 6 months (26.2% vs 10.8%, P=.04). CONCLUSIONS: Compared with usual care, the portion control tool studied was effective in inducing weight loss. The portion control plate also enabled patients with diabetes mellitus to decrease their hypoglycemic medications without sacrificing glycemic control. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00254124.     

Metabolic effects of weight loss on a very-low-carbohydrate diet compared with an isocaloric high-carbohydrate diet in abdominally obese subjects.

OBJECTIVES: This study was designed to compare the effects of an energy-reduced, isocaloric very-low-carbohydrate, high-fat (VLCHF) diet and a high-carbohydrate, low-fat (HCLF) diet on weight loss and cardiovascular disease (CVD) risk outcomes. BACKGROUND: Despite the popularity of the VLCHF diet, no studies have compared the chronic effects of weight loss and metabolic change to a conventional HCLF diet under isocaloric conditions. METHODS: A total of 88 abdominally obese adults were randomly assigned to either an energy-restricted (approximately 6 to 7 MJ, 30% deficit), planned isocaloric VLCHF or HCLF diet for 24 weeks in an outpatient clinical trial. Body weight, blood pressure, fasting glucose, lipids, insulin, apolipoprotein B (apoB), and C-reactive protein (CRP) were measured at weeks 0 and 24. RESULTS: Weight loss was similar in both groups (VLCHF -11.9 +/- 6.3 kg, HCLF -10.1 +/- 5.7 kg; p = 0.17). Blood pressure, CRP, fasting glucose, and insulin reduced similarly with weight loss in both diets. The VLCHF diet produced greater decreases in triacylglycerols (VLCHF -0.64 +/- 0.62 mmol/l, HCLF -0.35 +/- 0.49 mmol/l; p = 0.01) and increases in high-density lipoprotein cholesterol (HDL-C) (VLCHF 0.25 +/- 0.28 mmol/l, HCLF 0.08 +/- 0.17 mmol/l; p = 0.002). Low-density lipoprotein cholesterol (LDL-C) decreased in the HCLF diet but remained unchanged in the VLCHF diet (VLCHF 0.06 +/- 0.58 mmol/l, HCLF -0.46 +/- 0.71 mmol/l; p < 0.001). However, a high degree of individual variability for the LDL response in the VLCHF diet was observed, with 24% of individuals reporting an increase of at least 10%. The apoB levels remained unchanged in both diet groups. CONCLUSIONS: Under isocaloric conditions, VLCHF and HCLF diets result in similar weight loss. Overall, although both diets had similar improvements for a number of metabolic risk markers, an HCLF diet had more favorable effects on the blood lipid profile. This suggests that the potential long-term effects of the VLCHF diet for CVD risk remain a concern and that blood lipid levels should be monitored. (Long-term health effects of high and low carbohydrate, weight loss diets in obese subjects with the metabolic syndrome; http://www.anzctr.org.au; ACTR No. 12606000203550).     

The role of energy expenditure in the differential weight loss in obese women on low-fat and low-carbohydrate diets

We have recently reported that obese women randomized to a low-carbohydrate diet lost more than twice as much weight as those following a low-fat diet over 6 months. The difference in weight loss was not explained by differences in energy intake because women on the two diets reported similar daily energy consumption. We hypothesized that chronic ingestion of a low-carbohydrate diet increases energy expenditure relative to a low-fat diet and that this accounts for the differential weight loss. To study this question, 50 healthy, moderately obese (body mass index, 33.2 +/- 0.28 kg/m(2)) women were randomized to 4 months of an ad libitum low-carbohydrate diet or an energy-restricted, low-fat diet. Resting energy expenditure (REE) was measured by indirect calorimetry at baseline, 2 months, and 4 months. Physical activity was estimated by pedometers. The thermic effect of food (TEF) in response to low-fat and low-carbohydrate breakfasts was assessed over 5 h in a subset of subjects. Forty women completed the trial. The low-carbohydrate group lost more weight (9.79 +/- 0.71 vs. 6.14 +/- 0.91 kg; P < 0.05) and more body fat (6.20 +/- 0.67 vs. 3.23 +/- 0.67 kg; P < 0.05) than the low-fat group. There were no differences in energy intake between the diet groups as reported on 3-d food records at the conclusion of the study (1422 +/- 73 vs. 1530 +/- 102 kcal; 5954 +/- 306 vs. 6406 +/- 427 kJ). Mean REE in the two groups was comparable at baseline, decreased with weight loss, and did not differ at 2 or 4 months. The low-fat meal caused a greater 5-h increase in TEF than did the low-carbohydrate meal (53 +/- 9 vs. 31 +/- 5 kcal; 222 +/- 38 vs. 130 +/- 21 kJ; P = 0.017). Estimates of physical activity were stable in the dieters during the study and did not differ between groups. These results confirm that short-term weight loss is greater in obese women on a low-carbohydrate diet than in those on a low-fat diet even when reported food intake is similar. The differential weight loss is not explained by differences in REE, TEF, or physical activity and likely reflects underreporting of food consumption by the low-fat dieters.     

Randomization to a low-carbohydrate diet advice improves health related quality of life compared with a low-fat diet at similar weight-loss in Type 2 diabetes mellitus

AimsTo compare the effects on health-related quality of life (HRQoL) of a 2-year intervention with a low-fat diet (LFD) or a low-carbohydrate diet (LCD) based on four group-meetings to achieve compliance. To describe different aspects of taking part in the intervention following the LFD or LCD.MethodsProspective, randomized trial of 61 adults with Type 2 diabetes mellitus. The SF-36 questionnaire was used at baseline, 6, 12 and 24 months. Patients on LFD aimed for 55–60 energy percent (E%) and those on LCD for 20 E% from carbohydrates. The patients were interviewed about their experiences of the intervention.ResultsMean body-mass-index was 32.7 ± 5.4 kg/m² at baseline. Weight-loss did not differ between groups and was maximal at 6 months, LFD: −3.99 ± 4.1 kg, LCD: −4.31 ± 3.6 kg (p < 0.001 within groups). There was an increase in the physical component score of SF-36 from 44.1 (10.0) to 46.7 (10.5) at 12 months in the LCD group (p < 0.009) while no change occurred in the LFD group (p < 0.03 between groups). At 12 months the physical function, bodily pain and general health scores improved within the LCD group (p values 0.042–0.009) while there was no change within the LFD group.ConclusionsWeight-changes did not differ between the diet groups while improvements in HRQoL only occurred after one year during treatment with LCD. No changes of HRQoL occurred in the LFD group in spite of a similar reduction in body weight.