Dietary herbal supplements with phenylephrine for weight loss

This study was designed to evaluate the efficacy and safety of a dietary herbal supplement containing citrus aurantium and phenylephrine in the treatment of obesity. Two pilot studies enrolled healthy subjects with body mass indexes 25-40 kg/m(2) to similar 8-week weight loss programs. Safety was assessed by physical examination and laboratory tests at screening and 8 weeks. The first pilot study randomized eight subjects to citrus aurantium (herbal phenylephrine) or placebo. Body composition by DEXA scan, waist circumference, and resting metabolic rate (RMR) were measured at baseline and 8 weeks. Food intake and appetite ratings were measured at baseline and week 2. The second pilot study randomized 20 subjects to two 2-hour RMR tests a week apart after phenylephrine (20 mg) or placebo followed by phenylephrine (20 mg) three times a day for 8 weeks. In the first pilot study, the citrus aurantium group gained 1.13 +/- 0.27 (mean +/- SEM) kg compared with 0.09 +/- 0.28 kg in the placebo group (P < .04). RMR at baseline rose more in the citrus aurantium group, 144.5 +/- 15.7 kcal/24 hours, than the placebo group, 23.8 +/- 28.3 kcal/24 hours (P < .002), but not at 8 weeks. DEXA, waist circumference, food intake, and hunger ratings were not different. In the second pilot study, the phenylephrine group lost 0.8 +/- 3.4 kg in 8 weeks (not significant), and RMR increased more in the phenylephrine group (111.5 +/- 32.6 vs. 37.4 +/- 22.7 kcal/24 hours, P = .02). There were no significant safety issues in either study. Although no toxicity was seen, these pilot studies suggest phenylephrine is not efficacious for weight loss.     

Omega-3 fatty acid supplements for cancer-associated weight loss.

Omega-3 fatty acids have been tested for the treatment of cancer anorexia/weight loss, a syndrome that predicts a poor prognosis among cancer patients with incurable disease. This review focuses on both the preclinical and clinical data of omega-3 fatty acids for treating this syndrome. Overall, the promise of the former does not seem to be borne out completely in the latter. This review includes a discussion of how these data might be interpreted and explained to cancer patients who are striving to cope with this syndrome.     

Nutraceutical supplements for weight loss: a systematic review

Obesity is a global public health issue. Although the etiology of this global epidemic is multifactorial, most sufferers would be delighted to find a relatively effortless way to lose weight. Herbal "weight loss pills" can fit the bill. The authors systematically review the scientific evidence concerning various weight loss agents that are available over the counter or in food stores. The review provides a starting point to make informed choices among nutraceutical agents promoted for weight loss, as well as advice for incorporating healthy alternatives in the diet.     

Dietary supplements

Twenty per cent of the public buy vitamin supplements and a smaller but growing number of dedicated customers buy the products of the health food business. Yet most nutritionists and dietitians say these are quite unnecessary; everything we need can be obtained from the diet. Estimates of nutrient intakes always show a number of individuals well below the acceptable range but with no evidence of any clinical, subclinical or biochemical risk, until recently. Now we have claims that blunderbuss dietary supplementation affects development, behaviour and even IQ. Is this true? Is it applicable to the whole population, to young developing children, to those whose diet is deficient, or will it remain unconfirmed as are the claims for vitamin C and the common cold?     

Dietary energy density and successful weight loss maintenance

Research shows a positive relationship between dietary energy density (ED) and body mass index (BMI), but dietary ED of weight loss maintainers is unknown. This preliminary investigation was a secondary data analysis that compared self-reported dietary ED and food group servings consumed in overweight adults (OW: BMI=27-45kg/m(2)), normal weight adults (NW: BMI=19-24.9 kg/m(2)), and weight loss maintainers (WLM: current BMI=19-24.9kg/m(2) [lost≥10% of maximum body weight and maintained loss for ≥5years]) participating in 2 studies, with data collected from July 2006 to March 2007. Three 24-h phone dietary recalls from 287 participants (OW=97, NW=85, WLM=105) assessed self-reported dietary intake. ED (kcal/g) was calculated by three methods (food+all beverages except water [F+AB], food+caloric beverages [F+CB], and food only [FO]). Differences in self-reported consumption of dietary ED, food group servings, energy, grams of food/beverages, fat, and fiber were assessed using one-way MANCOVA, adjusting for age, sex, and weekly energy expenditure from self-reported physical activity. ED, calculated by all three methods, was significantly lower in WLM than in NW or OW (FO: WLM=1.39±0.45kcal/g; NW=1.60±0.43 kcal/g; OW=1.83±0.42 kcal/g). Self-reported daily servings of vegetables and whole grains consumed were significantly higher in WLM compared to NW and OW (vegetables: WLM=4.9±3.1 servings/day; NW=3.9±2.0 servings/day; OW=3.4±1.7 servings/day; whole grains: WLM=2.2±1.8 servings/day; NW=1.4±1.2 servings/day; OW=1.3±1.3 servings/day). WLM self-reported consuming significantly less energy from fat and more fiber than the other two groups. Self-reported energy intake per day was significantly lower in WLM than OW, and WLM self-reported consuming significantly more grams of food/beverages per day than OW. These preliminary findings suggest that consuming a diet lower in ED, characterized by greater intake of vegetables and whole grains, may aid with weight loss maintenance and should be further tested in prospective randomized controlled trials.     

Dietary and physical activity correlates of long-term weight loss

Covariations in body mass index (BMI), physical activity, macronutrient intake, and the frequency of consumption of specific foods were examined among 82 men and 75 women participating in a behavioral weight loss program over a period of 18 months. Results of repeated measures analyses of covariance showed that BMI change was inversely related to change in physical activity and change in frequency of vegetable consumption. BMI change was positively related to change in calorie intake from fat and change in frequency of consumption of beef, hot dogs, and sweets. Change in fat calories predicted BMI change better than change in total calories. In addition, change in the frequency of consumption of specific foods accounted for a larger percentage of the variance in BMI change than did change in macronutrients (10.4% vs. 5.2%). No differences were found between predictors of weight loss vs. weight maintenance.     

Dietary protein impact on glycemic control during weight loss

Diets with higher protein (1.5 g x kg(-1) x d(-1)) and reduced carbohydrates (120 to 200 g/d) appear to enhance weight loss due to a higher loss of body fat and reduced loss of lean body mass. While studies of prolonged use of moderate protein diets are not available, short-term studies report beneficial effects associated with increased satiety, increased thermogenesis, sparing of muscle protein loss, and enhanced glycemic control. Combined impacts of a moderate protein diet are likely derived from lower carbohydrates resulting in lower postprandial increase in blood glucose and lower insulin response, and higher protein providing increased BCAA leucine levels and gluconeogenic substrates. A key element in the diet appears to be the higher intake of BCAA leucine with unique regulatory actions on muscle protein synthesis, modulation of the insulin signal, and sparing of glucose use by stimulation of the glucose-alanine cycle. This review focuses on the contributions of leucine and the BCAA to regulation of muscle protein synthesis and glycemic control.     

A randomized comparative trial of testosterone and protein supplements for weight loss in HIV+ men

This report presents findings from a randomized trial that compared the efficacy of 1) 400 mg biweekly IM injections of testosterone plus daily “placebo” standard nutritional supplements (containing 8 g of protein per serving), 2) high protein (37 g per serving) supplements and placebo IM injections, and 3) both testosterone and high protein supplements, in the treatment of HIV-related weight loss. Sixty-five HIV+ men with ≤90% of normative body weight or body cell mass entered the study, of whom 54 (83%) completed the 12-week trial. In an intention to treat analysis, the response rates (defined as an increase of at least 5% in the ratio of body cell mass to height) for testosterone (55%), high protein supplements (62%), and both testosterone and protein supplements (73%) were statistically similar (p = NS). Amount of change in body weight, body cell mass, fat free mass and body fat from baseline to Week 12 (as measured by bioelectric impedance analysis), all of which were statistically significant within each group, did not differ across the three groups. Among all completers, the average gain in body weight and body cell mass after 12 weeks was 3.5 kgs and 2.0 kgs, respectively; 77% of the increase in body weight was fat free body mass, compared to 23% fat. These data support the efficacy of both testosterone and high protein supplements as independent treatments for HIV-related weight loss, but do not demonstrate a further advantage of combining the treatments.     

Dietary weight loss decreases serum angiotensin-converting enzyme activity in obese adults

OBJECTIVE: To study the effect of dietary weight loss, postural change, and an oral glucose load on serum angiotensin-converting enzyme (ACE) activity in obese adults. RESEARCH METHODS AND PROCEDURES: Sixteen obese adult men and women with a mean body mass index of 35.7 +/- 4.3 kg/m(2) were studied after 1 week on a maintenance energy lead-in diet and after 5 weeks on an identical but 40% reduced-energy diet provided by the General Clinical Research Center (GCRC). ACE activity was measured spectrophotometrically. Plasma renin activity and serum aldosterone were measured by radioimmunoassay. RESULTS: All subjects lost weight, with a mean decrease in body weight of 7.0 +/- 2.1 kg or 6 +/- 3% of initial body weight (p < 0.00001). Systolic and diastolic blood pressure, supine plasma renin activity, and serum aldosterone levels decreased with weight loss (p < 0.05). Supine ACE activity decreased 23 +/- 12% with weight loss (p < 0.00001). Standing ACE activity, which was significantly higher than supine ACE activity before and after weight loss (p < 0.05), also decreased 18 +/- 17% with weight loss (p = 0.0007). A 75-g oral glucose load had no effect on serum ACE activity over a 3-hour period. DISCUSSION: In obese adults, serum ACE activity declines with modest weight loss, increases with postural change, and is unaffected by an oral glucose load.     

The liberating effect of weight loss supplements on dietary control: A field experiment

ObjectivesTaking weight-loss supplements may create illusion of protection against weight gain and thereby loosen subsequent dietary self-control. The current study examined whether taking weight-loss supplement would increase food intake and further tested whether positive attitudes toward supplements would increase susceptibility to overeating.MethodsParticipants were randomly assigned to take either a known placebo or a purported weight loss supplement (actually, the same placebo). After supplement provision, participants' actual food consumption at a reward buffet lunch was recorded.ResultsCompared with controls, participants receiving a purported weight loss supplement ate more food at the reward buffet. Perceived progress toward the goal of weight reduction mediated the connection between use of weight loss supplements and subsequent food consumption. Participants with more positive attitudes toward weight loss supplements were more susceptible to the liberating effect of taking weight loss supplements on food intake.ConclusionUsing weight loss supplements may produce unintended consequences on dietary self-regulation. The public should pay more attention to the notion of psychological liberation when using weight loss supplements.     

Dietary supplements for body-weight reduction: a systematic review

BACKGROUND: Compliance with conventional weight-management programs is notoriously poor, and a plethora of over-the-counter slimming aids are sold with claims of effectiveness. OBJECTIVE: The objective of the study was to assess the evidence from rigorous clinical trials, systematic reviews, and meta-analyses on the effectiveness of dietary supplements in reducing body weight. DESIGN: The study was a systematic review. Literature searches were conducted on Medline, Embase, Amed, Cinahl, and the Cochrane Library until March 2003. Hand searches of medical journals, the authors' own files, and bibliographies of identified articles were conducted. There were no restrictions regarding the language of publication. The screening of studies, selection, validation, data extraction, and the assessment of methodologic quality were performed independently by the 2 reviewers. To be included, trials were required to be randomized and double-blind. Systematic reviews and meta-analyses of dietary supplements were included if they were based on the results of randomized, double-blind trials. RESULTS: Five systematic reviews and meta-analyses and 25 additional trials were included and reviewed. Data on the following dietary supplements were identified: chitosan, chromium picolinate, Ephedra sinica, Garcinia cambogia, glucomannan, guar gum, hydroxy-methylbutyrate, plantago psyllium, pyruvate, yerba maté, and yohimbe. The reviewed studies provide some encouraging data but no evidence beyond a reasonable doubt that any specific dietary supplement is effective for reducing body weight. The only exceptions are E. sinica- and ephedrine-containing supplements, which have been associated with an increased risk of adverse events. CONCLUSIONS: The evidence for most dietary supplements as aids in reducing body weight is not convincing. None of the reviewed dietary supplements can be recommended for over-the-counter use.     

Prizes for weight loss

A programme of weight loss competitions and associated activities in Tonga, intended to combat obesity and the noncommunicable diseases linked to it, has popular support and the potential to effect significant improvements in health.     

Dietary approaches for weight loss with increased intakes of fruit, vegetables and dairy products

Aim:  To assess the effectiveness of specific advice for increasing fruit, vegetable and dairy intake in free-living men participating in a weight loss study.
Methods:  Subjects were randomised to one of two 12-week weight loss diets, either the WELL with daily targets of four serves of fruit, four serves of vegetables and three serves of dairy or a low fat diet (LF) with general advice to increase fruit and vegetable intake. Three-day food group diaries and a food frequency questionnaire assessed intake.
Results:  Fifty-four overweight/obese male adults completed the study (WELL, n = 27; LF, n = 27; body mass index (mean ± standard deviation), 30.4 ± 2.5 kg/m²; age, 47.7 ± 9.5 years). There was no difference in mean weight change between groups (WELL, −4.8 ± 3.3 kg; LF, −4.6 ± 3.1 kg). Subjects on the WELL diet had greater (mean difference ± standard error) fruit (0.7 ± 0.2 serves/day), vegetable (1.2 ± 0.2 serves/day) and dairy (1.1 ± 0.1 serves/day) intakes than the LF group (measured by the food group diaries) (all P  < 0.01). The WELL group reached the daily target for fruit from week 1 (4.7 ± 1.4 serves/day), vegetables by week 6 (4.1 ± 1.5 serves/day) and for dairy by week 8 (3.0 ± 0.8 serves/day).
Conclusions:  Providing specific dietary targets to men for weight loss appears to promote greater consumption of fruit, vegetable and dairy foods than providing general dietary advice. Meeting dietary targets appears to require different adjustment periods depending on the food type.     

Dietary and physical activity behaviors among adults successful at weight loss maintenance

Background  

There is limited population-based data on behavioral factors found to be important for successful weight loss maintenance among adults.