The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults

CONTEXT: Chitosan, a deacetylated chitin, is a widely available dietary supplement purported to decrease body weight and serum lipids through gastrointestinal fat binding. Although evaluated in a number of trials, its efficacy remains in dispute. OBJECTIVE: To evaluate the efficacy of chitosan for weight loss in overweight and obese adults. DESIGN AND SETTING: A 24-week randomised, double-blind, placebo-controlled trial, conducted at the University of Auckland between November 2001 and December 2002. PARTICIPANTS: A total of 250 participants (82% women; mean (s.d.) body mass index, 35.5 (5.1) kg/m(2); mean age, 48 (12) y). INTERVENTIONS: Participants were randomly assigned to receive 3 g chitosan/day (n = 125) or placebo (n = 125). All participants received standardised dietary and lifestyle advice for weight loss. Adherence was monitored by capsule counts. MAIN OUTCOME MEASURES: The primary outcome measure was change in body weight. Secondary outcomes included changes in body mass index, waist circumference, body fat percentage, blood pressure, serum lipids, plasma glucose, fat-soluble vitamins, faecal fat, and health-related quality of life. RESULTS: In an intention-to-treat analysis with the last observation carried forward, the chitosan group lost more body weight than the placebo group (mean (s.e.), -0.4 (0.2) kg (0.4% loss) vs +0.2 (0.2) kg (0.2% gain), P = 0.03) during the 24-week intervention, but effects were small. Similar small changes occurred in circulating total and LDL cholesterol, and glucose (P < 0.01). There were no significant differences between groups for any of the other measured outcomes. CONCLUSION: In this 24-week trial, chitosan treatment did not result in a clinically significant loss of body weight compared with placebo.

Bone loss in Crohn's disease: Exercise as a potential countermeasure

Crohn's disease (CD) is associated with a number of secondary conditions including osteoporosis, which increases the risk of bone fracture. The cause of metabolic bone disease in this Population is believed to be multifactorial and may include the disease itself and associated inflammation, high-close corticosteroid use, weight loss and malabsorption, a lack of exercise and physical activity, and all underlying genetic predisposition to bone loss. Reduced bone mineral density has been reported in between 5% to 80% of CD sufferers, although it is generally believed that approximately 40% of patients suffer from osteopenia and 15% from osteoporosis. Recent studies Suggest a small but significantly increased risk of fracture compared with healthy controls and, perhaps, sufferers of other gastrointestinal disorders Such as ulcerative colitis. The role of physical activity and exercise in the prevention and treatment of CD-related bone loss has received little attention, despite the benefits of specific exercises being well documented in healthy populations. This article reviews the prevalence of and risk factors for low bone mass in CD patients and examines various treatments for osteoporosis in these patients, with a particular focus on physical activity.

Weight gained in two years by a population of mid-aged women: how much is too much?

Objective: To establish the prevalence of weight change in mid-aged women over a 2-year period, and to assess the relationship between weight change and physical and mental well-being (SF36) in order to begin debate about the need for quantified standards of weight gain. Design: Prospective study of weight change and well-being over a 2-year period among mid-aged women participating in a large national survey. Subjects: Seven thousand two hundred and seventy women without surgical menopause aged between 45 and 50 years (termed mid-aged), enrolled in the Australian Longitudinal Study on Women's Health. Measurements: Weight change (self-reported weight at two time points) and physical and mental well-being (SF-36) explored using linear regression, while adjusting for potential confounders. Results: Only half the women maintained their weight within 2.25 kg, and one-third gained more than this amount in a 2-year period. While weight gain (>= 2.25 kg) was negatively associated with physical well-being, both weight loss and weight gain were associated with poorer mental well-being. Conclusion: This is the first prospective study using a large, population-based cohort to demonstrate that small changes in weight are associated with changes in well-being in mid-aged Australian women. It provides further evidence of the need for public health messages to specify the actual amount that constitutes weight gain, but further research is needed to establish these standards for the entire population.

Conditional deletion of hypothalamic Y2 receptors reverts gonadectomy-induced bone loss in adult mice

Reduction in levels of sex hormones at menopause in women is associated with two common, major outcomes, the accumulation of white adipose tissue, and the progressive loss of bone because of excess osteoclastic bone resorption exceeding osteoblastic bone formation. Current antiresorptive therapies can reduce osteoclastic activity but have only limited capacity to stimulate osteoblastic bone formation and restore lost skeletal mass. Likewise, the availability of effective pharmacological weight loss treatments is currently limited. Here we demonstrate that conditional deletion of hypothalamic neuropeptide Y2 receptors can prevent ongoing bone loss in sex hormone-deficient adult male and female mice. This benefit is attributable solely to activation of an anabolic osteoblastic bone formation response that counterbalances persistent elevation of bone resorption, suggesting the Y2-mediated anabolic pathway to be independent of sex hormones. Furthermore, the increase in fat mass that typically occurs after ovariectomy is prevented by germ line deletion of Y2 receptors, whereas in male mice body weight and fat mass were consistently lower than wild-type regardless of sex hormone status. Therefore, this study indicates a role for Y2 receptors in the accumulation of adipose tissue in the hypogonadal state and demonstrates that hypothalamic Y2 receptors constitutively restrain osteoblastic activity even in the absence of sex hormones. The increase in bone formation after release of this tonic inhibition suggests a promising new avenue for osteoporosis treatment.

Increased expression of phosphorylated forms of RNA-dependent protein kinase and eukaryotic initiation factor 2 alpha may signal skeletal muscle atrophy in weight-losing cancer patients

Previous studies suggest that the activation (autophosphorylation) of dsRNA-dependent protein kinase (PKR) can stimulate protein degradation, and depress protein synthesis in skeletal muscle through phosphorylation of the translation initiation factor 2 (eIF2) on the alpha-subunit. To understand whether these mediators are important in muscle wasting in cancer patients, levels of the phospho forms of PKR and eIF2alpha have been determined in rectus abdominus muscle of weight losing patients with oesophago-gastric cancer, in comparison with healthy controls. Levels of both phospho PKR and phospho eIF2alpha were significantly enhanced in muscle of cancer patients with weight loss irrespective of the amount and there was a linear relationship between phosphorylation of PKR and phosphorylation of eIF2alpha (correlation coefficient 0.76, P=0.005). This suggests that phosphorylation of PKR led to phosphorylation of eIF2alpha. Myosin levels decreased as the weight loss increased, and there was a linear relationship between myosin expression and the extent of phosphorylation of eIF2alpha (correlation coefficient 0.77, P=0.004). These results suggest that phosphorylation of PKR may be an important initiator of muscle wasting in cancer patients.

Attenuation of proteasome-induced proteolysis in skeletal muscle by beta-hydroxy-beta-methylbutyrate in cancer-induced muscle loss

Loss of skeletal muscle is an important determinant of survival in patients with cancer-induced weight loss. The effect of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) on the reduction of body weight loss and protein degradation in the MAC16 model of cancer-induced weight loss has been compared with that of eicosapentaenoic acid (EPA), a recognized inhibitor of protein degradation. HMB was found to attenuate the development of weight loss at a dose greater than 0.125 g/kg accompanied by a small reduction in tumor growth rate. When EPA was used at a suboptimal dose level (0.6 g/kg) the combination with HMB seemed to enhance the anticachectic effect. Both treatments caused an increase in the wet weight of soleus muscle and a reduction in protein degradation, although there did not seem to be a synergistic effect of the combination. Proteasome activity, determined by the "chymotrypsin-like" enzyme activity, was attenuated by both HMB and EPA. Protein expression of the 20S alpha or beta subunits was reduced by at least 50%, as were the ATPase subunits MSS1 and p42 of the 19S proteasome regulatory subunit. This was accompanied by a reduction in the expression of E2(14k) ubiquitin-conjugating enzyme. The combination of EPA and HMB was at least as effective or more effective than either treatment alone. Attenuation of proteasome expression was reflected as a reduction in protein degradation in gastrocnemius muscle of cachectic mice treated with HMB. In addition, HMB produced a significant stimulation of protein synthesis in skeletal muscle. These results suggest that HMB preserves lean body mass and attenuates protein degradation through down-regulation of the increased expression of key regulatory components of the ubiquitin-proteasome proteolytic pathway, together with stimulation of protein synthesis.

Expression of the ubiquitin-proteasome pathway and muscle loss in experimental cancer cachexia

Muscle protein degradation is thought to play a major role in muscle atrophy in cancer cachexia. To investigate the importance of the ubiquitin-proteasome pathway, which has been suggested to be the main degradative pathway mediating progressive protein loss in cachexia, the expression of mRNA for proteasome subunits C2 and C5 as well as the ubiquitin-conjugating enzyme, E2(14k), has been determined in gastrocnemius and pectoral muscles of mice bearing the MAC16 adenocarcinoma, using competitive quantitative reverse transcriptase polymerase chain reaction. Protein levels of proteasome subunits and E2(14k) were determined by immunoblotting, to ensure changes in mRNA were reflected in changes in protein expression. Muscle weights correlated linearly with weight loss during the course of the study. There was a good correlation between expression of C2 and E2(14k) mRNA and protein levels in gastrocnemius muscle with increases of 6-8-fold for C2 and two-fold for E2(14k) between 12 and 20% weight loss, followed by a decrease in expression at weight losses of 25-27%, although loss of muscle protein continued. In contrast, expression of C5 mRNA only increased two-fold and was elevated similarly at all weight losses between 7.5 and 27%. Both proteasome functional activity, and proteasome-specific tyrosine release as a measure of total protein degradation was also maximal at 18-20% weight loss and decreased at higher weight loss. Proteasome expression in pectoral muscle followed a different pattern with increases in C2 and C5 and E2(14k) mRNA only being seen at weight losses above 17%, although muscle loss increased progressively with increasing weight loss. These results suggest that activation of the ubiquitin-proteasome pathway plays a major role in protein loss in gastrocnemius muscle, up to 20% weight loss, but that other factors such as depression in protein synthesis may play a more important role at higher weight loss. © 2005 Cancer Research.

Evaluation of the Heart of Birmingham teaching Primary Care Trust (HoBtPCT): My Choice Weight Management Programme:report commissioned by Heart of Birmingham teaching Primary Care Trust

This report details an evaluation of the My Choice Weight Management Programme undertaken by a research team from the School of Pharmacy at Aston University. The My Choice Weight Management Programme is delivered through community pharmacies and general practitioners (GPs) contracted to provide services by the Heart of Birmingham teaching Primary Care Trust. It is designed to support individuals who are ‘ready to change’ by enabling the individual to work with a trained healthcare worker (for example, a healthcare assistant, practice nurse or pharmacy assistant) to develop a care plan designed to enable the individual to lose 5-10% of their current weight. The Programme aims to reduce adult obesity levels; improve access to overweight and obesity management services in primary care; improve diet and nutrition; promote healthy weight and increased levels of physical activity in overweight or obese patients; and support patients to make lifestyle changes to enable them to lose weight. The Programme is available for obese patients over 18 years old who have a Body Mass Index (BMI) greater than 30 kg/m2 (greater than 25 kg/m2 in Asian patients) or greater than 28 kg/m2 (greater than 23.5 kg/m2 in Asian patients) in patients with co-morbidities (diabetes, high blood pressure, cardiovascular disease). Each participant attends weekly consultations over a twelve session period (the final iteration of these weekly sessions is referred to as ‘session twelve’ in this report). They are then offered up to three follow up appointments for up to six months at two monthly intervals (the final of these follow ups, taking place at approximately nine months post recruitment, is referred to as ‘session fifteen’ in this report). A review of the literature highlights the dearth of published research on the effectiveness of primary care- or community-based weight management interventions. This report may help to address this knowledge deficit. A total of 451 individuals were recruited on to the My Choice Weight Management Programme. More participants were recruited at GP surgeries (n=268) than at community pharmacies (n=183). In total, 204 participants (GP n=102; pharmacy n=102) attended session twelve and 82 participants (GP n=22; pharmacy 60) attended session fifteen. The unique demographic characteristics of My Choice Weight Management Programme participants – participants were recruited from areas with high levels of socioeconomic deprivation and over four-fifths of participants were from Black and Minority Ethnic groups; populations which are traditionally underserved by healthcare interventions – make the achievements of the Programme particularly notable. The mean weight loss at session 12 was 3.8 kg (equivalent to a reduction of 4.0% of initial weight) among GP surgery participants and 2.4 kg (2.8%) among pharmacy participants. At session 15 mean weight loss was 2.3 kg (2.2%) among GP surgery participants and 3.4 kg (4.0%) among pharmacy participants. The My Choice Weight Management Programme improved the general health status of participants between recruitment and session twelve as measured by the validated SF-12 questionnaire. While cost data is presented in this report, it is unclear which provider type delivered the Programme more cost-effectively. Attendance rates on the Programme were consistently better among pharmacy participants than among GP participants. The opinions of programme participants (both those who attended regularly and those who failed to attend as expected) and programme providers were explored via semi-structured interviews and, in the case of the participants, a selfcompletion postal questionnaire. These data suggest that the Programme was almost uniformly popular with both the deliverers of the Programme and participants on the Programme with 83% of questionnaire respondents indicating that they would be happy to recommend the Programme to other people looking to lose weight. Our recommendations, based on the evidence provided in this report, include: a. Any consideration of an extension to the study also giving comparable consideration to an extension of the Programme evaluation. The feasibility of assigning participants to a pharmacy provider or a GP provider via a central allocation system should also be examined. This would address imbalances in participant recruitment levels between provider type and allow for more accurate comparison of the effectiveness in the delivery of the Programme between GP surgeries and community pharmacies by increasing the homogeneity of participants at each type of site and increasing the number of Programme participants overall. b. Widespread dissemination of the findings from this review of the My Choice Weight Management Project should be undertaken through a variety of channels. c. Consideration of the inclusion of the following key aspects of the My Choice Weight Management Project in any extension to the Programme: i. The provision of training to staff in GP surgeries and community pharmacies responsible for delivery of the Programme prior to patient recruitment. ii. Maintaining the level of healthcare staff input to the Programme. iii. The regular schedule of appointments with Programme participants. iv. The provision of an increased variety of printed material. d. A simplification of the data collection method used by the Programme commissioners at the individual Programme delivery sites.

A comparison of the provision of the My Choice Weight Management Programme via general practitioner practices and community pharmacies in the United Kingdom

This study aimed to assess the effectiveness of a novel, community-based weight management programme delivered through general practitioner (GP) practices and community pharmacies in one city in the United Kingdom. This study used a non-randomized, retrospective, observational comparison of clinical data collected by participating GP practices and community pharmacies. Subjects were 451 overweight or obese men and women resident in areas of high socioeconomic deprivation (82% from black and minority ethnic groups, 86% women, mean age: 41.1 years, mean body mass index [BMI]: 34.5 kg m−2). Weight, waist circumference and BMI at baseline, after 12 weeks and after 9 months were measured. Costs of delivery were also analysed. Sixty-four per cent of participants lost weight after the first 12 weeks of the My Choice Weight Management Programme. There was considerable dropout. Mean percentage weight loss (last observation carried forward) was 1.9% at 12 weeks and 1.9% at final follow-up (9 months). There was no significant difference in weight loss between participants attending GP practices and those attending pharmacies at both 12 weeks and at final follow-up. Costs per participant were higher via community pharmacy which was attributable to better attendance at sessions among community pharmacy participants than among GP participants. The My Choice Weight Management Programme produced modest reductions in weight at 12 weeks and 9 months. Such programmes may not be sufficient to tackle the obesity epidemic.

Description and preliminary results from a structured specialist behavioural weight management group intervention:Specialist Lifestyle Management (SLiM) programme

Background -  Specialist Lifestyle Management (SLiM) is a structured patient education and self-management group weight management programme. Each session is run monthly over a 6-month period providing a less intensive long-term approach. The groups are patient-centred incorporating educational, motivational, behavioural and cognitive elements. The theoretical background, programme structure and preliminary results of SLiM are presented. Subjects/methods - The study was a pragmatic service evaluation of obese patients with a body mass index (BMI) ≥35 kg/m2 with comorbidity or ≥40 kg/m2 without comorbidity referred to a specialist weight management service in the West Midlands, UK. 828 patients were enrolled within SLiM over a 48-month period. Trained facilitators delivered the programme. Preliminary anonymised data were analysed using the intention-to-treat principle. The primary outcome measure was weight loss at 3 and 6 months with comparisons between completers and non-completers performed. The last observation carried forward was used for missing data. Results - Of the 828 enrolled within SLiM, 464 completed the programme (56%). The mean baseline weight was 135 kg (BMI=49.1 kg/m2) with 87.2% of patients having a BMI≥40 kg/m2 and 12.4% with BMI≥60 kg/m2. The mean weight change of all patients enrolled was −4.1 kg (95% CI −3.6 to −4.6 kg, p=0.0001) at the end of SLiM, with completers (n=464) achieving −5.5 kg (95% CI −4.2 to −6.2 kg, p=0.0001) and non-completers achieving −2.3 kg (p=0.0001). The majority (78.6%) who attended the 6-month programme achieved weight loss with 32.3% achieving a ≥5% weight loss. Conclusions - The SLiM programme is an effective group intervention for the management of severe and complex obesity.

Impact of a cognitive-behavioral weight control program on body weight, diet quality, and smoking cessation in weight-concerned female smokers

Many people use smoking as a weight control mechanism and do not want to quit because they fear weight gain. These weight-concerned smokers tend to be female, are significantly less likely to stop smoking, are less likely to join smoking cessation programs, and will relapse more often than smokers who are not weight-concerned. Research suggests that a woman’s confidence in her ability to control her weight after quitting relates positively with her intention to quit smoking. Likewise, success in smoking cessation has been associated with increased self-efficacy for weight control. It has been shown that success in changing one negative health behavior may trigger success in changing another, causing a synergistic effect. Recently research has focused on interventions for weight-concerned smokers who are ready to quit smoking. The present study investigated the effect of a cognitive based weight control program on self-efficacy for weight control and the effect on smoking behavior for a group of female weight concerned smokers. Two hundred and sixteen subjects who wanted to lose weight but who were not ready to quit smoking were recruited to participate in a 12-week, cognitive-behavioral weight control program consisting of twelve one-hour sessions. Subjects were randomly assigned to either (1) the weight-control program (intervention group), or (2) the control group. Results of this study demonstrated that subjects in the intervention group increased self-efficacy for weight control, which was associated with improved healthy eating index scores, weight loss, increased self-efficacy for quitting smoking, a decrease in number of cigarettes smoked and triggered positive movement in stage of change towards smoking cessation compared to the control subjects. For these subjects, positive changes in self-efficacy for one behavior (weight control) appeared to have a positive effect on their readiness to change another health behavior (smoking cessation). Further study of the psychological variables that influence weight-concerned female smokers’ decisions to initiate changes in these behaviors and their ability to maintain those changes are warranted.

Impact of a comprehensive nutrition and lifestyle education intervention on body weight and health-related outcomes in morbidly-obese Hispanic-Americans following laparoscopic Roux-en-Y gastric bypass

As morbid obesity increasingly affects Hispanic-Americans, the incidence of Roux-en-Y gastric bypass procedures (RYGB) among this population rises. Prospective research on the impact of postoperative educational interventions focused on Hispanic- Americans is needed to prevent premature weight loss plateau, weight regain, nutritional deficiencies, and relapse of obesity-related comorbidities. This randomized-controlled study evaluated the impact of a comprehensive nutrition and lifestyle education intervention (6 biweekly postoperative sessions that incorporated motivational strategies for behavioral change) as compared to a non-comprehensive approach (printed guidelines for healthy lifestyle). The variables to consider are body weight, obesity-related comorbidities (depression, diabetes, dyslipidemia, and others), nutrient status, physical activity, and eating habits in 144 morbidly-obese adult Hispanic-Americans 6 to 12 months following RYGB. Patients were randomly assigned to either the comprehensive intervention (n=72) or the comparison group (n=72). Participants (mean age 44.5 ± 13.5 years) were mainly Cuban-born females (83.3%). Intervention sessions attendance was 64%. At 12 months, both groups lost weight significantly, but those in the comprehensive intervention experienced greater excess weight loss than those in the comparison group (80% vs. 64% from preoperative excess weight, P<.001). Intervention participants were significantly more involved in physical activity (+ 14 min/week vs. – 4 min/week), had decreased depression, joint illness, and required less medication for comorbidities than comparison participants. Additionally, those in the comprehensive intervention had sustained supplement intake experiencing less folate deficiency (P=.014). The non-comprehensive intervention group significantly decreased their protein and supplement intake compared to the intervention group. Patients in the comprehensive intervention had significantly better eating habits reflected by fewer episodes of dumping syndrome, constipation, and night eating, than those in the comparison group who reported greater eating in response to negative emotions (P=.003). These findings support the importance of a comprehensive educational approach to achieve more effective weight reduction and health-related outcomes to prevent relapse of obesity-related comorbidities and nutritional deficiencies in Hispanic-Americans 6 to 12 months following RYGB.

(Table 1) Foraminifera weight, size index and CO3 concentrations of core top sediments

Down water column traverses of core top weights for three planktonic species confirm Lohmann's (1995) relationship between foraminifera shell weight loss and bottom water carbonate ion content. However, they also suggest that the initial shell thickness varies with growth habitat and that the offset between bottom water and pore water carbonate ion concentration varies even on small space scales.