Sandra Drummond

The effect of including a conventional snack (cereal bar) and a nonconventional snack (almonds) on hunger, eating frequency, dietary intake and body weight

BACKGROUND With the increasing prevalence of being overweight and obesity, dietary strategies to curb hunger levels and increase satiety at lower energy intakes are sought. The frequency of eating and type of snack may influence total energy intake. The present study aimed to assess the impact of providing either a conventional snack (cereal bar) or a nonconventional snack (almonds) on eating frequency, hunger rating, dietary intake, body weight and blood lipids. METHODS Forty-five healthy men (aged 25-50 years, body mass index = 25-35 kg m(-2)) were recruited and allocated to a control, cereal bar or almond snack group. Two packets of cereal bars and almonds were introduced for 12 weeks to the cereal bar group and the almond snack group, respectively. Dietary intakes and eating frequency were assessed by 4-day unweighed diet diaries; visual analogue scales were used to assess hunger ratings; and fasting blood parameters (i.e. glucose, insulin, total cholesterol, triglycerides, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol) were measured at baseline, 6 and 12 weeks. In addition, anthropometric measures (height, weight, skinfold thickness, waist and hip circumference) were measured at baseline, 6 and 12 weeks. RESULTS The present study found no significant change in the eating frequency within groups at 12 weeks. However, the almond snack group had a significantly higher eating frequency than the control group (P < or = 0.05) and cereal bar group (P < or = 0.01). This did not result in higher energy intake, body weight or percentage body fat in the almond snack group. CONCLUSION The present study demonstrated that snacking on almonds, in comparison to cereal bars, promoted a higher eating frequency, but not a higher energy intake. Advice to snack on either almonds or cereal bars did not result in weight gain, suggesting that energy compensation took place.

Dark chocolate: an obesity paradox or a culprit for weight gain?

Obesity remains a major public health challenge, and its prevalence is dramatically increasing. Diet and exercise are typically recommended to prevent and manage obesity; however, the results are often conflicting. Polyphenols, a class of phytochemicals that have been shown to reduce the risk factors for diabetes type II and cardiovascular diseases, are recently suggested as complementary agents in the management of obesity through several mechanisms such as decreasing fat absorption and/or fat synthesis. Dark chocolate, a high source of polyphenols, and flavanols in particular, has lately received attention for its possible role in modulating obesity because of its potential effect on fat and carbohydrate metabolism, as well as on satiety. This outcome was investigated in animal models of obesity, cell cultures and few human observational and clinical studies. The research undertaken to date has shown promising results, with the possible implication of cocoa/dark chocolate in the modulation of obesity and body weight through several mechanisms including decreasing the expression of genes involved in fatty acid synthesis, reducing the digestion and absorption of fats and carbohydrates and increasing satiety. Copyright

Effects of advice on dietary intake and/or physical activity on body composition, blood lipids and insulin resistance following a low-fat, sucrose-containing, high-carbohydrate, energy-restricted diet

Aim To determine the effect of dietary advice in conjunction with advice to increase physical activity on the body composition, blood lipid and insulin profiles in overweight women. Design A 12-week randomized controlled intervention study. Subjects were assigned to one of four groups: (1) no advice, (2) low-fat, high-carbohydrate (including sucrose) energy-reduced diet, (3) 60 min/day brisk walking, and (4) diet and activity advice as previous. Subjects Sixty-nine overweight women (mean age 41 years). Measurements Dietary compliance was assessed by 4-day diet diaries. Activity levels were assessed by Caltrac™ accelerator monitors. Anthropometric changes were recorded at baseline, 6 and 12 weeks. Fasting blood samples measuring glucose, insulin, and blood lipids were recorded at baseline and 12 weeks. Results Group 4 achieved greatest weight loss of 4.2 kg and greatest reduction in waist circumference of 6.5 cm. Groups 2 and 4 decreased the percentage energy from fat by 5.2%. Group 3 increased the percentage energy from fat by 4.0%. Group 4 significantly reduced total cholesterol by 0.45 mmol/l and low-density lipoprotein-cholesterol by 0.53 mmol/l. Conclusion A low-fat, high-carbohydrate, sucrose-containing diet combined with increased physical exercise resulted in greater health benefits than diet or physical activity advice alone.

Weight loss on an energy-restricted, low-fat, sugar-containing diet in overweight sedentary men

With the increasing prevalence of obesity in the United Kingdom, the search for an effective weight reducing diet is a priority in helping to reverse this trend. A 12-week dietary intervention study was carried out to test the effectiveness of an energy-restricted, low-fat, sugar-containing diet on weight loss in sedentary overweight men. The study also aimed to assess eating behaviour, to measure change in attitude towards sugar-containing foods and to measure the impact of the study on perceived quality of life. Subjects were recruited from three UK cities; Edinburgh, Birmingham and London. Seventy-six men, aged between 25 and 60 years, completed the study. Baseline diets were assessed by a 7-day diet diary. Compliance to the subsequent dietary advice was measured on four occasions post intervention, by 4-day diaries. Measures of body weight status were also monitored. Eating behaviour, attitudes towards sugar-containing foods and quality of life were assessed by questionnaire. Significant reductions in body weight (5.2%), body fat (11.2%) and waist:hip ratio (3%) were observed following reported dietary changes that included a reduction in reported energy intake of 3.2 MJ/day (770 kcal/day), a reduction in the percent energy from fat (from 38.1% to 26.2%), an increase in the percent energy from total carbohydrate (from 44.4% to 54%) and from protein (from 17.3% to 20.6%). Subjects scored relatively highly for dietary restraint and emotional eating, and were strongly influenced by external eating cues. On completion of the 12-week study, subjects had a more positive attitude towards sugar-containing foods and perceived an improved quality of life. It is concluded, therefore, that including sugar-containing foods in a weight-reducing diet may be an effective strategy to achieve a palatable, low-fat, high-carbohydrate diet, which promotes weight loss in overweight individuals.

Polyphenols and Their Role in Obesity Management: A Systematic Review of Randomized Clinical Trials

Polyphenols have been suggested to reduce body weight and modify body composition through different mechanisms. These effects have been extensively studied in animals and in vitro and to a lesser extent in humans. The aim of this review is to consider the association between polyphenols and body weight status by focusing on human intervention studies. We conducted a systematic literature search in MEDLINE (via EBSCOhost), ProQuest CENTRAL, and Cochrane CENTRAL without time restrictions. Randomized controlled trials assessing the effect of polyphenols on weight and/or body composition in the overweight and/or obese population were included. Nineteen studies met our inclusion criteria. Results suggest that further research is required before supporting a potential role of polyphenols in reducing weight in overweight and obese individuals (nine studies showed a significant decrease in weight by a mean of 1.47 ± 0.58 kg). Nevertheless, several studies indicated that polyphenols might be effective in preventing small increases in weight during periods of overfeeding rather than reducing weight as such. The outcomes noted do not yet support polyphenol supplementation as a complementary approach in weight loss diets. Further larger trials with a duration of 12 months or more are needed to elucidate the effect of polyphenols on body weight status. Copyright

The need to standardize ad libitum eating protocols in dietary fibre appetite research.

Since more than 1.9 billion adults worldwide are overweight, of which 600 million are obese,1 it is of vital importance to identify treatment strategies to help overweight and obese patients to lose weight and to improve long-term health. From a nutrition perspective, research has focussed on increasing the satiating power of the diet so that individuals feel full with fewer calories. A potentially effective class of functional foods, modulating appetite and food intake in such ways, is dietary fibre. However, although emerging evidence highlights the positive effects of dietary fibre on appetite and body weight, the methodological approaches are not always consistent and give rise to many uncertainties.

Effects of oat β-glucan consumption at breakfast on ad libitum eating, appetite, glycemia, insulinemia and GLP-1 concentrations in healthy subjects

There is evidence that oat β-glucan lowers appetite and ad libitum eating; however, not all studies are consistent, and the underpinning mechanisms are not entirely understood. We investigated the effects of 4 g high molecular weight (MW) oat β-glucan on ad libitum eating, subjective appetite, glycemia, insulinemia and plasma GLP-1 responses in 33 normal-weight subjects (22 female/11 male, mean age (y): 26.9 ± 1.0, BMI (kg/m2): 23.5 ± 0.4). The study followed a randomised double-blind, cross-over design with subjects fed two test breakfasts with and without oat β-glucan followed by an ad libitum test meal on two different days. Blood samples and ratings for subjective appetite were collected postprandially at regular time intervals. Oat β-glucan increased feelings of fullness (p = 0.048) and satiety (p = 0.034), but did not affect energy and amount eaten at the ad libitum test meal. There was a treatment by time interaction for plasma GLP-1, plasma insulin and blood glucose. GLP-1 was significantly reduced at 90 min (p = 0.021), blood glucose at 30 min (p = 0.008) and plasma insulin at 30 and 60 min (p = 0.002 and 0.017, respectively) following the oat β-glucan breakfast when compared with the control breakfast. Four grams of high MW oat β-glucan lowers appetite but not ad libitum eating and beneficially modulates postprandial glycaemia, it does however, not increase plasma GLP-1 secretion.

Comparison of three school-based intervention strategies to increase starch consumption in adolescent Scottish boys

The aim of the present study was to compare three 4-week school-based interventions to increase starch intake in adolescent Scottish boys. A randomised controlled intervention study was employed and seventy-six boys (aged 12‐13 years) from four local authority schools within North Lanarkshire were randomly recruited to one of four groups: A, control (received no specific advice); B, provided with an education package on starch that was designed to be fun and educate the subjects on the benefits of eating starchy foods; C, provided with starchy snacks (Rice Krispies, Cornflakes and Nutrigrain bars (Kellogg’s Manchester, UK) and Twiglets (United Biscuits, Aintree, Merseyside, UK); D, provided with both the education package and the snacks. Ethical approval for the study was granted by Queen Margaret University College Ethical Committee and The Research Ethics Committee of Lanarkshire Health Board. Dietary intakes were estimated using a 3 d diet diary at baseline and at 4 weeks post intervention. Full instructions for completion of the diary were given at the start of the dietary recording period by the researcher. Specific questions on starchy food consumption were included to ensure that all starchy foods consumed were recorded. Energy and nutrient intakes were assessed using CompeatPro version 5.0 (Nutrition Systems, Banbury, Oxon, UK). Statistical analyses were performed using SPSS version 11.5 (SPSS Inc, Chicago, IL, USA). Paired-sample t tests were used to compare data at baseline and at 4 weeks post intervention. After 4 weeks group C showed an increased % energy from starch (from 29 to 34; P < 0.001) and a decreased % energy from total sugar (from 24 to 19.7; P < 0.05) with no significant change in total carbohydrate. Group D showed an increased % energy from starch (from 27 to 33; P < 0.005) and total carbohydrate (from 49.8 to 54.3; P < 0.01). Group D also showed a decreased % energy from fat (from 39 to 35; P < 0.005). It was concluded from the study that a simple intervention package, including dietary education and provision of snacks high in starch, resulted in beneficial dietary changes in adolescent boys. However, longer-term studies are required to assess the sustainability of these dietary changes.