Isobel Davidson

Intake of polyphenol-rich pomegranate pure juice influences urinary glucocorticoids, blood pressure and homeostasis model assessment of insulin resistance in human volunteers.

Pomegranate juice (PJ; also known as pomegreat pure juice) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective, anti-atherogenic and antihypertensive effects. The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels, blood pressure (BP) and insulin resistance in volunteers at high CVD risk. Subjects (twelve males and sixteen females) participated in a randomised, placebo-controlled cross-over study (BMI: 26·77 (sd 3·36) kg/m2; mean age: 50·4 (sd 6·1) years). Volunteers were assessed at baseline, and at weeks 2 and 4 for anthropometry, BP and pulse wave velocity. Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods, and the cortisol/cortisone ratio was calculated. Fasting blood samples were obtained to assess plasma lipids, glucose, insulin and insulin resistance (homeostasis model assessment of insulin resistance). Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy. Cortisol urinary output was reduced but not significant. However, cortisol/cortisone ratios in urine (P = 0·009) and saliva (P = 0·024) were significantly decreased. Systolic BP decreased from 136·4 (sd 6·3) to 128·9 (sd 5·1) mmHg (P = 0·034), and diastolic BP from 80·3 (sd 4·29) to 75·5 (sd 5·17) mmHg (P = 0·031) after 4 weeks of fruit juice consumption. Pulse wave velocity decreased from 7·5 (sd 0·86) to 7·44 (sd 0·94) m/s (P = 0·035). There was also a significant reduction in fasting plasma insulin from 9·36 (sd 5·8) to 7·53 (sd 4·12) mIU/l (P = 0·025) and of homeostasis model assessment of insulin resistance (from 2·216 (sd 1·43) to 1·82 (sd 1·12), P = 0·028). No significant changes were seen in the placebo arm of the study. These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP, possibly through the inhibition of 11β-hydroxysteroid dehydrogenase type 1 enzyme activity as evidenced by the reduction in the cortisol/cortisone ratio. The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes, obesity and the metabolic syndrome.

A randomised trial of the impact of energy density and texture of a meal on food and energy intake, satiation, satiety, appetite and palatability responses in healthy adults

BACKGROUND & AIMS Texture modified diets may be enriched to optimise the opportunity for individuals to meet their required energy intakes; however there is insufficient evidence supporting this strategy. Thus we sought to investigate the effect of texture and energy density on food (g) and energy intakes (kcal), appetite (satiation and satiety), and palatability in healthy adults. METHODS A single blind within-subjects randomised crossover design, where 33 healthy adults consumed a test meal with either its texture and/or energy density altered, until satiation was reached whilst rating their appetite parameters. Subsequent intakes were recorded in a food diary to determine the effect of the treatments on satiety and identify any evidence of energy compensation. RESULTS Test meal energy intakes (kcal) were significantly higher with energy enrichment of both meals (standard texture; 315 kcal and texture modified; 303 kcal (p = 0.001)) and remained higher over the day for both (260 kcal/d and, 225 kcal/d respectively (p < 0.05)). Area under the curve (AUC) did not differ between meals for hunger, fullness, or desire to eat however palatability was significantly reduced with texture modification. CONCLUSIONS Enriching meals (standard texture and texture modified) is an effective method to increase short term energy intakes in healthy adults over a 24 h period and may have application to optimise energy intakes in a clinical setting.

Prenatal programming of postnatal obesity: fetal nutrition and the regulation of leptin synthesis and secretion before birth

The introduction of the process of nutritional screening into clinical standards has been driven by the increasing awareness of the prevalence of undernutrition in acute and primary care, along with its associated morbidity and mortality. However, the increasing prevalence of obesity in the general population suggests that an increased number of patients admitted to hospital will be obese. Increased morbidity has also been reported in the injured obese patient and may be associated with poor nutritional support. This situation may occur because the profound metabolic disturbances accompanying trauma in this group are not recognised, and subsequent feeding practices are inappropriate. Screening tools currently classify patients by using simple markers of assessment at the whole-body level, such as BMI. Subsequently, patients are identified as at risk only if they are undernourished. Such comparisons would by definition classify injured obese patients as at minimal or no nutritional risk, and they would therefore be less likely to be re-screened. This approach could result in potential increases in morbidity, length of rehabilitation and consequent length of hospital stay. It is likely that the identification of potential risk in obese injured patients goes beyond the measurement of such indices as BMI and percentage weight loss, which are currently utilised by the majority of screening processes.

Morphological and health-related changes associated with a 12-week self-guided exercise programme in overweight adults: a pilot study

Abstract Over 12 weeks, supervised physical activity (PA) interventions have demonstrated improvements in morphological and health parameters, whereas community walking programmes have not. The present study piloted a self-guided programme for promoting PA and reducing sedentary behaviour in overweight individuals and measured its effect on a range of health outcomes. Six male and 16 female sedentary adults aged 48.5 ± 5.5 years with body mass index (BMI) 33.4 ± 6.3 kg m−2 were assessed for anthropometric variables, blood pressure, functional capacity, well-being and fatigue. After an exercise consultation, participants pursued their own activity and monitored PA points weekly. At baseline, mid-point and 12 weeks, eight participants wore activity monitors, and all participants undertook a 5-day food diary to monitor dietary intake. In 17 completers, mass, BMI, sit-to-stand, physical and general fatigue had improved by 6 weeks. By 12 weeks, waist, sagittal abdominal diameter (SAD), diastolic blood pressure, well-being and most fatigue dimensions had also improved. Throughout the intervention, PA was stable, energy intake and lying time decreased and standing time increased; thus, changes in both energy intake and expenditure explain the health-related outcomes. Observed changes in function, fatigue and quality of life are consistent with visceral fat loss and can occur at levels of weight loss which may not be considered clinically significant.

Strategies to improve ingestive behaviour with reference to critical illness

The complex interplay between neural and endocrine responses following food intake regulates ingestive behaviour and ultimately determines subsequent energy intake. These processes include cognitive, gastrointestinal-derived and metabolic mechanisms. Such physiological responses to the ingestion of food initiate short- to medium-term inhibition of intake (satiety). However, in clinical states in which systemic inflammation is evident there is a more profound satiety response and a clear absence of motivation to eat that is evident as loss of appetite. These negative influences on energy intake can contribute to poor nutritional status, and consequently poor physical function, and impact on rehabilitation and recovery. Cytokine mediators of the inflammatory response directly influence feeding behaviour at the hypothalamic nuclei and may explain the lack of motivation and desire for food. However, additional detrimental effects on appetite are brought about because of alterations in intermediary metabolism present in inflammation-induced catabolism. This process forms part of the host response to inflammation and may explain symptoms, such as early satiety, frequently reported in many patient groups. In clinical states, and cancer in particular, pharmacological strategies have been employed to ameliorate the inflammatory response in an attempt to improve energy intake. Some success of this approach has been reported following administration of substrates such as EPA. Novel strategies to improve intake through administration of anti-cytokine drugs such as thalidomide may also be of benefit. However, drugs that oppose the actions of neurotransmitter pathways involved in central induction of satiety, such as 5-hydroxytryptamine, have failed to improve intake but appear to enhance enjoyment of food. Such findings indicate that therapeutic nutritional targets can only be achieved where novel pharmacological therapies can be supported by more innovative and integrated dietary management strategies. Many of these strategies remain to be elucidated.

Prevalence of sarcopenia in a Scottish cohort with chronic kidney disease (CKD) receiving haemodialysis and its association with clinical parameters

The presence of chronic kidney disease (CKD) has been suggested to elicit early onset reductions in lean body mass leading to disease related sarcopenia and poor functional performance. We investigated the prevalence of sarcopenia in a Scottish cohort receiving long term (>6 months) haemodialysis and its association with age, dialysis vintage, comorbidity and inflammation. The diagnosis of sarcopenia was based on the European consensus definition and diagnosis. Handgrip as a marker of muscle strength was measured pre dialysis. Height and weight were measured post dialysis for the calculation of body mass index (BMI). Calf circumference (CC) and mid arm muscle circumference (MAMC) were measured post dialysis as anthropometric estimates of muscle mass. Dual frequency bioelectrical impedance analysis (DFBIA) was also measured post dialysis to derive skeletal muscle index (SMI). Functional performance was assessed using the 6-minute walk test and number of sit-to-stand transitions performed in 1 minute. Comorbidity scores were determined using the Charlson co-morbidity index scoring system, monthly high sensitivity C-reactive protein (hsCRP) results were used to determine the presence of inflammation and dialysis vintage was calculated from the first date renal replacement therapy was initiated. Sixty-four patients were recruited 39 male & 25 female with a mean age of 54 years 16 (SD) and BMI of 27·6 Kg/m 6·3 (SD), mean hsCRP was 11·6 mgL 5·1 (SD), mean dialysis vintage was 75·0 months 84·8 (SD). 43·8% were identified as sarcopenic, with 26·6% presenting with severe sarcopenia. Sarcopenic obesity was present in 20·3%. Those with sarcopenia performed fewer sit-to-stand transitions and walked less distance in 6 minutes than those without sarcopenia. Whilst a significant difference in SMI was observed between those with and without sarcopenia, no difference in calf circumference or mid arm muscle circumference was evident.

The investigation of the effects of food texture and energy density on appetite and food intakes at a single eating occasion in older adults: A pilot study

dsignificantly different vs. meal 2 p = 0.01. It appears that texture modification results in reduced food intake of both a standard and an energy enriched meal at a single eating occasion. Energy intake at a single eating occasion may be increased by energy enrichment in both standard and texture modified meals, but whether this results in increased daily energy and nutrient intakes remains to be determined. This and further investigation into the impact of the aesthetic attributes of texture modified and energy enriched meals on food and energy intakes is required to inform optimisation of food and fluid provision.