Duane Mellor

Diabetes UK evidence-based nutrition guidelines for the prevention and management of diabetes

A summary of the latest evidence‐based nutrition guidelines for the prevention and management of diabetes is presented. These guidelines are based on existing recommendations last published in 2011, and were formulated by an expert panel of specialist dietitians after a literature review of recent evidence. Recommendations have been made in terms of foods rather than nutrients wherever possible. Guidelines for education and care delivery, prevention of Type 2 diabetes, glycaemic control for Type 1 and Type 2 diabetes, cardiovascular disease risk management, management of diabetes‐related complications, other considerations including comorbidities, nutrition support, pregnancy and lactation, eating disorders, micronutrients, food supplements, functional foods, commercial diabetic foods and nutritive and non‐nutritive sweeteners are included. The sections on pregnancy and prevention of Type 2 diabetes have been enlarged and the weight management section modified to include considerations of remission of Type 2 diabetes. A section evaluating detailed considerations in ethnic minorities has been included as a new topic. The guidelines were graded using adapted ‘GRADE’ methodology and, where strong evidence was lacking, grading was not allocated. These 2018 guidelines emphasize a flexible, individualized approach to diabetes management and weight loss and highlight the emerging evidence for remission of Type 2 diabetes. The full guideline document is available at www.diabetes.org.uk/nutrition-guidelines.

High-cocoa polyphenol-rich chocolate improves HDL cholesterol in Type 2 diabetes patients

Diabet. Med. 27, 1318–1321 (2010)

Standing-based office work shows encouraging signs of attenuating post-prandial glycaemic excursion

Objectives The main aim of this study was to compare two days of continuous monitored capillary blood glucose (CGM) responses to sitting and standing in normally desk-based workers. Design, setting and participants This open repeated-measures study took place in a real office environment, during normal working hours and subsequent CGM overnight measures in 10 participants aged 21–61 years (8 female). Main outcomes Postprandial (lunch) measures of: CGM, accelerometer movement counts (MC) heart rate, energy expenditure (EE) and overnight CGM following one afternoon of normal sitting work compared with one afternoon of the same work performed at a standing desk. Results Area-under-the-curve analysis revealed an attenuated blood glucose excursion by 43% (p=0.022) following 185 min of standing (143, 95% CI 5.09 to 281.46 mmol/L min) compared to sitting work (326; 95% CI 228 to 425 mmol/L min). Compared to sitting, EE during an afternoon of standing work was 174 kcals greater (0.83 kcals/min; p=0.028). The accelerometer MC showed no differences between the afternoons of seated versus standing work; reported differences were thus a function of the standing work and not from additional physical movements around the office. Conclusions This is the first known ‘office-based’ study to provide CGM measures that add some of the needed mechanistic information to the existing evidence-base on why avoiding sedentary behaviour at work could lead to a reduced risk of cardiometabolic diseases.

High cocoa polyphenol rich chocolate may reduce the burden of the symptoms in chronic fatigue syndrome

BackgroundChocolate is rich in flavonoids that have been shown to be of benefit in disparate conditions including cardiovascular disease and cancer. The effect of polyphenol rich chocolate in subjects with chronic fatigue syndrome (CFS) has not been studied previously.MethodsWe conducted a double blinded, randomised, clinical pilot crossover study comparing high cocoa liquor/polyphenol rich chocolate (HCL/PR) in comparison to simulated iso-calorific chocolate (cocoa liquor free/low polyphenols(CLF/LP)) on fatigue and residual function in subjects with chronic fatigue syndrome. Subjects with CFS having severe fatigue of at least 10 out of 11 on the Chalder Fatigue Scale were enrolled. Subjects had either 8 weeks of intervention in the form of HCL/PR or CLF/LP, with a 2 week wash out period followed by 8 weeks of intervention with the other chocolate.ResultsTen subjects were enrolled in the study. The Chalder Fatigue Scale score improved significantly after 8 weeks of the HCL/PR chocolate arm [median (range) Exact Sig. (2-tailed)] [33 (25 - 38) vs. 21.5 (6 - 35) 0.01], but that deteriorated significantly when subjects were given simulated iso-calorific chocolate (CLF/CP) [ 28.5 (17 - 20) vs. 34.5 (13-26) 0.03]. The residual function, as assessed by the London Handicap scale, also improved significantly after the HCL/PR arm [0.49 (0.33 - 0.62) vs. 0.64 (0.44 - 0.83) 0.01] and deteriorated after iso-calorific chocolate [00.44 (0.43 - 0.68) vs. 0.36 (0.33 - 0.62)0.03]. Likewise the Hospital Anxiety and Depression score also improved after the HCL/PR arm, but deteriorated after CLF/CP. Mean weight remained unchanged throughout the trial.ConclusionThis study suggests that HCL/PR chocolate may improve symptoms in subjects with chronic fatigue syndrome.

Endothelial function and stress response after simulated dives to 18 msw breathing air or oxygen.

INTRODUCTION Decompression sickness is caused by gas bubbles released upon decompression. These bubbles have the potential to occlude blood vessels and damage the vascular endothelium. The aim of this study was to quantify damage to the vascular endothelium resulting from decompression by measuring endothelial microparticles (MP) and endothelial function. METHODS Five healthy male volunteers undertook a simulated (hyperbaric chamber) air dive and 1 wk later a second dive breathing 100% oxygen at 283 kPa (18 msw) for 60 min bottom time, decompressed with 5-min stops at 161 kPa (6 msw) and 131 kPa (3 msw). Endothelial function was tested pre- and postdive by reactive hyperemia peripheral artery tonometry (RH-PAT) and CD105 (Endoglin) positive MP were quantified by flow cytometry. Plasma E- and P-selectin, interleukin-6, and serum cortisol were also quantified. RESULTS RH-PAT showed a significantly decreased endothelial function post-decompression after breathing air when compared to oxygen (-0.33 +/- 0.27 vs. +0.18 +/- 0.14). CD105 MP pre- and postdive showed no change on the oxygen dive (460 +/- 370 to 360 +/- 163), however, they increased after breathing air (440 +/- 70 to 1306 +/- 359). There was no change in expression of CD105 on MP. Furthermore no changes were observed in plasma E- or P-selectin, IL-6, or serum cortisol. CONCLUSION From the data, at least in the time frame involved, there appears to be no detectable physiological/stress response to decompression, rather decompression from breathing air probably caused mechanical damage to the endothelium, resulting in both MP release and a reduction in endothelial function.

Obesity and gestational diabetes

The prevalence of both obesity and gestational diabetes mellitus (GDM) is increasing worldwide. GDM affects about 7% of all pregnancies and is defined as any degree of impaired glucose tolerance during gestation. The presence of obesity has a significant impact on both maternal and fetal complications associated with GDM. These complications can be addressed, at least in part, by good glycaemic control during pregnancy. The significance and impact of obesity in women with GDM are discussed in this article, together with treatment options, the need for long-term risk modification and postpartum follow-up.

High-polyphenol chocolate reduces endothelial dysfunction and oxidative stress during acute transient hyperglycaemia in Type 2 diabetes: a pilot randomized controlled trial.

To investigate the effects of high‐polyphenol chocolate upon endothelial function and oxidative stress in Type 2 diabetes mellitus during acute transient hyperglycaemia induced following a 75‐g oral glucose challenge.

The Effects of Resveratrol Supplementation in Overweight and Obese Humans: A Systematic Review of Randomized Trials

BACKGROUND Obesity and metabolic syndrome are significant global health issues, with current public health messages predominately focused on altering dietary and physical activity behaviors. Resveratrol is a polyphenol (stilbenoid) commonly found in grapes, and human trials to date have shown conflicting and limited beneficial effects with respect to health. The aim of this study was to determine the effect of resveratrol supplementation on reducing body weight and modifying associated inflammatory markers. METHODS A systematic review was undertaken following the PRISMA guidelines and using five indexed databases (OVID MEDLINE, Cochrane Library, Web of Science, SCOPUS, and CINAHL). A search strategy was formulated to select randomized, double-blind, placebo-controlled human trials investigating the effects of resveratrol supplementation on obesity or overweight, including body weight, metabolic and inflammatory markers. RESULTS Five thousand five hundred sixty-nine studies published from 1990 to November 2015 were identified, with only nine papers meeting the inclusion criteria. The studies involved 208 participants (aged 49.2 ± 8.3 years) and utilized a substantial range of resveratrol doses (75-3000 mg/day). Study durations were a minimum of 2 weeks (14-90 days). Seven studies indicated no significant change in body mass index or body weight (P > 0.05), and three studies showed no improvements in fat mass, fat volume, or abdominal fat distribution (P > 0.05). Four studies included measurements of inflammatory markers, with three of these finding resveratrol supplementation to have a significant positive effect (P > 0.05). CONCLUSION Based on the included studies, there is currently insufficient evidence to support the recommendation of resveratrol supplements in management of obesity. However, there were significant but not entirely consistent anti-inflammatory effects after resveratrol supplementation in overweight and obese individuals.

Sulphonyurea as a cause of severe hypoglycaemia in the community

INTRODUCTION Hypoglycaemia is a well recognised side effect of insulin and sulphonyurea therapy in the treatment of, patients with diabetes mellitus. METHODS We performed a retrospective analysis of patients who developed severe hypoglycaemia in Hull and, East Yorkshire, United Kingdom over a 4-month period to assess the different therapies that contribute the most to the problem and the patient groups who are at greatest risk. RESULTS Of the 75 patients with diabetes mellitus who developed severe hypoglycaemia, 61 (80%) were taking, insulin, 5 in combination with metformin. Ten (13%) patients were taking SU therapy; 5 in, combination with metformin, 2 in combination with a thiazolidinedione and 1 in combination with, insulin. When the SU-treated and non-SU treated groups were compared, patients taking SU therapy were, significantly older and had significantly lower HbA1c levels. CONCLUSIONS All patients taking SU and insulin treatment are potentially at risk of developing hypoglycaemia. Our, analysis shows that almost 15% of patients in our region who suffered from severe hypoglycaemia, were on SU therapy. Patients in this group were older and had lower levels of HbA1c. Whilst national HbA1c targets may be useful for clinicians to define glycaemic targets for their, population, this has to be tempered by what is in the best interests of the patient and not what is, dictated by the Quality and Outcomes Framework. Possible alternatives to SU therapy should be, considered especially if hypoglycaemia is a concern.

Tocotrienols, health and ageing: A systematic review

OBJECTIVES A systematic review of studies was undertaken to evaluate the potential effect of intake of tocotrienols or circulating levels of tocotrienols on parameters associated with successful ageing, specifically in relation to cognitive function, osteoporosis and DNA damage. METHODS Following PRISMA guidelines a systematic review of epidemiological observational studies and clinical trials was undertaken. Inclusion criteria included all English language publications in the databases PubMed and Scopus, through to the end of July 2016. RESULTS Evidence from prospective and case-control studies suggested that increased blood levels of tocotrienols were associated with favorable cognitive function outcomes. A clinical trial of tocotrienol supplementation for 6 months suggested a beneficial effect of intake on DNA damage rates, but only in elderly people. Regarding osteoporosis, only in vitro studies with cultures of human bone cells were identified, and these demonstrated significant inhibition of osteoclast activity and promotion of osteoblast activity. CONCLUSIONS Research in middle-aged and elderly humans suggests that tocotrienols have a potential beneficial anti-ageing action with respect to cognitive impairment and DNA damage. Clinical trials are required to elucidate these effects.