30 June - 3 July 2008, Nottingham
The Nutrition Society (UK) held its annual summer conference at the University of Nottingham this week. The conference entitled “Multidisciplinary approaches to nutritional problems” consisted of a satellite symposium session, symposium sessions, original oral communications and poster communications.
The satellite symposium on Day 1 focused on the “Lipgene project”. Prof. Michael Gibney of University College, Dublin outlined the aim of the project; to investigate the interaction between dietary fat composition and genotypes (genetic variations) involved in the development of the metabolic syndrome (MS). He gave brief details on research that is being undertaken as part of the project. Following this Prof. Ian Givens of University of Reading highlighted that dairy products are the largest single source of saturated fatty acids (SFA) in the diet. He explained that milk has cardio-protective effects and therefore stressed that decreasing milk consumption is not the solution to decrease SFA intake. Prof. Givens explained that Lipgene has examined ways in which milk with a modified fatty acid profile [lower SFA and higher monounsaturated fatty acids content (MUFA)] can be produced through the alteration of the cows’ diet. The consumption of this milk has the potential to improve indicators of cardiovascular disease (CVD) in humans. Other presentations focused on the use of plant biotechnology to produce n-3 polyunsaturated fatty acid (PUFA) enriched poultry meat, and the impact of n-3 fatty acids on chronic disease outcomes.
Day 2 morning sessions saw a change in focus to ‘Performance, Exercise and Health’. Dr. Paul Greenhaff started the session with a presentation on how nutritional approaches can be used to enhance exercise performance. Further presentations focused on 1) dehydration, it’s affect on performance and how fluids can be used to attenuate the development of water deficit 2) the role of the sports dietitian in applying nutritional theory in practice 3) how exercise can improve health versus performance.
Within the original oral communication sessions results were presented from the ‘RISCK Study’; a multi-centre, randomised, and controlled dietary intervention study in subjects with increased risk of MS. Presentations were given by Dr. Susan Jebb of the MRC Human Nutrition Research, Cambridge and Prof. Tom Sanders of King’s College, London. The study was designed to investigate the affects of 4 different intervention diets; either low in fat or high in MUFA, with either a low glycaemic index (GI) or a high GI on metabolic risk factors that predispose to an increased risk of the MS. The findings presented indicated that there were no significant effects of the interventions on insulin sensitivity (Si); however the most favourable change in total to HDL cholesterol ratio was noted with the high MUFA/low GI diet.
The afternoon sessions began with Dr. Jeffery Friedman of Rockefeller University, USA presenting on the mouse ob gene and its encoded protein leptin which he discovered in late 1994. Dr. Friedman and his colleagues subsequently found that injecting mice with leptin decreased the weight of mice by reducing food intake and increasing energy expenditure. His current research focuses on leptin and its weight-reducing potential in humans. However at the end of his presentation he stressed that focus needs to be on improving the health of the obese through diet and exercise before any medical therapy is given.
The final presentation of the day was by Prof. Ricardo Uauy, of the London School of Hygiene and Tropical Medicine, entitled ‘Global nutrition challenges for human health’. In his lecture Prof. Uauy explained how obesity can stem from poor nutrition during pregnancy, leading to intrauterine growth restriction followed by rapid postnatal growth. He also touched on under-nutrition and the problem of feeding programmes providing protein energy-dense, micronutrient poor foods causing overfed children to become obese whilst remaining stunted.
The morning sessions of day 3 touched further on obesity, but focused on ‘Diabetes and Health’. Prof. Sorensen (University of Copenhagen) highlighted the challenges in the study of obesity due to the number of factors involved and highlighted 4 key elements involved in the development of obesity; 1) energy balance equation 2) self-promoting weight-gain 3) predisposition to obesity; genetic and non-genetic factors 4) obesigenic environment.
Dr. Nelia Steyn presented results from a review of successful interventions that have used a dietary component in diabetes prevention programmes. The review included 35 interventions and concluded that the most successful programs at helping to prevent diabetes emphasised weight loss through dietary counselling and included regular physical activity. Prof. Nick Wareham of Cambridge University highlighted the importance of exercise in reducing the risk of MS by presenting strong cross-sectional and longitudinal data showing an inverse association between physical activity and MS, however there is need for more trial evidence.
Prof. Michael Symonds presented on nutrition and its contribution to diabetes. He explained that the development of diabetes is likely to be a result of gradual changes in dietary patterns over many years, however diet is only one factor involved in the development of diabetes with disruption in the sleep-activity pattern being of high importance. There is some evidence to show that shorter sleep duration is association with increased risk of diabetes and it is also associated with a disruption in the regulation of appetite.
During the postgraduate symposium results from randomised, controlled trials on the affects of maternal prenatal supplementation on offspring health in later life were presented. There has been some positive research showing that maternal calcium supplementation may be associated with lower offspring blood pressure. One study in Argentina demonstrated that supplementation of 2g of calcium per day from 20 weeks gestation until birth decreased the risk of high blood pressure in offspring. However results from studies have not been consistent. A study in The Gambia failed to show an association between maternal calcium supplementation and blood pressure.
Day 3 finished with the ‘Silver Medal’ lecture presented by Dr Anne Marie Minihane of the University of Reading. Dr Minihane focused on Nutrigenetics; a concept of how genotype and diet interact to influence metabolic homeostasis, health status and the risk of diet-related diseases. It is hoped that advances in understanding of nutrigenetics will lead to ‘personalised nutrition’ in which nutrition advice may be given based on genotype. She presented research on the positive association between ApoE genotype and risk factors for coronary heart disease (CHD).
Day 4 included lectures on a variety of topics. The sessions commenced with Prof. Caroline McMillen from the University of South Australia presenting on nutrition in early life and its impact on health in later life. She presented research conducted in lambs that supports the concept that maternal obesity is associated with increased birth weight and fat mass in offspring and may be associated with an increased risk of becoming overweight or obese in childhood and adult life.
Within the original oral communication session results were presented on a systematic review and meta-analysis into protein intake and bone health. The review showed that most studies, including intervention studies showed a positive correlation between total dietary protein and bone mass density (BMD) in adults and also a positive association between animal protein alone and vegetable protein alone and BMD in adults. However large amounts of protein, especially animal protein may lower BMD. Intervention studies have failed to show a positive effect of dietary protein on fracture risk.
Prof. Jim Stevenson of University Southampton presented research on food additives and hyperactivity in children. The relationship between artificial food colour (AFCs) intake and hyperactivity was first suggested by Ben Feingold, however earlier studies could not substantiate any effect of AFCs. Prof. Stevenson presented the results from a recent randomised, double blind, placebo controlled study conducted in Southampton in 3 year old and 8 and 9 year old children. The study used a within subject, crossover design. The study found that 6 AFCs and a preservative (sodium benzoate) increased hyperactivity in children in the general population. The Food Standards Agency has considered public health implications of these findings and it has been recommended that EU regulations be changed to remove these 6 colours from food and drink and voluntary removal is to be in place in the UK by 2009.
The conference ended with a session on the environment and how environmental changes will impact on our food crop choices in the future held by Prof. Sayed Azam-Ali of University of Nottingham. In his presentation Prof. Azam-Ali considers the ‘physical’ environment e.g. rainfall, solar radiation and temperature and the ‘social’ environment e.g. human behaviour, consumer choices and government policies and how these impact on yields of food crops. He explained that climate change will influence what crops we grow, when we can grow them and where we can grow them and in turn the options we have for food crop choices in the future.