Guidelines Dietary - Eat For Health

Guideline 11.3 How dietary patterns can affect energy balance andweight outcomesEnvironmental and lifestyle factors resulting in overconsumption of energy in the diet and a decrease in physicalactivity are major contributors to the obesity epidemic. A small, persistent energy imbalance is enough tocause excess weight gain in both children and adults, which over time progressively increases the BMI. 135,139Available data from developed countries, including Australia, confirm an increase in energy intake concurrentwith the dramatic increase in the prevalence of overweight and obesity in children and adults since 1980. 139There has been much debate about the role of energy, carbohydrate and fat intake in the obesity epidemic. 236,259,260While reducing excess fat intake has been recognised as an important strategy to reduce energy intake in successfulweight loss interventions, 259 there is little evidence that population fat intake is associated with the obesity epidemicindependently of total energy intake. 260Foods with a higher energy density encourage energy intake above requirements. 198,261 Foods that are high inenergy density also tend to be more palatable, and high palatability is associated with increased food intake insingle-meal studies. 142,262 Fat and sugar are positively associated with energy density while water and dietaryfibre are negatively associated. Fat plays a role because of its high energy density compared to protein andcarbohydrates. Water and dietary fibre play a role through a dilution effect, although this is less for dietary fibrebecause of the much smaller range of fibre concentrations in food compared with both water and fat.It is plausible that the proportions of macronutrients (fat, carbohydrate, protein and alcohol) and types ofmacronutrients comprising total energy intake may affect an individual’s propensity to habitually overconsume.In this regard, dietary patterns that tend to be relatively low in total fat and moderate (not high) in carbohydrateare consistent with reduced risk of excess weight gain. Energy from drinks, in particular, may add to total energyintake without displacing energy consumed in the form of solid food, and it is plausible that sugar-sweeteneddrinks may contribute to excess energy intake through lack of impact on satiety. 216 The satiety value of foods mayalso be important in managing appetite and hunger. 263Energy-dense dietary patterns are associated with higher consumption of grain-based foods, fats and sweetsand lower consumption of vegetables and fruit. 264 International data suggest that the major foods contributing toincreased energy intake include sweetened drinks, snack foods and fast food 261,265,266 and that increasing portionsize is also an important contributor. 198,267,268 The low cost of energy-dense nutrient-poor food relative to nutrientdensefood also has a major role. 261,264The three key lifestyle areas related to overweight and obesity are dietary pattern, physical activity and behaviouralchange. Multicomponent interventions that address all three areas are more effective than those that addressonly one or two. Positive outcomes have been described, at least in the short term, in clinical weight lossregimes that include a range of interventions. 269,270 For further information, see the NHMRC Overweight andObesity Guidelines. 1211.4 Practical considerations: achieve and maintain a healthy weightIntentional weight loss in overweight and obese individuals reduces the risk factors for mortality and morbidity,and alleviates the symptoms of many chronic conditions. 269,270 It is not necessary to lose large amounts of weightto achieve substantial health gains. For example, it is estimated that a weight loss of 5 kg in all people who areoverweight or obese would reduce the national prevalence of type 2 diabetes by 15%. 271 Improving nutritionand/or increasing physical activity also benefits health in areas beyond weight control, such as bone strength,mental health and immune function. 2,272There is a need to provide population guidance on promotion of healthy weight, primary prevention of overweightand obesity, weight maintenance, weight loss, and management of weight-related conditions, disorders anddiseases. A focus on healthy weight is a more positive way to address weight issues than focusing on obesityand overweight. It encourages those who are a healthy weight to maintain that weight. It also helps to reducethe risk of any unintended negative consequences, such as disordered eating. Promotion of healthy weightincorporates prevention and management of underweight, overweight and obesity in children and adults andpromotes healthy growth in children.22EAT FOR HEALTH – australian dietary guidelinesNational Health and Medical Research Council