Users of ‘diet’ drinks who think that sweetness is calories

Improving weight loss RCTs. Measuring the step weight change from a sustained change in frequency of a particular eating or exercise pattern

The public’s trust in the science of avoiding unhealthy weight depends on a radical reform of the design and execution of weight loss programmes and their clinical trials. This Perspective reiterates the longstanding argument for measuring the effectiveness of each component of an intervention on obesity. Body energy content change results from a difference in rates between input and output. These rates are determined by the frequencies of specific patterns of dietary behaviour, physical activity and thermal comfort, plus the cost of resting metabolism. Since fat-free mass changes alongside fat mass, the amount of change in weight from a change in the frequency of a behaviour pattern comes to an asymptote. That step change in weight per unit of behaviour change is measured by regression from the change in frequency of the behaviour that has been maintained from baseline to follow-up. For hard evidence, weight loss programme participants’ own words must be used to specify behaviour. In RCTs of multiple-component programmes, sequences of the behaviour patterns to be changed are randomised among groups. The resulting evidence on effective slimming practices can be delivered directly into therapeutic services and public health interventions for the culture investigated.

The Use of Nonnutritive Sweeteners in Children

The prevalence of nonnutritive sweeteners (NNSs) in the food supply has increased over time. Not only are more children and adolescents consuming NNSs, but they are also consuming a larger quantity of NNSs in the absence of strong scientific evidence to refute or support the safety of these agents. This policy statement from the American Academy of Pediatrics is intended to provide the pediatric provider with a review of (1) previous steps taken for approved use of NNSs, (2) existing data regarding the safety of NNS use in the general pediatric population, (3) what is known regarding the potential benefits and/or adverse effects of NNS use in children and adolescents, (4) identified gaps in existing knowledge and potential areas of future research, and (5) suggested talking points that pediatricians may use when discussing NNS use with families.

How well do Australian shoppers understand energy terms on food labels?

OBJECTIVE

To investigate nutrition literacy among adult grocery buyers regarding energy-related labelling terms on food packaging.

DESIGN

Qualitative interviews and quantitative surveys to determine shoppers' understanding of energy terms ('energy', 'calories' and 'kilojoules') and how energy terms affect perceptions of healthiness and intentions to purchase breakfast cereals, muesli bars and frozen meals.

SETTING

Individual in-depth interviews and surveys in two metropolitan supermarkets, Sydney, Australia.

SUBJECTS

Australian adults (interview n 40, survey n 405) aged 18-79 years.

RESULTS

The relationship between energy and perceived healthiness of food varied by product type: higher energy breakfast cereals were perceived to be healthier, while lower energy frozen meals were seen as healthier choices. Likewise, intentions to purchase the higher energy product varied according to product type. The primary reason stated for purchasing higher energy products was for sustained energy. Participants from households of lower socio-economic status were significantly more likely to perceive higher energy products as healthier. From the qualitative interviews, participants expressed uncertainty about their understanding of kilojoules, while only 40 % of participants in intercept surveys correctly answered that kilojoules and calories measured the same thing.

CONCLUSIONS

Australian consumers have a poor understanding of energy and kilojoules and tend to perceive higher energy products as healthier and providing sustained energy. This has implications regarding the usefulness of industry front-of-pack labelling initiatives and quick service restaurant menu labelling that provides information on energy content only. Comprehensive and widely communicated education campaigns will be essential to guide consumers towards healthier choices.

Perception as Interacting Psychophysical Functions. Could the Configuring of Features Replace a Specialised Receptor?

This paper illustrates how perception is achieved through interactions among the psychophysical functions of judged features of an object. The theory is that the perceiver places processed features in a multidimensional space of discriminal processes. Each dimension is scaled in units of discrimination performance. The zero coordinate of each feature is its level in an internal standard (norm) established by previous experience of that category of object in context. Experiments are reported which show that one, two, or three concurrent single-featured objects matched the multiple features of another object in two ways. Either stimulation from the two objects had discrimination distances from norm that added, or the stimulation by one object was processed through a concept describing stimulation by the other object. It follows that, in this case, perception via a receptor for the multi-featured object can be replaced by a point of balance among receptors for each single feature. The object with its own receptor is the gustatory stimulant L-glutamic acid as its monosodium salt. The features that stimulate diverse gustatory receptors of their own are sodium chloride, citric acid, sucrose, and caffeine. A more complex approach to dimensional coding was developed earlier for photoreceptors in colour judgments. The present approach is modality independent, mathematically simple, and economical in experimental data.

Targeting cultural changes supportive of the healthiest lifestyle patterns. A biosocial evidence-base for prevention of obesity

This paper argues that the rise in obesity can be slowed only by universal education based on a type of evidence that does not yet exist. On top of literacy and numeracy, people need the ability to preempt the fattening effect of a decrease in habitual physical activity by altering familiar patterns of eating, drinking and exercise in ways that are both maintainable within the individual's social and physical environment and also effective at decreasing weight to the asymptote for each sustained change. Hence the prevention of obesity requires locally valid evidence on which changes to specific customary habits actually do avoid unhealthy fattening. Interventions need to focus on antecedents to individuals' common lapses from the healthy changes in these customs. Yet no research has been funded into the public's descriptions of feasible changes that cause a step down in weight, let alone into the environmental conditions for individuals' maintenance of those changes. As a result, public health policies on obesity lack scientific basis. When will a start be made on systematic identification of cultural supports to readily executed patterns of lifestyle behaviour which improve health to extents that have been directly measured?