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External influences on eating behaviour, such as portion size, have been reliably shown to influence food intake in the laboratory. However, little research has examined whether laboratory settings under or overestimate the effect that external influences have on food intake compared to when studied in the real-world. In Study 1, 60 participants (mean age = 32 years) were randomized to consume a large (200 g) or small (100 g) portion of popcorn under controlled laboratory conditions and during a separate session in their home. Results showed that the effect of portion size on food intake was larger at home (d = 0.97) than in the laboratory (d = 0.56). Furthermore, participants reported feeling more relaxed eating at home compared to the laboratory. In Study 2, we examined whether comparable results were observed in a semi-naturalistic laboratory designed to resemble a home setting. 59 participants (mean age = 28 years) completed the same procedure as Study 1 in a standard and a semi-naturalistic laboratory setting. Although participants reported having higher levels of private self-awareness in the standard laboratory, the effect that portion size had on food intake did not differ between the standard laboratory (d = 0.50) and the semi-naturalistic laboratory (d = 0.49). The impact that external influences on eating, such as portion size, have on food intake in the real-world may be underestimated when studied under laboratory conditions. [ABSTRACT FROM AUTHOR]

Portion size impacts on the amount of energy consumed during a meal. However, research findings on participant characteristics that moderate the effect of portion size on energy intake are mixed. Using data pooled across three randomized control trials, we examined the impact of reducing meal portion size on meal energy intake in 111 adult participants varying in sex (55 M, 56 F), body weight (BMI range = 19-42) and a broad range of participant characteristics, including usual portion size, restrained, emotional and external eating, satiety responsiveness, plate clearing tendencies, concerns about wasting food and self-control. In each trial, a repeated-measures design was used and participants consumed three ad-libitum lunchtime meals differing in portion size; large-normal portion size condition (100%) vs. small-normal portion size condition (~ 75%) vs. smaller than normal portion size condition (~ 50%). In mixed ANOVAs, we did not find convincing evidence that any participant characteristic reliably moderated the impact that reducing portion size had on energy intake. For the majority of participants energy intake decreased when portion size was reduced and it was more common for participants to consistently reduce their energy intake than consume a similar amount when portion size was reduced. We also found little evidence that a sub-group of participants existed whose energy intake was consistently resistant to portion size reductions. Portion size may be a universal driver of energy intake, as reducing meal portion size appears to decrease meal energy intake among most people. Food portion downsizing may therefore be an equitable intervention approach to reducing population level energy intake. [ABSTRACT FROM AUTHOR]

Skin cancer presents a significant public health burden in Australia. The present study aimed to supplement population-based estimates of sun protection behaviour by examining setting-specific trends in directly observed sun protection in public outdoor leisure settings. Repeated cross-sectional observational surveys of adolescents and adults were conducted on summer weekends between 11 am and 3 pm from 1992 to 2002, 2006 to 2012, and 2018 to 2019 (N = 44,979) at pools/beaches and parks/gardens within 25 km of the centre of Melbourne, Victoria. The primary outcome was a binary index representing individuals having above or below the median level of body surface covered by hat, shirt, and leg garments in each setting type. The prevalence of above-median body coverage increased between 1992 and 2002 in both settings. At pools/beaches, a slight decline in above-median body coverage between 2006 and 2019 in males and females (adjusted odds ratio, AOR = 0.96 [0.94, 0.97]; 0.94 [0.93, 0.95]) appeared to be driven by a decline in leg coverage, while arm coverage, hat, sunglasses, and shade use remained stable. At parks/gardens, a decline in above-median body coverage between 2006 and 2019 (AOR = 0.90 [0.89, 0.91]; 0.94 [0.93, 0.95]) was accompanied by small declines across other protective behaviours that varied between males and females. Patterns in protective behaviours observed in outdoor leisure settings may reflect the changing composition of individuals choosing to remain outdoors during peak UV times and highlight the importance of continued promotion and monitoring of the use of multiple measures to protect against UV damage in Australia. [ABSTRACT FROM AUTHOR]