Obesity research reveals new clues by age and stage

The research study funded by Cancer Councils around Australia and the National Heart Foundation found that out of 12 188 students studied, just under one in four were either overweight (18%) or obese (5%). 

They also found that overweight or obese students were more likely to be male, to come from a lower socioeconomic background, engage in less physical activity, spend more time using electronic media and sleep for a shorter duration.

“These findings suggest that preventive measures should include a particular focus on facilitating physical activity and reducing sedentary behaviour, as well as promoting adequate sleep”, the authors wrote.

Another study in the same issue of the MJA found that as body mass index (BMI) increased in pregnant women, so did the frequency of complications and adverse outcomes such as hypertension in pregnancy, gestational diabetes, caesarean section, perinatal mortality, stillbirth and neonatal mortality.

The study, by Professor David McIntyre, head of Mater Clinical School, and coauthors, also found that preterm birth and neonatal morbidities including hypoglycaemia, jaundice, respiratory distress syndrome and neonatal intensive care unit admission rose as maternal BMI increased.

“Maternal BMI serves as a marker of pregnancy risk that can aid in the care of individual women and help plan appropriate allocation of maternity health care resources”, the authors wrote.

Associate Professor Helen Skouteris and coauthors from the school of psychology at Deakin University Discipline of Pediatrics & Child Health, the University of Sydney, have called for more research on both actual and optimal physical activity levels in preschoolers, in a review in the same issue of the MJA.

International guidelines vary, although Australian guidelines call for at least 3 hours of activity a day for preschoolers, according to the authors; yet some studies show preschoolers are falling well short of these.

“We argue that age groupings are needed because toddlers and preschoolers, school-aged children and adolescents are physiologically and developmentally different from each other. These developmental differences need to inform age-specific recommendations”, they wrote.

Associate Professor Anthea Magarey from Nutrition and Dietetics, School of Medicine, at Flinders University, described obesity as a “non-age specific condition of increasing global prevalence”, in an accompanying editorial.

She noted that in Australia, 55% of women, 68% of men and 25% of children and adolescents are overweight or obese and a coordinated approach involving multiple sectors and agencies is essential.

“While national and state-based programs are important initiatives, broader environmental change that encompasses urban design and infrastructure (eg, safe streets, access to parks and pools in less affluent areas) is an essential element of the solution”, she wrote.

And though bariatric surgery is becoming an increasingly popular solution to weight loss, exercise is still a valuable part of the health equation for overweight and obese people, wrote Winthrop Professor Daniel Green from the School of Sports Science, Exercise and Health at the University of Western Australia and his coauthor in the same issue of the MJA.

The authors pointed out that even when exercise had no impact on weight, it could still increase skeletal muscle and lean body mass, decrease cardiovascular risk and mortality and progression to diabetes.

“Medical professionals who deal with overweight and obesity should prescribe exercise because exercise is good for you, whether you lose weight or not”, Winthrop Professor Green wrote.

The Medical Journal of Australia is a publication of the Australian Medical Association.

The statements or opinions that are expressed in the MJA reflect the views of the authors and do not represent the official policy of the AMA or the MJA unless that is so stated.

CONTACTS:                    A/Prof Anthea Magarey                                   0467 543 809

                                    Prof Daniel Green                                           0408 196 801

                                    Mr Michael Sinclair-Jones                                 0400 700 783
                                    University Media Manager, University of Western Australia

                                    A/Prof Helen Skouteris                                    0414 409 563

                                    Ms Lisa Dibbs                                                 07 3163 1975
                                    Director of Marketing at the Mater
                                    (on behalf of Prof David McIntyre)

                                    Mr Glen Turner                                                0412 443 212
                                    Director, Communications, Cancer Council Australia

                                    Ms Kirsten Andrews                                          0413 777 404
                                    National PR Manager, Heart Foundation