According to the Australian Institute of Health and Welfare 67% of adults aged 18 and over are overweight or obese. When broken done by gender, it’s slightly more common in men than women.
Weight gain is obviously the core problem, and a particular area of focus is understanding when and why it happens. Part of the picture suggests it may be cultural celebrations such as New Year or Christmas that are chiefly responsible for annual weight gain. Other research lays responsibility at the feet of the seasons – that we gain weight in winter and shed it in summer. These patterns aren’t well understood in Australia, but some new research aimed to make the picture clearer.
A new study from researchers at the University of South Australia and the University of Queensland recruited more than 300 Adelaideans aged 18 to 65. They were asked to wear Fitbits for a year and to record their weight daily. At the start of the study, the baseline weight of the participants was 84 kilograms on average. The participants were broadly and evenly spread over the normal, overweight, and obese BMI categories.
Researchers found that a typical person’s weight tended to fluctuate about 250 grams on a week-to-week basis. Considered over a year, the participants gained about 220 grams on average. Weight tended to increase sharply between December and January (about a 500-gram increase), then gradually decreased until April (the start of autumn), increased through to the end of winter and then eased again when spring arrived.
The researchers say these findings are evidence of both seasonal and cultural influences on weight with colder months leading to steady weight gain and sharp increases at Christmas and Easter. They also found a weekly pattern, with people heaviest after a weekend, which is probably no surprise since most of us change our diet from Friday through to Sunday. The authors say these significant increases in weight at specific times might warrant targeted weight-related interventions.
Further information
Weekly, Seasonal, and Festive Period Weight Gain Among Australian Adults – JAMA Network
Obesity and overweight – myDr.com.au