Ground-breaking research by Cancer Council Victoria has found gradual weight gain between early and mid-adult life increases a person’s risk of obesity-related cancers by 30 to 50%.
New findings from the Melbourne Collaborative Cohort Study found young adults in the normal weight range who became overweight in their 20s and 30s were at greater risk of 13 types of cancer than those who maintained a healthy weight throughout adulthood.
The findings are based on a study which followed over 30,500 Victorians for up to 27 years, to assess the association between body mass index (BMI) measurements over their adult life and obesity-related cancer incidence.
Associate Professor Roger Milne, Head of the Cancer Epidemiology Division at Cancer Council Victoria, where the study was conducted, said the findings further highlight the importance of maintaining a healthy weight.
“We compared adults who were a normal weight in their early 20s and maintained a healthy weight, with those who started at a similar weight but became overweight or obese. We found that the greater the increase in BMI, the higher the risk of obesity-related cancers, so that, relative to those who maintained a healthy weight, those who became overweight by middle-age were 30% more likely to develop one of these cancers, while those who became obese were 50% more likely,” Dr Milne said.
Cancer Council Victoria CEO, Todd Harper, said the data confirm the important role weight control plays in preventing certain cancers.
“The Cancer Council estimates that about 3,900 cancer cases in Australia each year are linked to being above a healthy weight, so we cannot ignore the risk that weight gain poses to our health,” Mr Harper said.
“The important message for Victorians is to maintain a healthy weight throughout adulthood and to try and avoid weight creeping up as you get older. It’s cumulative weight gain that can often go unnoticed day-to-day which is what we are concerned with here.”
The findings are being announced as Cancer Council Victoria’s ‘13 types of cancer’ TV and radio campaign hits the airwaves across the state from Monday 7 October.
The TV advertisement features Melbourne surgeon Dr Ahmad Aly exposing in graphic detail the link between obesity and 13 types of cancer by depticing dangerous toxic fat around a patient’s internal organs. The ad homes in on sugary drinks as a key contributor to weight gain.
“It’s vital we work hard to help people understand the link between being above a healthy weight and cancer and encourage them to take steps to reduce their risk,” Mr Harper said.
“Along with moving more and eating a healthy diet, we’re encouraging Victorians to cut sugary drinks from their diet as one clear way they can reduce their cancer risk. It’s also important for people to know their own BMI measurement and how to keep it at a stable level. For specific advice about BMI or managing your weight we advise people speak with their GP.”
Obesity Policy Coalition Executive Manager, Jane Martin, said the findings illustrate the need for the Victorian Government to develop, fund and implement a comprehensive strategy in order to slow the march of obesity in the state.
Ms Martin pointed to the pervasive nature of advertising and marketing of unhealthy food as a key driver contributing to the poor health of Victorians’.
“We know unhealthy food and drink companies spend over $45 million in advertising, bombarding Victorian children and adults with junk food meal deals and cheap sugary drinks every day,” Ms Martin said.
Ms Martin praises the way the ‘13 types of cancer’ campaign prompts Victorians to adopt healthier habits but wants to see changes made by governments, the food industry and communities in order to make a lasting impact on the health of Victorians.
“This is not a problem without a solution. We have strong consensus from public health, community and academic groups who have identified recommendations in A Healthier Start for Victorians to tackle our childhood obesity crisis. Prohibiting advertising, promotion and sponsorship in public owned and managed spaces is just one of the eight key recommendations we need to commit to.
“Queensland and the ACT have already taken the initiative to protect their state from the relentless push of unhealthy food and drink marketing by committing to phasing out these ads. It’s time the Victorian Government match other governments’ efforts to support healthy weight for Victorians,” Ms Martin said.
Case study: Jacqueline Russell available for interview
Following cancer diagnoses in her family, mother of three, Jacqueline Russell decided to make healthier life choices to reduce her own cancer risk.
“When both my mum and dad were diagnosed with cancer I was shocked. It came as a real wake up call and I realised I needed to make healthier choices to reduce my own risk of developing cancer so I can be around for a long time with my kids.”
“I started exercising, minimised my sugar and salt intake and became more mindful of what I was putting in my body.”
“Sticking to healthy habits was hard at first - growing up, I rarely ate vegetables, sprinkled sugar on my cornflakes and regularly sipped on sugary drinks. It was the norm in our household. But when I focused on the benefits of eating healthy and all the nutrients my body would absorb, it made the choice a lot easier. Now I’m grateful for being able to live a fulfilled and healthy life.”
About the campaign:
The 13 types of cancer campaign will run for 6 weeks on TV and radio and across social media channels as well as outdoors across the state.
A dedicated campaign website cancervic.org.au/healthyweight provides factsheets for health professionals and consumers and digital elements about how to make small lifestyle changes to improve people’s health.
About the research:
Title: Body mass index trajectories and risk of obesity-related cancers: findings from the Melbourne Collaborative Cohort Study
Authors: Yi Yang, Allison M Hodge, Roger Milne, Dallas English, Pierre Dugue and Brigid Lynch. The reseach was conducted by Yi Yang, a PhD student at the Cancer Epidemiology Division and The University of Melbourne.
