The Cochrane Review on portion sizes - from publication to informing policy

The Cochrane Review on portion sizes - from publication to informing policy

The Cochrane Review, 'Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco published in September 2015 from the Cochrane Public Health Group found significant evidence that people consume more food or non-alcoholic drinks when offered larger sized portions or when they use larger items of tableware.

Since then, for over a year now, the evidence from this Cochrane Review has been one of the most important and most cited public health stories of 2015 worldwide.

The review has received extremely high levels of media and public interest, and during the last 12 months has informed Public Health England’s report on sugar reduction continuing to influence the public and policy debate on tackling obesity.

Here’s its story from publication to informing policy.

How it began
The Behaviour and Health Research Unit (BHRU) is based in the Department of Public Health and Primary Care, within the School of Clinical Medicine at the University of Cambridge, UK. It is funded by the UK Department of Health Policy Research Programme. BHRU contributes evidence to national and international efforts to achieve sustained behaviour change to improve health outcomes and reduce health inequalities. The unit focuses on the excessive consumption of food and alcohol, inactivity and smoking, as changing these behaviours positively would help to prevent the majority of the preventable non-communicable diseases, including many cancers, cardiovascular disease, and diabetes.

After conducting scoping exercises, the BHRU realized that there was a large body of evidence around portion, package and tableware sizes, which was of significant policy relevance, yet hadn’t been brought together. Over the course of over two years, they carried out a complex Cochrane Review on portion, package and tableware sizes, which was published in the Cochrane Library in September 2015.

The review evidence, comprising data from 72 studies and over 6,700 participants, showed that people consume more food and non-alcoholic drink when offered bigger portions, bigger packaging, or bigger tableware rather than smaller sizes, regardless of factors such as gender, BMI, or self-control. The review’s findings suggest that cutting the size of portions, packages, and tableware may present a potential path for helping to tackle obesity, which impacts a quarter of British adults, costing lives, quality of life, and the NHS.

Immediately following publication, the review received extremely high levels of media and public interest globally.

Coverage of the review included BBC News, national and regional BBC radio, ABC News (Canada), Channel 9 News (Australia), as well as international and UK publications such as The New York Times, Times, Guardian, Independent, Telegraph, Daily Mail, The Atlantic, Vice, The Spectator, and NHS Choices.

The publication of the Cochrane Review was shortly followed by a BMJ Analysis article entitled ‘Downsizing: policy options to reduce portion sizes to help tackle obesity’, designed to draw attention to the policy implications within the review.

Impact since publication
This Cochrane Review immediately sparked fresh impetus to a policy discussion on tackling the global healthcare issue of obesity. It attracted extremely high levels of media and online attention, the extent of which was reflected in its inclusion in Altmetric’s Top 100 of 2015, which measures the attention received by academic articles. Within three months of publication, the Altmetric score (measuring online news coverage and Twitter attention) for this review placed it #1 for all Cochrane Reviews ever (#1 of 7496) and in the top 500 (top 0.01%) of all articles ever published (#436 of 4,632,100).

Since publication, the Cochrane Review has been cited in Public Health England’s (PHE) October 2015 publication Sugar reduction: The evidence for action report, which had been commissioned by the Department of Health to help feed into the Government’s childhood obesity strategy.  PHE’s report highlighted BHRU’s review to argue for the benefits of reducing portion sizes.

In addition, Professor Susan Jebb OBE, who was part of the review team, provided oral evidence to the Health Committee’s childhood obesity inquiry, during which she echoed Dr Alison Tedstone, Director of Diet & Obesity at PHE, on the important impact of portion size and mentioned the Cochrane evidence.

Finally, in Australia, the findings of the review were shared with the Victorian Health Promotion Agency (VicHealth). Their subsequent citizen jury, aiming to develop actions to promote healthier eating and tackle rising rates of obesity, recommended that beverage sizes should be regulated and a maximum size that can be sold through restaurants and retail outlets (soft drinks and other calorie-dense beverages) should be imposed (Jury’s report).

Cochrane author Ian Shemilt from the University of Cambridge talks about his experiences disseminating this review

Additional Information:

Read the Cochrane Review and summary

You may also be interested in:


Friday, December 9, 2016