Reducing food portion sizes critical to tackle obesity, argue experts

Theresa Marteau from the University of Cambridge and colleagues recently published a Cochrane review that found the "most conclusive evidence to date" that people consume more food or drinks from larger size portions or packages, and when using larger items of tableware.

They showed that eliminating larger portions completely could reduce daily energy intake consumed by 12% to 16% among UK adults, and by 22% to 29% among US adults.

Following on from this, they discuss the policy changes that will likely be required to reduce the size, availability and appeal of large food and drink portions that could help to reduce over consumption, and prevent obesity.

They suggest the following:

• Reducing food and drink serving sizes that contain high amounts of calories such as the standard single serving of confectionery, chips and cakes
• Reducing availability of larger portion and package sizes, for example, by removing the largest serving size of drinks
• Placing larger portion sizes in stores and cafes less accessibly, for example, by limiting portion size at checkouts, aisle ends, and special displays
• Restricting pricing practices that enable larger portion and package sizes to cost less in relative terms than smaller sizes, and restricting price promotions on larger portion and package sizes
• Highlighting single portion sizes in packaging
• Restricting portion and package sizes in advertisements
• Making smaller tableware, including plates, cups, glasses, and cutlery, the default for self service and served foods and drinks
• Designing tableware to encourage smaller mouthfuls, such as, shallow plates, straight sided glasses, cutlery
• Pricing tableware in relation to size

They say the implementation of portion size interventions will be easier in public sector organisations, such as schools, hospitals, military bases, and prisons, than in industry.

Such changes will "pose major challenges," they add, and suggest a combination of regulatory and non-regulatory measures as the food industry may find it difficult to act without regulation given "first mover disadvantage."

In addition, they say that reducing portion sizes may mean going back to sizes of portion and tableware similar to those in the 1950s, and changes may even involve reductions of over 50% for some energy dense products.

This is "far greater than the estimated 5% reductions currently offered and negotiated with the food industry," as part of the UK's Public Health Responsibility Deal.

They add that "disincentives or sanctions for non-participation in voluntary agreements may also help," and interventions must also take into consideration industry innovations that may overcome the intended effects of policy approaches.

Lastly, they say "although policy makers and the food industry have primary responsibility for action, public acceptability is likely to be an important facilitator." For example, they highlight the case of many tobacco control measures that reflected the mobilisation of public support.