A new study published in The Lancet Diabetes & Endocrinology journal suggests that reducing sugar content in sugar sweetened drinks (including fruit juices) in the UK by 40% over five years, without replacing them with any artificial sweeteners, could prevent 500,000 cases of overweight and 1 million cases of obesity, in turn preventing around 300,000 cases of type 2 diabetes, over two decades. The study is by Professor Graham MacGregor1 and colleagues at Queen Mary University of London, UK.

Based on the UK's salt reduction experience, which has seen salt content in many food products successfully reduced by 40% over five years, the authors decided to do a study on the effects of a similar reduction in added sugars. Using national representative data from National Diet and Nutrition Survey rolling programme (NDNS RP) years 2008-2012 and British Soft Drinks Association annual reports, the authors calculated sugar sweetened beverage (SSB) consumption level (both with and without fruit juices) and its contribution to free sugar and energy intakes in the UK population.

They then estimated the predicted reduction in energy intake resulting from the proposed strategy at individual level and modelled the predicted reduction in body weight for each adult. By scaling up the distribution of the predicted body weight in the NDNS RP to the UK adult population, the reduction in the number of overweight, obese, and diabetic adults were estimated.

The calculations showed that a 40% reduction in free sugars added to SSBs over five years would lead to an average reduction in energy intake of 38.4 kcal (calories) per day by the end of the 5th year and this would lead to an average reduction in body weight of 1.20kg in adults, resulting in a reduction in overweight and obese adults by approximately 0.5 million (1.0%) and 1.0 million (2.1%) respectively. This would in turn prevent 274,000-309,000 obesity-related type 2 diabetes over the next two decades.

If fruit juices were excluded from SSBs, the corresponding reduction in energy intake and body weight would be 31.0 kcal/day and 0.96 kg respectively. This would result in a 0.7% (0.3 million cases) reduction in overweight and a 1.7% (0.8 million cases) reduction in obesity, which would in turn prevent around 221,000-250,000 diabetes cases over two decades. The predicted impact was greater in adolescents, young adults, and individuals from low income families who consume more SSBs.

The authors say: "The appreciation of sweetness can adapt to gradual changes in sugar intake, and it is unlikely that the proposed strategy will influence the consumers' choice provided the gradual reduction is done over five years."

They add that previous research has shown that the calories lost from SSBs are unlikely to be replaced by other sources, and that a reduction in added sugar has little influence on the cost and price the product and therefore is unlikely to affect sales and profit of the soft drink industry. It is therefore potentially attractive to industry, although some parts of the industry - for instance, the sugar industry - may be resistant.

The authors continue: "The proposed strategy could lead to a profound reduction in energy intake from sugar-sweetened beverages and could therefore lower the prevalence of overweight, obesity, and type 2 diabetes in the long term. These findings provide strong support for the implementation of the proposed strategy."

They conclude that "Individuals should also reduce their consumption of sugar-sweetened beverages in the long term, but this can be difficult because of the advertising power of industry. Our proposed strategy provides an innovative and practical way to gradually reduce energy intake from sugar-sweetened beverages and its combination with other strategies, including a tax on sugar-sweetened beverages, would produce a more powerful effect."

Writing in a linked Comment, Dr Tim Lobstein, Director of Policy, World Obesity Federation London, UK, and Curtin University, Perth, WA, Australia, says that the study brings a very positive message to policy makers.

He concludes that "Policies can be developed that have the potential to quickly change behaviour and begin to reduce the prevalence of obesity and related diseases. Other measures also need to be taken, not least to restrict the inducements to consume unhealthy food - which are beamed at children through much of the media they use - as well as the implementation of a soft drinks tax, as proposed by Public Health England, the Parliamentary Health Committee, and the ambassador for healthier diets, Jamie Oliver. In combination, such measures could have a substantially greater effect on sugar consumption than in isolation, bringing even greater relief to the over-stretched budgets of the UK's health services."