Scientists have issued a stark warning about the global obesity epidemic, saying that governments have to take drastic action.

The problem has been "escalating for decades, yet long-term prevention efforts have barely begun and are inadequate", according to a new paper from international public health experts published in The Lancet. In a special four-paper series, the latter notes estimates of 1.46 billion adults and 170 million children overweight or obese worldwide in 2008 and "if we continue without successful interventions", the projections for 2030  estimate 65 million more obese adults in the USA and 11 million more in the UK alone. This means an additional 6-8.5 million people with diabetes, 5.7-7.3 million with heart disease and stroke and 492,000-669, 000 with cancer.

The Lancet goes on to say that projected costs to treat these additional preventable diseases are an increase of $48-$66 billion per year in the USA and £1.9-£2 billion per year in the UK. It notes that "health systems everywhere are already struggling to contain costs. Without prevention and control of the risk factors for obesity now, health systems will be overwhelmed to breaking point".

 Voluntary deals with food and drink firms do not work

The journal believes "governments' reactions so far are wholly inadequate and rely heavily on self-regulation by the food and beverage industry, and the so-called nudge approach". It states that the UK government, in particular, "has made it clear that only voluntary agreements with food and beverage companies are on the agenda, and many of the public health committees are made up of large numbers of these very industry representatives. So do these voluntary agreements work? All indications so far are that they do not".

The Lancet argues that "the obesity epidemic will not be reversed without government leadership" and "business as usual would be costly in terms of population health, health care expenses, and loss of productivity". It adds that "we need to accurately monitor and evaluate both basic population weight data and intervention outcomes", stating that "a systems approach is needed with multiple sectors involved".

Regarding the forthcoming high-level United Nations meeting on non-communicable diseases (September 19-20) in New York, The Lancet concludes that it is "marred by the reluctance of some to set targets" and "one immensely important next step in the fight against non-communicable diseases could be the agreement on a framework convention on obesity control". The journal ends by asking "who will take the lead?"

Lead author of one of the Lancet papers, Steven Gortmaker, of the Harvard School of Public Health, suggests imposing tax on sugar-sweetened beverages and limiting marketing of unhealthy foods, an approach that has been effective in tobacco control. He also recommends school-based education and nutrition and physical activity programmes for children and some weight loss interventions.