The global obesity epidemic is not being tackled effectively, experts have said.

According to their claims, which are published in The Lancet medical journal, childhood obesity rates have jumped significantly in less than a generation and while these rates have started to level off in some countries, no country to date has recorded a decline in childhood obesity.

In fact, efforts to tackle the problem worldwide have been ‘unacceptably slow', with just one in four countries introducing healthy eating policies up to 2010.

According to the article's co-author, Dr Tim Lobstein of the World Obesity Federation, it is estimated that children in the US are eating an average of 200 extra calories per day when compared with their peers in the 1970s. This is an extra $400 (€350) worth of food per child per year, or $20 (€17.5) billion for the food industry in the US.

"Fat children are an investment in future sales," commented Dr Lobstein.

He pointed out that the food industry has a particular interest in targeting children, as if they are repeatedly exposed to processed foods and sweetened drinks, they will develop a taste for these products, which can lead to brand loyalty and big profits.

This year alone, the processed infant food market is expected to be worth $19 (€16.6) billion. In 2007, it was worth $13.7 (€12) billion.

Yet most countries are not taking any regulatory steps to protect children from the effects of obesity. Instead, most rely on voluntary moves by the food industry, despite there being no evidence that these are effective.

According to Dr Christina Roberto of the Harvard T.H. Chan School of Public Health in the US, people's understanding of obesity ‘must be completely reframed if we are to halt and reverse the global obesity epidemic'.

"On one hand, we need to acknowledge that individuals bear some responsibility for their health, and on the other hand recognise that today's food environments exploit people's biological (e.g. innate preference for sweetened foods), psychological (e.g. marketing techniques), and social and economic (e.g. convenience and cost) vulnerabilities, making it easier for them to eat unhealthy foods," she said.

She insisted that this ‘vicious cycle of supply and demand for unhealthy foods' can be broken with smarter food policies by governments, as well as efforts by industry and civil society.

The experts call for a change in food policies, such as taxes on unhealthy food products like sugary drinks, subsidies on healthier foods for low-income families like fruit vouchers, an international code of marketing when it comes to children's health and the regulation of food quality in schools.

The experts emphasised that the answers do not just lie with governments, but with all of society. They also pointed out that health professionals are poorly prepared to deal with obesity and called for better training in this area.