Obesity will become the biggest single issue for the industry within the next five or 10 years, according to a new survey of 187 food and drink industry leaders.

About 60% of senior executives from major retailers and suppliers such as Kellogg's and Mars UK believed obesity would be the biggest issue in the survey by food and retail research consultant Allegra.

"There's a feeling among executives that something must be done about obesity before it bites back in the form of a public backlash against the oversupply of food," said Allegra MD Jeffrey Young. "The executives feel the government must carve out more policies to encourage healthy eating."

The survey also found nearly 70% of chief executives and senior managers felt brand identity would become even more crucial in creating a point of difference over the next five years.

With regards to the country's most admired food and drink brands, Innocent came top, followed by Pret a Manger, M&S, Starbucks Coffee and Tesco. Young said M&S's Simply Food initiative had given it the edge over Tesco.

Half of those polled in the survey said they thought rising food costs would remain a huge challenge.

Other challenges included innovation and NPD, sustainability and attracting and retaining staff.

Ethical sourcing, reducing carbon footprint and packaging were the top three future ethical areas of focus for the senior executives.