GLASGOW'S public health chief has criticised the food offered at Commonwealth Games venues and warned that authorities must act to ensure the feel-good factor created by the success of the event is not squandered.

Linda de Caestecker hit out at organisers for the amount of high-fat fast food available at venues and said she felt it was a missed opportunity to encourage healthier eating.

The director of public health for NHS Greater Glasgow and Clyde added that the positivity around the Games should be seized upon to prompt lasting changes in people's lifestyles and that it should not be taken for granted that the event will have a long-term impact on public health.

Glasgow 2014 said that sports fans had been offered the "freedom to choose" from a range of foods.

But Dr de Caestecker, who attended rehearsals for the opening ceremony at Celtic Park and athletics events at Hampden Park, said the fare offered had left a sour taste from a health perspective.

While she said she would have favoured a trial where only healthy options were offered at venues, she would also have backed the promotion of healthy options where items such as burgers and chips were also on sale.

But she believes that organisers had paid only lip-service to encouraging healthy eating, with some token products advertised unavailable in reality. She said a more positive approach at live zones and festivals, where a diverse range of street food had been on offer, showed that an alternative had been possible.

"This could have been a great opportunity to sell healthier options in fast-food outlets but the vans outside the venues still emphasised high-fat, high-calorie food," she said. "Inside the venues there was some attempt at healthy options - low-fat pies and butternut squash pies but it seemed half-hearted and my experience was that these options sold out."

While Dr de Caestecker said there was limited evidence that large-scale sporting events encouraged people to take up sport, she praised healthy messages given out by athletes including sisters Louise and Kimberley Renicks, who both won individual golds for Scotland in Judo. Louise told how her sister had given up Irn-Bru and said "You have to be sensible with what you're putting in your body". The 31-year-old added that while they had still been able to socialise, they had been careful not to stay out too late or overindulge."

The car-free scheme, which encouraged spectators to travel on foot or by public transport to venues, as well as designating Glasgow 2014 as "smoke-free" games, were also successes, according to Dr de Caestecker.

But she said: "It's a jump to say by watching elite athletes, people want to get more active, although some of the infrastructure might help. The positive energy and pride people felt is more likely to encourage people to think they can have a healthy lifestyle, rather than seeing Usain Bolt running in a time that no-one can emulate.

"The feeling that things can change is as important as new facilities. The reaction has been fantastic and the fact people feel so positive about the city is wonderful. Glasgow was pro-active in terms of trying to plan the legacy, but we need to really think about how we can capitalise on that and keep it going.

"It will take effort. Evidence from the London Olympics was that it lasted six months."

Glasgow 2014 insiders insisted efforts were made to ensure food and drink at venues was provided by Scottish suppliers, such as oat firm Stoats, and fruit company Bruce's of Balmyle among those involved.

A spokesman said: "Glasgow 2014 catering covered consumer demand from the wide range of people attending, from athletes to spectators of all ages and workforce, and a broad range of menu choice, including healthier options, were on offer.

"Ultimately, people consume many different foods and beverages and were offered the freedom to choose from a diverse range of options that can be enjoyed as part of an active, healthy lifestyle."