For many children Halloween is the chance to eat what they want and how much they want.

However parents are being asked to watch the amount of sweets their children consume over Halloween.

This warning has been prompted by medical experts as concern grows about the increase in childhood obesity .

Dr Michael Kramer, child health and development expert at the Canadian Institute of Health Research (CIHR) said, “I don’t think the indiscretion of a single day or a couple of days around Halloween would have any measurable impact on that child’s health.”

The problem is when children consume the same amount after Halloween, this stretches to Christmas and beyond. That’s when long-term problems can arise.

According to Dr Kramer a child that consumes an extra 100 calories a day may not seem like a lot by over a period of a year the child has eaten 36,500 extra calories.

Dr Diane Finegood, nutrition and diabetes expert and the CIHR said, “In a sense our society has prolonged the Halloween experience.”

In America, $5 billion is spends on candy during Halloween. This works out to be about $20 being spent just to hand sweets out for tricks and treats according to a survey by the National Retail Federation.

Dr Finegood added, “If you walk through a grocery store and look at the packaging of food intended for children, almost all of it really links the ideas of fun with food .

“The food industry has recognised it can sell food by linking it to fun. That takes the concept of fun and food — which Halloween did once a year — to an everyday experience.”

The rate of childhood obesity in America has tripled between 1980 and 2004, according to Trust for Americas Health, a non-profit organisation. They say 25 million children are overweight .

With childhood obesity is the risk of type diabetes, which normally occurs in adults.

Parents are being encouraged to give alternatives to children rather than sweets. Dr Finegood concluded, “There are ideas out there for things to give away, things that are fun, but they don’t eat.”