Food Safety campaigners are calling for a ban on diet drinks and other artificially sweetened products in schools after a Wellington woman said she was poisoned by sugar-free chewing gum.

Abigail Cormack, 25, said she began suffering muscle cramps, heart palpitations, anxiety, depression and skin rashes after chewing gum that contained the artificial sweetener aspartame.

Her symptoms disappeared when she stopped her four-pack-a-day habit.

A spokeswoman for the Wrigley company, which makes Extra chewing gum, said aspartame - which is used in more than 6000 products consumed by 200 million people worldwide - was the "most tested food additive in history".

More than 200 studies supported the safety of aspartame, the company said.

"Wrigley Australia and New Zealand is committed to ensuring that all safety food standards are met for all of our confectionery products, including gum," it said.

Since aspartame was 200 times sweeter than sugar, it was only used in "minuscule" amounts, and was composed of ingredients found naturally in food.

However, Green MP Sue Kedgley - who is campaigning to have fizzy drinks containing aspartame removed from schools - said the Government had a responsibility to warn the public.

"The problem is that products containing aspartame are being touted as a healthier alternative and this means that many children are being exposed to potentially large doses of this artificial sweetener," she said.

"While it's important to reduce the sugar intake of children and adults, to replace that sugar with a controversial additive is just not the answer."

Safe Food Campaign spokeswoman Alison White said the use of this "questionable" additive had more to do with "power, politics and money" than science.

"It is interesting and predictable that the research showing problems with aspartame is all independently funded," she said.

Ms Cormack's case was likely to be "the tip of the iceberg".

Khandallah man Clive Bennett said he believed he had aspartame poisoning while living in Britain five years ago. He suffered muscle pains and dizzy spells while taking sugar substitutes in three coffees a day.

After reading about aspartame poisoning, he stopped using artificial sweetener and his problems disappeared.

"It annoys me when scientists and food companies say there is no proven link to anything bad. More likely, they know there's a problem but they won't admit it."

Auckland woman Cathy Norman blames aspartame used to sweeten soft drinks for her heart palpitations, blackouts and unexplained seizures.

At one time, she was drinking two litres or more of diet soft drink a day.

"I think the doctors thought I was making it all up ... But when I changed my diet and I cut out aspartame from my diet altogether, I have not been sick like that since."

Clinical pharmacologist Professor Carl Burgess, from the Wellington School of Medicine, said to get aspartame poisoning from a diet soft drink, one would have to drink 28 cans in one sitting.

However, he said some people were more sensitive to additives than others.

"You might test a product on 5000 people but if it causes an adverse reaction in one in 100,000 people, you're unlikely to find it."