A New Zealand coroner has ruled against a global drinks giant in a case that is likely to reverberate around the planet.

David Crerar has found that mother-of-eight Natasha Harris died from drinking too much Coca-Cola.

Ms Harris, of Invercargill, died, aged 30, in February 2010. Evidence at her inquest showed she drank up to 10 litres of "classic" Coke every day - equal to more than twice the recommended safe daily limit of caffeine, and almost one kilogram of sugar.

Coca-Cola has argued the huge quantities of Coke she drank could not be proven to have contributed to her death.

But in findings issued yesterday, Mr Crerar said: "When all of the available evidence is considered, were it not for the consumption of very large quantities of Coke by Natasha Harris, it is unlikely that she would have died when she died and how she died."

The soft drink company was not to blame for her death, he said, although its product was a contributing factor.

He recommended the Government consider imposing caffeine and sugar warnings on soft drinks, such as those already compulsory on energy drinks.

In the months before her death, Ms Harris' health had deteriorated, partner Chris Hodgkinson told the inquest. "She had no energy and was feeling sick all the time . . . She would get up and vomit in the morning."

Her Coke habit had become an addiction: "She would get moody and get headaches if she didn't have any Coke, and also feel low in energy."

Mr Crerar found that she died from cardiac arrhythmia after Mr Hodgkinson found her slumped on the toilet, gasping for air. She had myriad medical conditions, including a racing heart and "absent teeth", which her family say had rotted out from Coke consumption.

She drank between six and 10 litres a day. Mr Crerar estimated that, at the 10l level, she was consuming 2 times the recommended maximum daily amount of caffeine, and more than 11 times the recommended maximum sugar intake.

Those ingredients, combined with a poor diet, caused her to develop an enlarged liver, an electrolyte imbalance and, ultimately, led to her death. She also had symptoms of caffeine overdose.

Yesterday, Coca-Cola Oceania spokesman Josh Gold said the coroner should not have focused on Ms Harris' Coke "addiction", because one of the contributing expert witnesses - Professor Johan Duflou, a forensic pathologist contracted by Coca-Cola to give evidence - disagreed with the other expert witnesses.

"The coroner acknowledged that he could not be certain what caused Ms Harris' heart attack," Mr Gold said. "Therefore we are disappointed that the coroner has chosen to focus on the combination of Ms Harris' excessive consumption of [Coke], together with other health and lifestyle factors, as the probable cause of her death.

"The safety of our products is paramount . . . All of our products have a place in an active, healthy lifestyle that includes a sensible, balanced diet and regular physical activity."

Ms Harris' mother, Lynette, said yesterday that she did not hold Coca-Cola responsible for her death. "It was her choice to drink Coke."

Mr Hodgkinson said warning labels should be put on Coke bottles, especially for the benefit of children. "So long as they get the warnings out there, I will be happy. I don't want any other kids to go through what our kids have gone through."

A Ministry of Primary Industries spokesman said New Zealand shared food labelling standards with Australia, and the ministry was currently chairing a trans-Tasman working group reviewing policy guidelines on the addition of caffeine to foods.

REVEALING THE RISKS

David Crerar recommends that health authorities and Coca-Cola consider issuing warnings on soft drinks.

"The hazards to the health of the consumers of excessive quantities of sugar and caffeine contained in carbonated drinks could be more clearly emphasised.

"Consideration should be given . . . to either lowering the caffeine percentage limit or creating a more specific warning such as those printed on [energy drinks] produced and marketed by Coca-Cola."

IS COKE ADDICTIVE?

In the coroner's findings, Professor Doug Sellman of the National Addiction Centre said Coke should be added to an international list of addictive substances.

"Growing neurobiological research is strongly indicating that some people can develop a compulsive habit . . . very similar to the same behavioural pattern observed in a drug addiction."