KEY POINTS:
More than 70,000 New Zealanders could be suffering an inferior state of mental health thanks to their own gambling or a relative's, new research estimates.
And those who get their gambling fix playing poker machines are likely to feel worse about themselves - mentally and physically -
than any other gamblers.
The Massey University Assessment of the Social and Economic Impacts of Gambling in New Zealand reported that the playing of gambling machines elicited more negative mental and physical feelings than TAB or on-track betting, while also affecting people's feelings about personal relationships, feelings about self, overall quality of life and overall satisfaction with life.
The report - carried out by the Centre for Social and Health Outcomes Research and Evaluation and Te Ropu Whariki - surveyed 7000 people nationwide.
More than 4200 said they had participated in some form of gambling in the past year, with half of those purchasing lottery products.
Other types of gambling were dramatically less popular, with about 20 per cent - 840 - choosing to play the pokies, and fewer than 10 per cent - 420 - betting on horses.
But researchers found that those who played poker machines, particularly in a bar setting, more often reported feeling their mental and physical health was poor, compared with other types of gamblers.
Maori and Pacific Islanders were more likely to play the pokies than other ethnic groups, and as a result, on average, reported a poorer self-rated quality of life than other races.
Report author En-Yi Lin said the survey was the largest nonpartisan report of its type, and was intended to document gamblers' "self perceptions": "They feel that their health is worse than others'."
Report co-author Sally Casswell said heavier gamblers tended to favour playing electronic gaming machines and many reported being "significantly worse off" in terms of mental and physical wellbeing.
"It is very much these continuous forms of gambling, where you are continuously poking the money in the machine."
The report findings, if applied across the entire population, would mean some 74,000 people were suffering as a direct result of their own or another's gambling, she said.
The report would "support very strongly" the need to examine the number and placement of machines throughout the country.
Problem Gambling Foundation spokesman David Coom described the findings as "totally not surprising".
The report was written for the Ministry of Health and Professor Casswell said it would be used to help formulate policy and funding programmes.