Giving up alcohol for a month is pointless for people's health, says a leading liver expert.
Professor Robin Fraser, medical director of the Canterbury Medical Research Foundation, says instead drinkers should stay off booze for a few days every week throughout the whole year.
Thousands of Kiwis are on the wagon for Dry July to raise cash for cancer sufferers. But Professor Fraser warned abstainers should be wary of claimed health benefits and a longer-term attitude to alcohol was more desirable.
"The liver is like an oil refinery for the blood and works best with regular maintenance, which means staying off the booze a few days a week.
"A danger of stopping for a month is many problem drinkers will convince themselves they don't have an issue. However, once they start drinking again, in no time they are back consuming as much as ever."
Simon Adamson, associate professor at the National Addiction Centre, believed Dry July may not have many medical benefits but it was a good way for people to consider their drinking habits.
"Anything that makes alcohol into a popular discourse is good," he said. "It is also useful for people who are not drinking to observe the altered behaviour of those around them who are still on the booze."
Ginny McCarthur, from Pukekohe, is participating in Dry July for the third time. The personal trainer and nutritionist finds laying off booze for a month is fraught with temptation.
"The worst part is having to walk past the gin bottle at the end of a hard day.
" But I definitely feel better in the mornings ... and I usually lose a few kilos during Dry July."
Media personality Kerre McIvor, an ambassador for Dry July, said an alcohol-free month probably led to changes in the drinking habits of some participants.
"Some people decide ... 'I quite like the feeling of not drinking' and don't drink as much or [decide] 'I'm going to take out time regularly'."
Stars signed up:
*Jono Kenyon (Step Dave)
*Jacquie Nairn (Shortland Street)
*Spencer Falls (Shortland Street)
Read more stories about Dry July here.