Regularly having more than two rinks a day increases the risk of developing alcoholism, alcoholic liver disease, and some forms of cancer. Having between one to two alcoholic drinks a day has been shown to have positive effects on health, unless contraindicated, chiefly because of its cardiovascular effects. A few researchers have questioned the extent of positive effects as most studies compare moderate drinkers health to non-drinkers, but fail to take into account the amount of people who abstain because they are already ill, rather than lack of alcohol causing their ill-health.