Politicians in the United Kingdom have called for a review of government guidelines on alcohol consumption. Alongside its current recommendation that people should limit their total alcohol intake to three to four units per day for men and two to three units for women (there are about two units in a glass of wine), members of a House of Commons committee said the U.K. health department should advise citizens to take at least two days off from drinking each week.
Canada already includes this "drink holiday" recommendation in its alcohol guidelines, while the United States does not. Considering these mixed messages, which consumption pattern is actually healthiest? Will it really benefit your health to two take nights off from drinking each week?
According to Thomas Greenfield, senior scientist at the Alcohol Research Group (ARG), a government-funded research organization based in Emeryville, Calif., the argument in favor of "drink holidays" is that heavy drinkers might find it easier to take occasional breaks from drinking than to drink less each night. The hope is that their overall consumption would decrease if they didn't drink two nights out of seven.
"Absent a change in a heavy daily amount, holidays would make sense," he told Life's Little Mysteries, a sister site to LiveScience.
However, in Greenfield's view, the drink holiday message is "inherently confusing." By putting a cap on people's weekly alcohol consumption, then saying people should confine that consumption to just five days, the recommendations imply that people can raise their daily intake when they do drink, as long as they keep two days alcohol-free. For example, if you consume around 14 or 15 alcoholic drinks per week, the drink holiday recommendation implies it would be better to have three drinks daily for five days than to have two drinks daily over the course of a week. (In this case, a "drink" is equivalent to a pint of beer or a glass of wine.)
In fact, scientists recommend the opposite. "Spreading this drinking over more days and at a lower amount per day would be best, I believe," Greenfield said. Studies suggest that one alcoholic drink per day can actually decrease your stroke risk, while large amounts — four drinks per day or more — raise it. Lower amounts of alcohol also keep you from getting drunk, putting you at a lower risk of injury and helping you avoid a hangover. [Is There a Hangover Cure?]
A 1995 study by a group of Canadian epidemiologists even found that daily drinking is associated with less social harm — behavior requiring police intervention, destruction to friendships, relationships, work life and health — than more erratic drinking patterns.
Furthermore, experiments on animals imply that taking time off from drinking may actually increase alcohol dependence. "There is some animal evidence that instating heavy drinking and then forcing abstinence (but on a longer cycle) actually increases dependence or addiction. Alcoholics who periodically (but not forever) quit may be an example of this. Of course, it is not clear what a weekly cycle of this type does," Greenfield wrote.
Deborah Dawson, senior clinician in the Laboratory of Epidemiology and Biometry at the National Institute on Alcohol Abuse and Alcoholism, said the idea of a nondrinking day may have originated as a tool for helping individuals with a prior history of alcohol abuse gauge their state of dependency. "In that group, such an idea may make sense as an indicator that the individual hasn't relapsed to a state of impaired control" — if you can quit at will, you aren't hooked — "but I don't know of the evidence to support it as a preventive measure for the general population."
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