How many drinks can I have and still be allowed to drive? – Karen, Toronto.
Canada's low risk alcohol guidelines say people shouldn't drink and drive, period.
"It's difficult to give guidance that people will read in an article and then get pulled over and say: 'The Globe and Mail [newspaper] told me I could have X-many drinks,'" says OPP Chief Superintendent Don Bell, with the Canadian Association of Chiefs of Police traffic committee. "It's kind of funny, in Ontario, youth can't drive if they've been drinking anything up to age 21 – so why, at over 21, is it suddenly okay to drink and drive? Why not just keep the same mindset?"
The Criminal Code of Canada defines impaired driving as blood alcohol content (BAC) at or above .08, which is 80 milligrams of alcohol for every 100 ml of blood. But, every province except Quebec has administrative laws that allow police to suspend your licence on the spot if your BAC is over .05 (.04 in Saskatchewan and .06 in the Yukon)
"If you consume alcohol in a responsible way and consume two standard drinks if you're a man, one if you're a woman and nothing over that, you'll never be over the .05 per cent limit," says Andrew Murie, chief executive officer, MADD Canada. "There's no scientific evidence supporting .08 – it's just way too high. Most countries that base these things on science and not politics have moved way lower. At .08, it would take a 200-pound guy seven straight drinks in two hours, on an empty stomach, to blow a criminal level."
Most provinces forbid young drivers to consume any alcohol and be behind the wheel.
"Young drivers are bad enough drivers as it is, you add alcohol and it's horrific," Murie says.
How many drinks it will take to get to a specific BAC depends on gender (fewer drinks for women), height, weight and whether your liver's working properly. The bigger you are, the more blood you have and the more drinks it will take.
Provincial governments used to distribute charts that show what BAC is, depending on weight and gender, after a number of drinks over time. They still exist online and in apps.
"Essentially, these things were eliminated a number of years ago because the charts may not be accurate for all races – the enzyme in the liver that eliminates alcohol works at different rates – and the charts were only accurate for Caucasians," says Raynald Marchand, general manager of programs with the Canada Safety Council.
Marchand says he and his wife take turns driving and letting the other have a glass of wine with dinner – but he says people should understand how drinks affect them.
"We're not a nation of teetotallers – if you drink responsibly and allow enough time, then your blood alcohol content will be minimal," he says. "The Criminal Code is not intended so people can't go out for dinner and enjoy a glass of wine. But it got a little complex and all the groups out there and the government and so on will say that there's no safe level of alcohol."
If you have that beer at the start of the meal and linger for an hour and a half, you probably won't register any alcohol at all, Marchand says.
"But if you have that glass of wine with dessert, you should wait – that's not enough time to process it."
And, coffee, food or a brisk walk won't make the alcohol go through your system any faster – it simply takes time.
Marchand says most impaired drivers in crashes are well over the .08 limit.
"The number of collisions under .05 is pretty minimal and might have happened anyway," he says. "But a big problem is sober drivers hitting pedestrians who have been drinking – you really need to watch out if you're anywhere near bars or restaurants."
MADD Canada's Murie would like to see labelling on bottles, cans and menus that states how many standard drinks a beverage contains.
"I'm not talking about warning labels, but labels that say 'This beer has x number of standard drinks,' so people can follow the guidelines, enjoy alcohol responsibly and not cause death and carnage in the road," Murie says. "Anytime an individual has to become their own liquor control board, there's a problem — people need to be educated."
What's on tap
You can easily go over the limit if that drink or two is bigger than you realize. A standard drink serving contains 13.5 grams of alcohol and might be smaller than most of us think:
- 12 ounces (341 ml) of beer, cider or cooler with 5 per cent alcohol.
- 5 ounces (140 ml) of wine with 12 per cent alcohol.
- 1.5 ounces (43 ml) of distilled alcohol (such vodka, gin or rye) with 40 per cent alcohol.
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