The Truth Behind “Beer Before Liquor”

2 minute read
Originally posted here: https://mcgill.ca/oss/article/did-you-know-health/beer-liquor

Have you ever heard the saying “beer before liquor never been sicker”? Or “liquor before beer, you’re in the clear”? What about “grape or grain but never the twain”? Well, it turns out that there might be some truth to at least some of these adages.

There are a few factors to consider here.

First, there’s the absolute volume of alcohol you are consuming. Looking at the Manhattan as our example cocktail, it contains roughly 28% alcohol by volume (ABV), which makes it seem much less potent than, say, straight whiskey, with its ABV of 40%. But it’s not really fair to compare these drinks on their ABVs since the amounts consumed tend to be different.

What matters isn’t the ABV of a drink, but the true amount of pure alcohol (ethanol) in a drink. In the chart below you can see a comparison of drinks’ ABVs, volumes, and actual amounts of ethanol.

DrinkABV (%)Volume of
1 Drink
(mL)
Absolute Amount of
Alcohol in 1 Drink (oz)
Beer63550.72
Wine121500.6
Manhattan281401.31
Bloody Mary122200.9
Straight vodka40450.6

So you can see that, even though we tend to consider one glass of wine, cocktail, or can of beer equal to “one drink”, the actual amount of alcohol you’re consuming can vary wildly by what kind of drink you are having.

The volume difference in drinks also influences how quickly we drink them. A beer tends to take longer to drink than a cocktail, or especially a shot, simply because it’s much larger. Purely based on volume, you could drink 2.5 Manhattans in the time it takes to drink one bottle of beer. So, by drinking beer, you essentially give yourself a lower alcohol per minute rate of consumption than when drinking cocktails.

If your options are only to drink cocktails and then beer, or beer and then cocktails, it makes sense to keep your heavier drinking for the beginning of your night. When you’re more sober you’ll be better able to pace yourself, evaluate how you’re feeling, and make changes to your rate of consumption if need be. Later in the evening, when your decision-making process is already compromised, beer is a safer option that won’t contribute as much to making you more intoxicated.

There is however another factor at play here: how well your body absorbs alcohol in different preparations. A 2007 study found that the vodka served diluted (with carbonated or still water) was absorbed faster than the vodka served neat. This means that even if the same amount of time is taken to drink straight liquor or a glass of wine (two drinks which contain about the same absolute amount of alcohol) the wine still may leave you more intoxicated, as it is better absorbed into your blood.

As for the grape or grain advice? Feel free to ignore it. A 2019 study compared the hangover severities of subjects who drank only beer, only wine, beer and then wine, or wine and then beer, and found that “neither type nor order of consumed alcoholic beverages significantly affected hangover intensity.”

Testing Drivers for THC Is a Lot Harder Than Testing Them for Alcohol

3 minute read
Originally posted here: https://mcgill.ca/oss/article/health/testing-drivers-thc-lot-hard-testing-them-alcohol

To test drivers for alcohol consumption, we have the breathalyzer. It’s fast, reliable, portable and inexpensive, but it will not work for cannabis.

We’ve been testing for THC (the main psychoactive part of cannabis) for a very long time. Our problem is not detecting it, but doing so with a portable machine in a non-invasive way.

As far as existing tests go, urine tests are commonly used for athletes or other employees undergoing drug tests. THC can be detected for anywhere from 1-30 days after use, depending on the frequency of use and the body fat of the individual (since THC is fat soluble).

False positives can result from consuming a variety of things: hemp seeds, ibuprofen, naproxen, and even Prevacid (an antacid). Luckily, a blood test can differentiate between true and false positives. Unluckily, blood tests for casual users of cannabis are only effective at detecting THC for about 1 day after consumption.

An alternative is a hair test. For that, the top 1.5 inches of a strand of head hair is tested. Body hair can also be used, though finding a 1.5-inch piece of leg or arm hair may be difficult. THC can be detected in hair up to 90 days post-consumption, although hair treatments like perms or dyes can affect results. This method is very sensitive and does not create false positives, though it does take longer than a urine test.

The quick and portable test that the Canadian government has settled on using is saliva-based. It’s called the Dräger DrugTest 5000. It requires only 0.28 mL of saliva, produces results in minutes, and even though very little THC passes from the blood into the saliva, the limit of detecting is low enough to still detect the compound.

The DrugTest 5000 is used in Australia, Germany and the UK. But it alone will not be the sole method of measuring intoxication of drivers. In addition to measuring the THC in a driver’s saliva, police will be allowed to perform field sobriety tests, and watch for telltale signs that someone is intoxicated.

Besides cannabis, the DrugTest 5000can detect opiates, benzodiazepines, cocaine, amphetamines and methamphetamines, though it does so for a hefty price: about $6000 per unit. It is only usable when the temperature falls between 4 and 40 ˚C, and can show false results if the subject has recently eaten or smoked.

This study took blood and saliva samples from 369 drivers and tested them using the DrugTest 5000 and traditional blood test methods (UHPLC-MS-MS). The DrugTest 5000 was correct in its assessment about 85% of the time for THC. This means that a false positive or negative reading would be given roughly once in every eight tests. Not really the best numbers.

The rate of false negatives is much better for the DrugTest 5000 when detecting methamphetamine (6.1%), opiates (0%) or cocaine (0%), although the rates of false positives (38.4%, 65.5% and 87.1%) are still quite high. False positives would at least be revealed as falsepositives upon blood test, a better alternative to letting an intoxicated driver free on the roads, but a 1 in 8 chance of a false reading is not what I’d hope for from the technology used by the Canadian police.