Jack Wyrick
Jack Wyrick

What's The Science Behind Caffeinating Cocktails?

Jack Wyrick
Jack Wyrick

As a bartender at a coffee shop/bar hybrid, I’m often asked to mix coffee and booze. Most of the time, it tastes good, but just don’t ask me to reuse your cooled-off partial cup of coffee—it’s a health code violation on soooo many levels.

Mixing caffeine and alcohol isn't new, but the process has garnered a lot of attention as of late. With the recent nationwide ban on various types of alcoholic energy drinks, the interaction between caffeine and ethyl alcohol has received a good deal of academic press.

Cups of Caveats

Caffeine may be the most studied drug in history, but the mechanics of how the molecule interacts with other substances is still largely theoretical. Outside of social/behavioral studies, the combination of booze and caffeine is especially hard to study because researchers can’t ethically give their subjects as much booze and/or caffeine as it would take to mimic real world binge drinking.

As a result, subjects can only consume moderate amounts of each. At these levels, it appears that they may feel drunk, but their reaction times aren’t significantly different from subjects given the placebo.

[Safety Note: If you’re going to experiment on your own, be careful. This should go without saying, but never drink and drive. The combination of caffeine and alcohol may make you feel less drunk, but your blood alcohol content (BAC) still works like you’re only drinking booze.]

Another challenge in studying the interactions of caffeine and hooch is that the amount of caffeine in any given drink may vary. For example, caffeine levels in coffee depend on how it’s grown, roasted, ground, and prepared.

To complicate things further, energy drinks can vary in size from 1 oz shots to 23 oz cans. Within the size differences, different brands use varying levels of caffeine in similar products. For researchers, the variation means that it’s difficult to figure out how much caffeine causes the manifestation of its negative effects.

Queen Caffeine

We know that all people absorb caffeine in roughly the same way. However, many factors including alcohol, pregnancy, and even grapefruit juice can extend the molecule’s half-life within the body.

We also know that alcohol affects each person differently based on his/her gender, body mass, water content, and food consumption. When drunk together, caffeine can somewhat override the sleepiness and ataxia (lack of voluntary coordination in movement) that come with heavy drinking. Alcohol, in turn, can suppress the anxiety/jitteriness that comes with too much caffeine. What causes these changes is less clear.

Caffeine is known to unselectively block adenosine (a neuromodulator believed to promote sleep and suppress arousal) receptors in the brain. Since alcohol raises the levels of adenosine outside of cells, it would normally cause a drinker to get sleepy. In this article from the Journal of Caffeine Research, researchers posit that caffeine curbs sleepiness and ataxia by blocking a specific adenosine receptor—A1.

Increased levels of adenosine may suppress caffeine’s anxiety-causing compounds. Caffeine may also affect how a slightly different adenosine molecule (A2A), interacts with dopamine receptors to amplify the effects of dopamine released into the brain by alcohol.

Hit the Lab

If you’re going to experiment with mixing these two substances, be careful. Caffeine may exacerbate alcohol’s addictive aspects, so drink in moderation. Be safe, kids.

Irish Coffee

1 oz Irish cream (I prefer Irishman)
1 oz Irish whiskey

Pour ingredients into a mug. Top with coffee or a latte (if you have an espresso machine handy).

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84 Years Ago Today: Goodbye Prohibition!
A huge queue outside the Board of Health offices in Centre Street, New York, for licenses to sell alcohol shortly after the repeal of prohibition. The repeal of prohibition was a key policy of Franklin Roosevelt's government as it allowed the government an opportunity to raise tax revenues at a time of economic hardship.
A huge queue outside the Board of Health offices in Centre Street, New York, for licenses to sell alcohol shortly after the repeal of prohibition. The repeal of prohibition was a key policy of Franklin Roosevelt's government as it allowed the government an opportunity to raise tax revenues at a time of economic hardship.
Keystone/Getty Images

It was 84 years ago today that the Twenty-First Amendment to the Constitution was ratified, repealing the earlier Amendment that declared the manufacture, sale, and transport of alcohol illegal in the United States. Prohibition was over! Booze that had been illegal for 13 years was suddenly legal again, and our long national nightmare was finally over.

A giant barrel of beer, part of a demonstration against prohibition in America.
Henry Guttmann/Getty Images

Prohibition of alcohol was not a popular doctrine. It turned formerly law-abiding citizens into criminals. It overwhelmed police with enforcement duties and gave rise to organized crime. In cities like Milwaukee and St. Louis, the dismantling of breweries left thousands of people unemployed.

Photograph courtesy of the Boston Public Library

Homemade alcohol was often dangerous and some people died from drinking it. Some turned to Sterno or industrial alcohol, which was dangerous and sometimes poisoned by the government to discourage drinking. State and federal governments were spending a lot of money on enforcement, while missing out on taxes from alcohol.

New York City Deputy Police Commissioner John A. Leach (right) watches agents pour liquor into sewer following a raid during the height of Prohibition.

The midterm elections of 1930 saw the majority in Congress switch from Republican to Democratic, signaling a shift in public opinion about Prohibition as well as concerns about the depressed economy. Franklin Roosevelt, who urged repeal, was elected president in 1932. The Twenty-first Amendment to the Constitution was proposed by Congress in February of 1933, the sole purpose of which was to repeal the Eighteenth Amendment establishing Prohibition.

American men guarding their private beer brewing hide-out, during Prohibition.
Keystone/Getty Images

With passage of the Constitutional Amendment to repeal Prohibition a foregone conclusion, a huge number of businessmen lined up at the Board of Health offices in New York in April of 1933 to apply for liquor licenses to be issued as soon as the repeal was ratified.

The Amendment was ratified by the states by the mechanism of special state ratifying conventions instead of state legislatures. Many states ratified the repeal as soon as conventions could be organized. The ratifications by the required two-thirds of the states was achieved on December 5, 1933, when conventions in Ohio, Pennsylvania, and Utah agreed to repeal Prohibition through the Amendment.

Workmen unloading crates of beer stacked at a New York brewery shortly after the repeal of Prohibition.
Keystone/Getty Images

A brewery warehouse in New York stacked crates past the ceiling to satisfy a thirsty nation after the repeal of Prohibition.

Keystone/Getty Images

Liquor wouldn't officially be legal until December 15th, but Americans celebrated openly anyway, and in most places, law enforcement officials let them.

Courtesy New District
Say ‘Cheers’ to the Holidays With This 24-Bottle Wine Advent Calendar
Courtesy New District
Courtesy New District

This year, eschew your one-tiny-chocolate-a-day Advent calendar and count down to Christmas the boozy way. An article on the Georgia Straight tipped us off to New District’s annual wine Advent calendars, featuring 24 full-size bottles.

Each bottle of red, white, or sparkling wine is hand-picked by the company’s wine director, with selections from nine different countries. Should you be super picky, you can even order yourself a custom calendar, though that will likely add to the already-high price point. The basic 24-bottle order costs $999 (in Canadian dollars), and if you want to upgrade from cardboard boxes to pine, that will run you $100 more.

If you can’t quite handle 24 bottles (or $999), the company is introducing a 12-bottle version this year, too. For $500, you get 12 reds, whites, rosés, and sparkling wines from various unnamed “elite wine regions.”

With both products, each bottle is numbered, so you know exactly what you should be drinking every day if you really want to be a stickler for the Advent schedule. Whether you opt for 12 or 24 bottles, the price works out to about $42 per bottle, which is somewhere in between the “I buy all my wines based on what’s on sale at Trader Joe’s” level and “I am a master sommelier” status.

If you want to drink yourself through the holiday season, act now. To make sure you receive your shipment before December 1, you’ll need to order by November 20. Get it here.

[h/t the Georgia Straight]


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