Maybe it’s obvious to you. But wishful thinking can be a powerful force for distortion. I mean, wouldn’t it be nice to think that tossing down a bottle of beer after a sweaty workout was actually the healthy thing to do?

And some people have claimed just that, notably an article in the Telegraph newspaper.

In a rare piece of good news for those who like a pint, Spanish researchers say beer can help someone who is dehydrated retain liquid better than water.

Prof Manuel Garzon, of Granada University, also claimed the bubbles in beer help to quench the thirst and that its carbohydrate content can help to replace lost calories.

Such reports have encouraged athletes to try quenching their thirst with beer, Luis Fernando Aragón-Vargas, told me.  I met  Aragón-Vargas at the American College of Sports Medicine meeting a couple of months ago. He is a professor of human movement science at the University of Costa Rica and was presenting a study addressing just that question.

“With runners and cyclists, it has become very popular to rehydrate with beer,” he said. “There are cyclists events where the destination is a microbrewery. That’s very dangerous because balance deteriorates by 36% compared to rehydrating with water.”

New Study Slams Beer

Aragón-Vargas and a colleague weighed 11 college men, tested their balance and reactions, then had them pedal on stationery bikes until they breathed or sweated out l2 percent of their weight.

Next the men drank Imperial brand beer with 4.6% alcohol until their body weights were back to their starting points. (On average that was 1.6 liters of beer containing about 60 grams of alcohol.) The researchers tested the men’s urine before and after. The men did the balance and reaction tests again.

Then also did the same experiment with water and Kaiser brand non-alcoholic beer.

The men were able to retain less water if they drank beer than if they drank water or non-alcoholic beer because beer made them pee more. Over the next three hours, they peed 1,218 milliliters after drinking beer,  compared to 745 milliliters after non-acoholic beer, and 774 milliliters of water.

Interestingly the men’s reaction time slowed for beer compared to non-alcoholic beer, but not compared to water. But their balance got worse with beer compared to both water and non-alcoholic beer.

“Regular beer with 4.6% alcohol was not a good choice for post-exercise rehydration,” the researchers concluded.

So what about that earlier study?

The findings were distorted, according to Adventure Sports Journal.

[If] you actually go to Professor Garzon’s website at the University of Granada and look under his list of scientific publications, you won’t find this study because it was never published. There’s even a bigger problem with this. Professor Garzon actually denies beer has any better hydration effect than water.

“Regarding the information that you cite, it has been taken wrong by the journalists,” responded the professor in an email, where he helpfully supplied his 166-page unpublished study of beer and hydration written in Spanish. And by the way, he goes by the name of Professor Manuel Castillo, not Garzon. “What we found is that rehydration with beer with a 4-5% alcohol level in a moderate amount, 660 ml (a little more than a pint), is not better, not worse than rehydration with water.”

And Aragón-Vargas thinks it’s wrong even to say Catillo’s study showed beer is “not better, not worse” because in Castillo’s study the subjects drank water along with their beer.

So drink beer after a work out if you want. Just make sure you’re doing it for fun, not health. Have some water with it. And don’t try to drive — or bicycle — home afterward.