I used to see this ad every time we drove through the Valley—it’s hard to miss.

(See above!)

In case you can’t see the picture, the ad says that this beer has:

  • 50% less calories than wine per millilitre
  • 80% less carbs than a regular beer.

But how many calories are we talking about?

This beer has less calories than what?

Wine! (50% less calories than wine per mL—look, it says so…)

If you weren’t paying attention, that ad would tell your brain you could have 2 beers for the same number of calories of 1 glass of wine.

But that would be the biases at work—the distinction bias means we love a good comparison. And the anchoring bias sets a point of reference in our head that determines where we place every other related bit of information.

Even if it’s an irrelevant point of reference. In the case of advertising—especially if it’s irrelevant.

A randomly selected white in my cellar (a carefully chosen $6 bottle) is 12.5% alcohol.  A standard drink of white wine is about 110mL. *

At 4.5% alcohol, a standard drink of beer is about 253.5mL.

So this beer might be half the calories per millilitre, like it says … but you need twice as many millilitres to have had ‘one drink’. Or else, you’re stuck with this one:

110 ml of beer isn't much

What about less carbs than regular beer, then? (80% less, and don’t fall for that ‘per mL’ thing again)

You won’t have to—did you notice this part isn’t about calories? This is about ‘carbs’. (Although, incidentally, the website does say ‘30% less calories than regular beer’ too)

The Oxford Dictionary defines a ‘carbohydrate’ as anything in

… a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water (2:1) and typically can be broken down to release energy in the animal body.

That’s a big group of things …

The definition that’s used more often is the one that describes ‘foods that are high in carbohydrates’—all the yummy stuff like bread and pasta.

I’m no dietician, but I gather that the carbs people worry about are usually the ‘simple carbohydrates’—the ones easily converted to sugars. But, as we’ve just seen, there are other carbs—which include fibre and other vegetable matter.

Recently, I read a couple of studies about low-carb beer that suggest:

there is little, if any, difference in either the amount of alcohol or the total energy content of traditional and low-carb beers, suggesting ‘low-carb’ may not be a nutritionally significant improvement

[1]

So the 80% less carbs in the ad … they’re not necessarily the ‘simple carbohydrates’.

And what’s a regular beer anyway? It’s the one that you have at 5.30pm every day on your way to the train, of course!

A bit of context

I might have ranted at length at this ad—but I do get that it’s been put out in reaction to another kind of bias.

A recent survey—admittedly commissioned by Lion Nathan (who own most of the beer you’ll find everywhere in Australia)—showed that 94% of participants overestimated the amount of sugar in beer. And anecdotally, a lot of people think beer is worse for you than wine.

So, Lion Nathan have decided to release nutritional information on their beers—which can only be a good thing.

Just make sure you read the information for yourself—and not the way a very large billboard tells you to.

 * According to the ad, the 50% less calories thing was based on the ‘average calorie content of the leading 100 wine SKUs in Australia’—but they lost me at ‘average’. So I just pulled the number from a real world example in my hand to match the numbers on their beer (which were pretty specific anyway). Please send me a comment if you need me to recalculate using the leading 100 wine SKU whatsit and I’ll get Professor Google onto it.

 

[1] Miller P et al (2010) ‘The growing popularity of low-carb beers: good marketing or community health risk.’ Medical Journal of Australia Volume 192 (4), found at: https://www.mja.com.au/system/files/issues/192_04_150210/letters_150210_fm-1.pdf