Low-carb and low-alcohol beers are marketed as “healthier alternatives” for drinking. Low anything is an easy sales line – like the original, but healthier! But is it really worth it?

Low-carb beers
A standard (375-mililitre) bottle of beer has about nine grams of carbohydrates; the average low-carb beer has about three grams. That’s one-third the carbs, which sounds like a substantial reduction. But it’s worth considering that beer doesn’t contain a terribly high amount of carbs to start with, so the per-bottle savings are about equal to half a slice of bread.

Most people equate carbs with energy, and low-carb beers do have about 25 per cent fewer kilojoules (energy) in them compared to standard brews. But, beer is still a kilojoule-dense beverage option even if it is low carb (most of the energy in beer comes from the alcohol, not the carbs, and low-carb beer has the same amount of alcohol as regular), and excess kilojoule intake leads to weight gain. Overweight and obesity are linked to an increased risk of heart disease, diabetes and many other health issues, so reducing your kilojoule intake can often be a good thing.

One 375-mililitre bottle of standard beer contains about seven per cent of the average recommended daily kilojoule intake, while the low carb has about five per cent. Overindulge in either and the energy intake quickly adds up. While low carb may be a “healthier” option in comparison, don’t let low carb be an excuse to overindulge.

Light beer
Light (low-alcohol) beer is about 2.7 per cent alcohol (compared to 4.6 per cent alcohol in a standard beer) and has the same number of kilojoules as a low-carb beer. Excess alcohol consumption is a risk factor for many diseases, so low-alcohol beer could be better for your liver and health. But, it’s the overall amount of alcohol that matters, not the percentage of alcohol or carbs in the beverage.

The more we drink, the more likely we are to snack, too (late-night kebab, anyone?). So it isn’t just the drinking that contributes to the “beer belly”. More alcohol-free days in your week might help to cut the kilojoules and drop the weight, if that’s your aim.

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Is the swap worth it?
A move to low-carb or light beer, and the carb and energy (kilojoule) savings it may result in, will really only add up if you are already drinking a lot, which, from a health perspective, is not recommended anyway.

If you drink a beer a day then over a year a straight swap to low-carb or low-alcohol saves you just over 62,000 kilojoules of energy – if you do the maths, that’s not even a two-kilogram weight loss over the entire year. The problem with “straight swaps” like this is they can lull us into a false sense of having made a “healthy” choice and stop us from making other more healthy changes.

So, if like most people you prefer the taste of a standard brew and don’t want to pay the “health” mark up, it’s more enjoyable, and just as effective, to cut the number of drinks you consume. Ultimately, beer is never going to be a health food, no matter the marketing, so enjoy, but enjoy responsibly.

Dr Emma Beckett is Broadsheet’s nutrition columnist. A molecular nutritionist with a Ph.D. in Food Science, she is a post-doctoral fellow in the School of Medicine and Public Health at the University of Newcastle. In a world of mixed messages she can be found busting nutrition myths and empowering people to critically assess nutrition information. She tweets at @synapse101.

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