Unless you are a chemist, it is probably the latter. And yet, most drinking guidelines presume the former. Regulations in some countries have treated consumers like human calculators, expecting them to navigate a world of “units” and “standard drinks” that exist nowhere outside of a laboratory.

Recently announced U.S. Dietary Guidelines made a notable shift away from this approach. They dropped daily drink recommendations, effectively abandoning the concept of the “standard drink”. This move allows for a simpler message: adults who choose to drink should do so moderately.

As global policymakers consider how to best support moderation, a key question to grapple with is whether guidelines are fit for purpose in the real world.

The myth of the standard drink

The “standard drink” has always been a fiction that assumes a level of precision and consistency that may be found in a lab but not at a dinner party.

Glass sizes vary. Alcohol strengths vary. Wine is often topped up mid-glass. Hard liquor is free-poured at home and in many bars. Most of the world’s top-selling cocktails, like a Negroni, Martini, or Old Fashioned, are often 20%–30% Alcohol by Volume (ABV) or more. Why are consumers being taught that “a drink is a drink” when there are stark differences in how much alcohol different drinks can contain?

This challenge is compounded because a “standard drink” varies across borders. A unit of alcohol in Vienna is double the size of one in Madrid. If policymakers and scientists cannot settle on a common definition, it is unrealistic to expect consumers to translate these abstractions into everyday behaviour.

And, around the world, alcohol is embedded in different cultures in a variety of different ways, which cannot be reduced into a single technical framework—from Japanese sake traditions to Polish vodka customs to Brazilian beer culture. Instead, policy should focus on common sense and functional health literacy.

From mental maths to behaviour shifts

Of course, anything with alcohol can be abused, but not all drinking patterns carry the same risk. The highest risk patterns generally involve drinking high–strength products quickly.

Stronger guidance should therefore focus on promoting patterns that are “low and slow”, encouraging consumers to choose lower-strength options and to pace themselves.

This “low and slow” approach is not just common sense; it is backed by research. A comprehensive World Health Organization (WHO) review of alcohol policies in Russia concluded that shifting consumption away from high-strength liquor was directly associated with improving multiple public health indicators (WHO Europe, 2019).

Beer fits the “low and slow” drinking pattern naturally. It is lower in alcohol by volume than other categories and the volume of liquid provides a built-in pacing mechanism. And the beer industry’s use of single-serve packaging removes the guesswork common with free-poured drinks. A consumer drinking a 25cl beer at 5% ABV knows exactly what they are consuming without needing a calculator.

At the same time, brewers are meeting a significant and growing consumer demand for lower- and no-alcohol beers. The market for lower- and no-alcohol products grew by more than 7% in 10 key global markets in 2022, with beer making up much of this category (IWSR, 2022).

This growing market has a real impact on behaviour, with a study in the UK finding one in five consumers reported their weekly alcohol consumption decreased after they started drinking lower- and no-alcohol alternatives (Portman Group, 2022).

From theory to reality

Moderation tends to happen through small, realistic choices. As policymakers consider how best to promote moderation, they should focus on closing the gap between theory and practice by looking to proven, evidence-based strategies.

Experts have long called for regulations that differentiate by beverage type and alcohol content—a practice that is less restrictive for beverages with less concentrated alcohol like beer (Rehm et al., 2019).

Around the world, there are governments already leading the way. Many OECD members, for example, apply lower excise tax rates to beer than to hard liquor and offer even lower rates for lower- and no-alcohol options, effectively nudging both producers and consumers toward moderation (OECD, 2020).

Moderation is not a maths problem to solve, but a behaviour to support. If we want to promote moderation, it’s time to rethink the “standard drink.”

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