One recent trend in Japan is zero sugar beer, which is interesting for a number of reasons:
1) it is not really "beer", because the malt content is kept low enough to be classified as "happoshu" under the law, and is therefore subject to a lower tax rate. ("Happoshu" is a good deal cheaper than "beer", but cannot be labeled "beer".)
2) production processes are used which result in all or most of the sugars being consumed by the yeast, before the yeast are killed. If there are fewer than 0.5 grams of sugar per 100 ml, it can be labeled as zero under the law. So there actually are sugars in all of these "zero sugar beers". In fact, carbohydrates (for which the definition is broader) are not addressed by this labeling at all.
3) what is the marketing angle for these beers (I will call them beers, at least in this post)? Being able to put a big zero on the label is most likely the main attraction. Some customers will, no doubt, assume the zero refers to calories. The beer companies are unlikely to go to great lengths to disabuse these customers of their mistake. But for customers who do know what is being referred to, and Japanese consumers are relatively well informed, these beers certainly do hold an attraction - mainly for people concerned about high blood sugar and diabetes. These products should also be attractive to people on low carbohydrate Atkins-type diets.
4) the sugar taste has to be compensated for and the individual formulations differ, some including artificial sweeteners.
5) these are beers where both the malt and sugar contents are being held very low, a challenge for a product which is produced from a limited number of ingredients. Beer is a complex chemical mixture, but it starts out from a deceptively simple combination of ingredients. (Granted, this is not Germany and even the German law has been revised, but under the "German Beer Purity Law" only water, barley and hops were allowed in the production of "beer".)
I plan on revisiting many of the above points in the future.
The three zero sugar beers shown in the picture are Asahi Free Style (Toshitsu Zero), Suntory Zero-Nama and Kirin Zero. All varieties shown are 500 ml cans of happoshu-type beers.