Beer wouldn't have bee 0.5% historically. Historical recipes where they survive are pretty much exclusively much stronger than this. Moreover a beer at 0.5% wil

Beer wouldn't have bee 0.5% historically. Historical recipes where they survive are pretty much exclusively much stronger than this. Moreover a beer at 0.5% will spoil in basically a small number of days, unless it's heavily soured which isn't described in historical sources. Table beer of that strength, while it exists wouldn't be very good as beer. It's a real art to produce a beer that weak that tastes good at all. Moreover manual laborers in fields were drinking beer for calories as much as for hydration, and any beer with a significant calorie count, say 200 will be in the range of 4%. Pre-modern brewing didn't have precise fermentation controls.