The truth about protein: how much should we really be eating?

First came the dubious diet advice.

In 1877, Carl von Voit, one of German chemist Justus von Liebig’s protégés, published an influential recommendation that working men required 118 grams of protein per day. The recommendation wasn’t based on physiological research; Voit simply asked what men in Munich would like to eat if they could eat anything. This was another “example of a standard that the public believed to be authoritative and derived from the scientific work of an expert although, in fact, the standard and the work had little or no connection,” wrote nutrition scientist Kenneth Carpenter in his comprehensive Protein and Energy.