This is hardly a full lifecycle assessment. The assertion is true only for cyclists eating a mad diet and only if: 1. Motorists really do eat less food than c

This is hardly a full lifecycle assessment. The assertion is true only for cyclists eating a mad diet and only if: 1. Motorists really do eat less food than cyclists, controlling for other factors. 2. You only count transit-energy emissions (not construction or recycling or road maintenance or healthcare etc). To my knowledge, there is no evidence that active travel modes are associated with greater calorie consumption. There is plenty of evidence that all kinds of important externalities are worse for any kind of car-travel versus cycling. You can perhaps make an argument based on average lifespan that motoring is better for the environment because it costs more life years per km, but advocating for shorter lives in the name of carbon emissions is not going to be popular (and if so, there are less polluting ways to do it).