My environmental studies prof did an experiment cycling and getting the bus to university on both the amounnt of money spent and energy consumed. He found that

My environmental studies prof did an experiment cycling and getting the bus to university on both the amounnt of money spent and energy consumed. He found that he would spend more if cycling than the bus fare on food to keep the same energy input equal. People also generally cannot sustain eating less continually but obviously there's a health benefit from some changes. The ecosystem approach to food energy and carbon brings some surprising convulsions too. For example wrapping and selling fruit in plastic bags is better than buying them loose. This doesn't make sense unless you think about the whole picture. I suspect that the recent HN craze for indiscriminate feel good tree planting is also ecologically and sustainably suspect if looked at holistically.