Thought this was c/shittyasklemmy. It's not, so here's an earnest response. I'm from the US, but have spent a bunch of time living outside of the country. Every guy I know usually poops daily, but a lot of women only poop every couple of days. It doesn't have anything to do with the cold.
Fun somewhat related story time. I once had a colleague travel to the US from South East Asia. He went to our boss a few days into the trip and said he needed to go to the hospital. My boss eventually convinced him to explain the problem. His poop was a solid mass instead of liquid. Dude had never had solid shit before. It's possible an anecdote like this is what gave your teacher that idea.
The fields being covered aren't being used to grow food for living things, they're being used to grow food for cars. 40% of corn grown in the US is used to make ethanol to dilute gasoline.