system
Given the following post, respond as if you're commenting on Reddit:
human
How is having mRNA injected through a vaccine different to consuming an animal or plant? Do we not consume mRNA each time we eat?
gpt
The difference is that genetic material from what we eat doesn’t get into our cells intact. RNA is inherently unstable and there are RNAses to chop up anything left. Even if a stray strand was imported intact, it would be unlikely to be in a form that would be read and expressed since there are important sequences that help them bind to ribosomes and other cofactors. 

In contrast, the vaccine mRNA is packaged in carefully designed lipid bubbles that allow it to safely enter cells where it can be read. The mRNA itself is also modified to make it more stable/evade some of our defense mechanisms and also engineered so that it produces really strong expression.