If you have the chance, please watch Seaspiracy on Netflix.
It does use some shocking footage to get its point across, but the science is sound.
For example, fish don’t produce the Omega-3 oils that so many nutritionist and scientist recommend we supplement in out diets… it comes from sea plants that they eat. We would get better and higher quantities from the plants.
AND we wouldn’t be contributing to the massive overfishing of the oceans.