If you still interested after watching these documentaries, you can still watch more: Forks over Knives, Food Matters, Fat sick and nearly dead, or you can find many more on google or netflix.
To take real action you can start eating healthy! Or I recommend to read the bestseller book Clean by Alejandro Junger.
Eat healthy (but healthy!), do exercise, sleep well and do what you like, for me these are essential nutrients. Make a real effort to prioritize these on the long term, you will be thankful and pleased later!