Please watch What The Health and Cowspiracy. Veganism is the ultimate rational decision.
Aside from eating meat and dairy being awful for your health and costing health services millions, animal agriculture is the leading cause of climate change - bigger than all the cars, planes and trains put together. I know this isn't what you want to hear - believe me. When I first found it about this stuff and the person I'd watched Cowspiracy with said 'we have to go vegan, don't we?' I was like '...do we though?' But to be honest, the answer was yes. It might not be easy at first but it's the only rational (and moral) choice. You live on the planet, you should help look after it.
Lol. This is exactly what I'm talking about. All the toxic emissions of trains, planes and cars put together huh? Where are your numbers to back your strong claims up? The problem isn't us eating meat it is our lavish way of wasting food and energy. Let's get real. There is no way we will all become vegan. That's just never going to happen and we don't have to. We just need to fix the way how we treat food and stop wasting loads of food and water. My mother went to a local grocery store 'Aldi' and she asked how much of their products they threw away. The answer was 30%. 30 f*cling procent. That's your problem right there and veganism isn't going to change that.