there are health risks related to not eating enough dairy, too.
There are health risks associated with everything... It's how you balance them up. For example I don't smoke, but most of my working life I worked shifts which screws you up by not giving your body enough/consistent down time. The reckoning is that it literally takes years off your life. Anyhow I stopped doing those when I just physically couldn't do it any more. I actually quite liked them and there were many benefits, not just financially, you got lots of time off and it was nice to be off when everyone was at work. It totally freaked me out just how busy the world was when I came off shift...
Likewise meat. As with so many other things, it's probably bad for me, but it's very, very tasty. Rabbit food simply isn't. As I enjoy food I accept the risks in order to gain pleasure from eating.
I look at life like this (having had one of my best friends die very young), you can pretty much pop your clogs at any time. Freak accident on the way to work, fit blokes even have heart attacks in their 20's these days playing footy. Life really is too short not to enjoy it as much as you can while you're fit and healthy enough to do it.
My father regrets not buying a sports car and being a tight arse all his life. Pancreatitis nearly killed him and caused him to re-evaluate his philosophy. Sadly his hips and back are so knackered now he can't drive the car he always dreamed of and now actively encourages me to do it now while I can (but still be sensible when it comes to planning for the future). It's balance essentially.
On to the global warming thing.
I'm sure it'll sound selfish to the people that think I'm killing the planet in one way or another. But look at it this way; we're part of this planet's eco-system for better or for worse (mainly the latter) and yes, what we do absolutely has a knock on effect on a global scale.
There is irrefutable proof that the planet is warming as there's no denying that the ice caps are melting. Relatively speaking we're still coming out of an ice age (thinking of this on a planetary scale, not a human one). Will we have impact on that? Almost certainly. Are we causing it? That simply cannot be proven one way or the other. Anything published stating 'facts' on this are more often that not best guesses portrayed as facts to push a political agenda. Is it a bad thing on a planetary scale? Who knows!
As such it cannot be proven that cows farting is causing the planet to melt... If so, using my dodgy science, vegitarians (as cows also are) fart more and are also causing global warming. Eat meat (vegitarians) and save the planet!