"Sadly, this is the same reasoning that allows people to believe all sorts of demonstrably untrue things: that Obama is a Muslim, that 9/11 was an inside job, that Iraq had WMDs. "
Yeah, confirmation bias is why we have lots of things, I can certainly catch myself demonstrating it at times. I'll bet we all can. But I'd point out that questioning results is not necessarily dismissing them outright. After all, isn't that what a good scientist does, and what advances science? You just need to question the results you like as fervently as you question those you don't like. So I think we agree.
But to the matter at hand, I'm not sure one can easily define "premature death." I have an issue with that phrase itself. Our bodies break down, we die. Something, at some time, is going to break down and we're going to die. We can use average life spans, I guess, to judge certain things against, but our bodies, while sharing basic characteristics and genes, are also very unique.
I have no doubt, actually, that red meat can help something break down earlier than it might otherwise. But then, I think that anything we put into our bodies can help something break down, while at the same time helping other parts of our complicated system thrive. The difficulty becomes balancing whatever positive effects against whatever negative effects, taking in to account intangibles like pleasure and enjoyment and such. It could drive you batty.
So I'm with some of the other posters - most things in moderation, stay active, and above all, be happy. I think the last thing does more to ensure an enjoyable long life than just about anything else.
And as far as premature death: as I've said many times before, breathing ain't living. I'm not here to breathe as long as I can, I'm here to live as long as I can. And only I can define living for me - not some politician, not some religion, not some health advocate, not some special interest group, etc. etc. So when I'm no longer living, by my definition, I'll do whatever is necessary to ensure I stop breathing as well, prematurely or not.