Oxymoron?

Is it strange that as I'm reading my dosage book which is talking about new ways to treat previously incurable cancers, I'm thinking about how many more lives that saves, which means more resources, which means overpopulation, which could eventually mean the destruction of the human race as we use up nonrenewable sources & turn against one another (provided we don't develop the technology to find other sustainable sources)?

^ Run on sentence at its finest.

But really, I wonder how many diseases & conditions exist because we as a human race have interrupted natural selection. We have the capacity to delay/fight off death which is great, I know I'm personally grateful for the technology that exists today (& maybe w/o it, I wouldn't be around to write about it). But, I'm curious to the degree of some of our diseases & if their existence/extent is because we 'saved' individuals who should have died to reproduce & pass along their faulty genes.

I guess that second part didn't really go into world overpopulation etc but that's what I was really getting that. Is it ironic that I'm thinking about this stuff when I'm studying for a profession meant to save people's lives through the use of drug therapies? Hmm.