You probably brush your teeth and visit a dentist, so you do appear to believe man can improve on nature. It's not natural to brush teeth or visit a dentist - those are very recent human behaviours and technologies in the grand scheme of things. Many things you do aren't natural, but that doesn't mean they're unhealthy or bad, necessarily.
Speaking of natural and meat, if you season your meat, that's not natural. If you cook it, that's not natural. If you didn't hunt and kill it yourself, that's not natural. Just about nothing about your "meat" is natural today.