They make a lot of all natural products. Right now I'm using their fennel, myrrh and propolis toothpaste. Tis fluoride free and tastes pretty good.
I have the crappiest teeth. I'm only in my mid 20s and I'll probably have dentures by my 40s unless a miracle happens or I win the lottery. I brush every freaking day but it makes no difference, my teeth just fall apart. I think it's genetic because both my parents and my siblings all have crappy teeth. Anyway, I've always used fluoride toothpaste because I figured my teeth are so messed up I don't want to do anything to make it worse, but due to the persuasive powers of certain people decided to take a plunge and use this Tom's of Maine toothpaste sans the fluoride. I have uber sensitive teeth though, due to all the work that's been done on them, so I always use toothpaste for sensitive teeth. The only sensitive teeth paste that Tom makes is wintergreen flavor and I absolutely loathe mint and will not use a mint flavored toothpaste so don't know what I'm going to do. If anyone knows of some secret magical product that's supposed to prevent the decay of inferior teeth such as mine, please do share.
When I was a child a dentist said he thougt I must have an abnormally high level of acidic matter in my saliva which basically eats away at my teeth and causes mass deterioration. However, all the dentists I've seen as an adult ever suggest, after pooh-poohing this acidic theory, is for to let them write me a prescription for a toothpaste with an extremely high amount of fluoride. Needless to say, I never acquiesced. How does one counteract acidic saliva? Seriously, my teeth are the bane of my existence. They're cursed, methinks 
"A dream has power to poison sleep"
-Percy Bysshe Shelley