I eat healthily and get spots, despite doing lots of exercise and drinking massive amounts of water.
I can't get rid of spots, and wouldn't prefer the side effects of the prescription medicines, but I've found they go down considerably when:
I drink no milk. Greasy food/dark chocolate(not dairy) don't seem to make any difference
Stress - Around results day my spots were terribly bad, they've now cleared up.
My current tip is to use savlon if you get recurring spots. I kept getting them just under my jawbone at the back, and wiping savlon over them has since cleared them completely - although it hasn't worked so well on the rest of my face, and I'm reluctant to completely coat myself in the stuff!
Basically, if you don't care about them too much, so get less stressed about them, it almost helps itself.