Though I am a libertarian I am not unwilling to compromise. In exchange for limits on the federal government I would accept state's powers to regulate such as you suggested.
In that way, Americans could vote with their feet to a state or locality most agreeable to their way of life. You could go somewhere that vitamins are regulated, I could go someplace they are not. The "laboratories of democracy" would be the judge of our actions.
Come to think of it, that's precisely how our country was set up. Too bad we've become 'smarter' than that!
Now that taxes here in Central Texas are as high as they are, and going higher, my wife and I are "voting with our feet" and moving back to Minnesota. Not the only reason, but damn... who'da thunk it that TEXAS would be more socialized the MINNESOTA?