Is fruit bad for you?

After following a raw foods diet following the acid/alkaline principles

of people like David Wolfe, Robert Young and Alex Guerrero, I lost 90
pounds within a year. I'm now 15 pounds from my ideal weight. Feels
great! My energy level has tripled. I'm never ill. All my animal and
plant allergies have disappeared. So has my asthma.
The authors above says that the natural sugar in fruit becomes acidic
when broken down. They recommend non-sweet fruits like tomatoes,
avocados and grape fruit.

What's your experiences? Anyone have documentation for or against this
theory?

Hope to get a great debate out of this.

Regards,
Tony