Changing nutritional guidelines

On our [pilgrimage to the Kwik-E-Mart](http://www.flickr.com/photos/bobman/841391155/) today, I was enticed into buying and eating a neon pink donut and a neon blue Slushee. I downed those on the skateboard ride back to work (yep, work), and almost immediately regretted it. My body just couldn’t handle the sugar, which took me on a wild ride from hyperactive to headache in less than 10 minutes, and left my throat feeling like a cold was coming on.

I used to ingest just about any food with no problems. Now that I’m taking care of my body and watching closely what I eat, I no longer have that tolerance. Is that because of my normal carefulness? Or am I just getting old?