My friend Johanna recently spent a week eating by color. For seven days, her food intake was dictated by the traditional optical spectrum. (Her experiment is first described here; this is the post-week recap.)
Living and digesting by ROYGBIV meant a lot of bluish-purple food, which is unfortunate and sugary. Here's her Blue (Friday) diary:
"BLUE: the absolute worst. I had blueberries all day. And Gatorade. Dinner was this gross blue ice cream I saw at Baskin Robbins. This was so, so gross. Most people tell me they started to worry because they were feeling sick just looking at the photos. Blueberries aside, there is nothing blue that isn't synthetic. And don't try to argue with me here. There are 30 people that each said 'Let me think, I know I can think of something blue for you to eat' and I would respond with 'No. Really. You can't.' Don't say blue potatoes or blue corn chips. This was a photography project, and they do not photograph blue. I hated blue day."