Yeah, exactly. If it's all about what you obsessively exclude from your diet, rather than what you include, then you've got a purity cult (and/or a set-up for eating disorders).

I've found through trial-and-error that my body does seem to run best on lots of meat, fish, fruit, nuts and vegetables, with everything else on the side; it makes a significant difference to my energy levels.

But my body is also very happy with Greek yoghurt for breakfast, and I need to eat high GI-foods like rice and potatoes to recover after climbing or I fall down go boom. The heavens don't fall if I put beans in my tuna salad, the oatmeal in black pudding is not ev0l Neolithic poison, and the occasional chocolate brownie is good for the soul.