I've written a lot about my frustration with the failure of the calories in/calories out equation in my life. I think at this point I've gained back almost all the weight I lost 8 years ago, a big chunk of that over the past 2 years, but I haven't really changed that much in my life. I have periods of eating healthy, and periods of not eating so healthy. I have periods of working out regularly, and then working out irregularly. After years of tracking my calories, I have a pretty good idea of my average calories per day, and yet I don't lose weight, despite all of the various equations telling me that I should be dropping weight, no problem.
Today I read Tom Naughton's latest post and was struck again by the ridiculousness of our standard nutritional guidelines and the expectation that every person should fit into a tidy little height/weight box. Basically, Tom writes about his 2 dogs, who have been raised together, eating the same food, yet one is 18 pounds heavier, and much more muscular than the other. In reality, it's not just calories in/calories out. Weight and body shape is created by a complicated cocktail of calories, exercise, genetics and hormones. The things we eat do impact how we look and what we weigh, but not in the simplistic manner that we've been taught.
Personally, I feel best when I exercise regularly and when I eat a lower carb diet, particularly excluding wheat. I'm trying to make peace with the fact that despite all that I do, while I feel good, have low blood pressure and a low resting heart rate, I will most likely never be thin.
(By the way, if you haven't seen Tom's movie Fat Head, I cannot recommend it enough. Jason the Scientist confirms that the science is right on.)