This low-carb thing is really something...the way I see it (and I see it all day everyday from training people for a living) is, everyone metabolizes DIFFERENTLY, yet, we all have the same, basic machinery. I think you have to figure out for yourself HOW you metabolize. It's the old GIGO formula: garbage in/garbage out. What you take in on a daily basis is what you should burn on a daily basis. If you are very active on Monday and do nothing on Tuesday, adjust your intake and balance the meals accordingly. Burn what you use and use good fuel. You've body will tell you whether bread bloats you or beer floats you!

I could tell you all stories, reference diets, books, ect all day long, but, the bottom line is always the same; if you leave out a food group, you'll eventually pay the price. If you eat more than you burn, you'll gain weight. Cutting back too far on carbs will eventually lead to the brain getting fuzzy, the muscles aches, less energy ect.

40/30/30 plans are a great way to balance meals and get your needs met...as far as celebs endorsing diets, that's been going on FOREVER and I avoid them like the plague!
Terry