I was in Brazil in 1995 and one of the Brazilian girls I was eating with mentioned she is not going to eat the pasta / carbs because she is trying to lose weight. I thought she had no idea what she was talking about, what she needed to do was cut out the fat. Turns out I was wrong.
Not really, it turns out the carbs from glucose (pasta) are actually pretty good for you. If she also cut the carbs by removing fruit juice and soda from her diet, then it would have been the right approach.
For more info, watch the Lustig video already linked in this thread.
Apparently combining carbs with fat is conducive to fat accumulation. So, avoiding that pasta with olive oil or butter is a good idea if you want to loose weight.
