This presentation compares Atkins to low carb diet, and 2 others. I found the results absolutely fascinating. You need to be a geek and watch the whole thing to watch this. To sum things up: Net flux is the universal rule, calories in equals calories out. Eat more than you burn and you will gain weight. Burn more than you eat and you will lose weight. In some situations the low carb diet has a distinctive advantage – pre diabetic and insulin resistant people benefit from the low carb diet (makes sense, right?) The quality of the calories you consume do matter. I liked the part about energy density and portion size.