This is probably the wrong section for this but I wasn't sure where it belonged. Over the weekend I had some free time to read and found a great study with the full text available.
Here is a great meta study done last year. The full text is available and isn't too tough to read.
Clicky
Here is a quote from the study's author -
"Data from meta-analyses of dietary intervention trials suggest that some weight-loss diets, such as low-carbohydrate diets, low-GI/GL diets, and the Mediterranean diet, might be alternatives to conventional low-fat diets, especially for short-term weight loss, but have great variability of long-term effects. Moreover, the difference in weight loss among these diets is only 1–2 kg or less, which appears to be of little clinical significance. Thus, overweight and obese people can choose many different weight-loss diets
on the basis of their personal preferences."
In other words, there are many ways to lose weight and people can choose from them based on which one they prefer to follow.
Crazy right?