I haven't looked at this particular study so this is just a general observation. When I was looking at many studies in depth fifteen years ago I was amazed to discover just how few researchers every bothered to look into what a low-carb diet, such as Atkins, even was. Yet they would do a study specifically aimed at showing the poor effects of following low-carb diets such as Atkins by having patients on the "low-carb diet" eating 200 g of carbs instead of the U.S. RDA of 300 g a day. And, of course, it was their findings that would get all kinds of media coverage since debunking Atkins was all the rage back then.

It's very hard to find good quality research results that are unbiased and properly done.