The first "official studies" were produced this year, 30+ years after the diet's phenomenal introduction. Maybe they'll do a follow up study in another 30+ years. Personally, I won't be waiting around to find out, eating a low fat diet and developing diabetes and heart disease. Thanks, but no thanks.
The correlation between the increase in per capita consumption of carbohydrates (from 30 to 40 percent over a ten year period) and the increase in cases of diabetes and heart disease per capita is enough to convince me that low fat dieting is an unprecedented medical-field-generated disaster.
Besides strong opinions, I have seen no hard data indicating any problems with low-carb diets.