"Even though people who eat more butter generally have worse diets and lifestyles, it seemed to be pretty neutral overall," Laura Pimpin, Ph.D., former postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts, said in a press release. "This suggests that butter may be a 'middle-of-the-road' food: a more healthful choice than sugar or starch, such as the white bread or potato on which butter is commonly spread and which have been linked to higher risk of diabetes and cardiovascular disease; and a worse choice than many margarines and cooking oils -- those rich in healthy fats such as soybean, canola, flaxseed, and extra virgin olive oils -- which would likely lower risk compared with either butter or refined grains, starches, and sugars."
Ultimately, the researchers offer butter lovers an exciting, but cautious, conclusion (emphasis added):
"Overall, our results suggest that butter should neither be demonized nor considered 'back' as a route to good health," Dariush Mozaffarian, M.D., Dr.P.H., and senior author of the study, said. "More research is needed to better understand the observed potential lower risk of diabetes, which has also been suggested in some other studies of dairy fat. This could be real, or due to other factors linked to eating butter -- our study does not prove cause-and-effect."