Researchers at Tufts University, Laura Pimpin and Dariush Mozaffarian, in Boston conducted a systematic review and meta-analysis, published in PLOS ONE, to look for correlations between butter and chronic disease. Since views on dietary fat have been changing recently, it should not be surprising if views on butter change as well. Indeed, the conclusions of this research support that butter is more or less neutral, and not linked with chronic disease or mortality.
What did they do to reach their conclusions? They reviewed 9 research studies, which involved well over half a million people, and accounted for 6.5 million person years of follow up. All together, these 9 studies involved approximately 28,271 deaths, 9,783 cases of cardiovascular disease and 23,954 cases of type 2 diabetes development. A meta-analysis of relative risk is what was used to quantify results.
This next point deserves consideration. The amount of butter consumed was standardized across the 9 studies. The average butter intake of the people being studied ranged between only 1/3 of a tablespoon to 3 tablespoons.
Ultimately, the main findings of the study were that this amount of butter is not linked in any way to chronic disease or mortality, and is neutral to health. While the researchers are not calling butter a health food at this time, they feel is should not be demonized. Two final noteworthy points are that other sources of fat may be superior to butter because they are more nutritious, and yet butter may have potential to lower the risk of diabetes.
“Overall, our results suggest that butter should neither be demonized nor considered “back” as a route to good health,” said Mozaffarian. “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.”