Not All Studies Are Created Equal

Headlines in the March New York Times announce "Butter is back" because a new study doubts saturated fats are linked to heart disease. While in Nov. of last year, the American Heart Assoc. and the American College of Cardiology issued their statement: "cut saturated fat to half the earlier target level." So, what gives? Look at who did the study and wrote the publication. A study undertaken or reviewed by a commercial entity, as in, someone with something to sell, could just be shaky science. A less biased publication would come from a university study, non-profit organization, or a government agency not affiliated with a for profit organization. Though fraud may not be involved, the methodology or variables involved would produce different results.
 The meta-analysis in question included a trial that fed people a margarine high in trans fat to compare to a group of people who were given butter. Trans fats, being the root of all evil, raised the LDL of the margarine group, so it was deemed that the folks in the "polyunsaturated" group had a 19% higher risk over those who ate butter  (the "saturated " group). The error was omitted from the final report, so it did not make the headlines.
With so much controversy over what is good to eat and what is not, it is no wonder Americans are confused to the point of apathy. Look beyond the headlines. It is safe to assume that our billion dollar food industry has much riding on their advertising campaigns, and is not above assembling scientists sympathetic to their cause and encouraging them to make statements on their behalf.
~ Prof. Martijn Katan, University of Amsterdam, 2014