Anyone that actually pays attention to reporting on the latest nutrition studies regarding eggs, wine, vegetables, or anything else concerning our diets knows that the “studies” are at best correlative. This simply means that someone did something and it just so happens that something else happened either at the same time or shortly thereafter. It does not mean that one caused the other. Other than a good conversation starter they are largely worthless.
Quite frankly, probably not. Nutrition research tends to be unreliable because nearly all of it is based on observational studies, which are imprecise, have no controls, and don’t follow an experimental method. As nutrition-research critics Edward Archer and Carl Lavie have put it, “’Nutrition’ is now a degenerating research paradigm in which scientifically illiterate methods, meaningless data, and consensus-driven censorship dominate the empirical landscape.”The Wire
Other nutrition research critics, such as John Ioannidis of Stanford University, have been similarly scathing in their commentary. They point out that observational nutrition studies are essentially just surveys: Researchers ask a group of study participants — a cohort — what they eat and how often, then they track the cohort over time to see what, if any, health conditions the study participants develop.