Why would eggs, for which there isn't a chemical formula, nor a standard preparation, be easier to study? What even does "good for you" mean?
Don't get confused between mass-media popular "science" and things science can actually do - like measure whether a dozen eggs a day will raise your LDL and HDL (cholesterol) and cause heart disease - and drawing wild conclusions (especially right now) from pre-print articles that are used to sell magazine articles to use as justification to eat chocolate and drink wine under the guise of "it's good for you".
Don't get confused between mass-media popular "science" and things science can actually do - like measure whether a dozen eggs a day will raise your LDL and HDL (cholesterol) and cause heart disease - and drawing wild conclusions (especially right now) from pre-print articles that are used to sell magazine articles to use as justification to eat chocolate and drink wine under the guise of "it's good for you".