Is the American-government-endoursed definition of a healthy/balanced diet based more heavily on science or on commercial merketing campaigns?

Much of our understanding of nutrition comes from marketing and a need to boost consumption of certain commertial products. Nutrition is also a very new science. So what are the facts? Do we really need bacon and eggs and pancakes and fruit and milk and orange juice every morning to be healthy, or would an apple and a piece of toast have been enough? Are the government-set nutrition standards even acheivable without supplements if shopping at a traditional grocery store?

I would like to research this topic because I personally strive to eat healthy on a daily basis. Over the past year or so I have begun to question my own ideas about nutrition and the government’s ideas about nutrition just as I challenge ideas in other aspects of my life. Since the FDA has approved small amounts of formaldehyde and sodium cayanide for human consumption (it’s an ingredient in Mountain Dew) I feel like maybe my idea of “good to eat” might be different from the government’s.