How to study nutrition?

Is there a serious, independent study published in a prominent, peer-reviewed scientific journal that shows that life expectancy and healthiness depend on nutrition?

• For example that you can increase your life span by  eating food that is considered as healthy nowadays. Also vegetarians or vegans don't life longer then normal people if they don't smoke. I want only serious journals with peer-review which are not influenced by any company that  deals with nutrition, this is very important ! Or you can at least make sure that the study is really reliable. My own opinion on that is that it is less important what you eat, but that you do sport on a regular basis. That's why I thought of that question if it helps anyone.

• Answer:

  Many, many studies. I will mention just a few recent that got some publicity. There was one study comparing low fat diet with Mediterranean diet, the latter was associated with superior health parameters. Another study recently showed that regular consumption of nuts was associated with better cardiovascular health. Yet another study demonstrated the importance of breakfast for academic achievements. There are many professional medical journals dedicated to the effects of nutrition. Finding this information is not too difficult nowadays, but I will drop several references just because I promised to. References: http://www.nejm.org/doi/full/10.1056/NEJMoa1307352 http://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0079324 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3275817/