This article does a good job of listing the different kinds of nutrients, telling you in what foods these nutrients can be found, and gives the recommended daily allowance for each. Good information provided here, but very basic and a very short read.

I really expected better from the Mayo Clinic. The information is accurate, but there just isn't much of it on this page. I followed the link at the bottom to the article about butter vs. margarine, though. At least I learned something there.

This information may be very basic but I think that is the point here. The Mayo Clinic offers a lot of information and more detail but this was designed to provide details on the basics which is perfect to begin with. The Mayo Clinic provides information to the general public so less is more when you are talking to all peoples. Many diets or nutritional sites/articles will provide more examples and varying details but this would be your starting point for anyone!