[drdo]

The problem is that doctor, dietitian, or nutritionist don't even agree with each other.

Also, have you actually checked what the FDA nutritional recommendations are? They are really terrible advice that goes against actual science.

[dgallagher]

The problem is that doctor, dietitian, or nutritionist don't even agree with each other.

Look above for another question I answered, similar to this one, which I posted shortly after you posted yours. :)

Also, have you actually checked what the FDA nutritional recommendations are? They are really terrible advice that goes against actual science.

Any examples?

I think you meant USDA nutritional recommendations:

http://www.cnpp.usda.gov/DGAs2010-DGACReport.htm

In my root comment, I meant regulation of nutritional supplements (which is handled by the FDA). This is different than dietary recommendations (e.g. what quantity of vitamins/minerals to eat).

I'm not aware of any problems there are with the USDA's nutritional recommendations, though I'm sure there are some here and there (please share, I'd love to know!). It wouldn't be fair to discredit the entire document if there is an error, however.

It's a living document too, being updated every few years (the 2005 version should be replaced with the 2010 version soon). As more studies are done and more is learned about nutrition and humans, it gets revised.