No, 500 is too low...
Source:
http://www.iom.edu/Object.File/Master/20/004/0.pdf as linked from
DRI Tables : Dietary Guidance : Food and Nutrition Information Center
It varies by age, but it looked like the minimum was largely 1500, and certainly never less than 1000. Note I think the units in the table are grams, so divide by 1000. The maximums were between 2-2.5 G.