Comment by bregma

4 oz (a quarter pound) is 100 g or an amount about the size of the palm of your hand -- a single serving. It's not a small portion, it's recommended standard portion.

If you were following the old food guide in use for the last 20 years -- the one that replaces the food pyramid -- you'd see that 100 g is about a quarter of your plate. The old food guide could be summed up as "a quarter of your plate should be protein, a quarter carbs, and half fruits and vegetables". Real simple, so simple anyone could understand it. Although I have been presented with evidence recently that there are some who can not.