Hiring the right people is likely to be more productive than hiring more. The FDA has a "revolving door" problem with the industries it is supposed to be regulating.

From a NY Times editorial on their poor response to a recent issue with supplements:

Much of the responsibility for the F.D.A.’s sluggish response must fall on Dr. Daniel Fabricant, who left a senior position at the Natural Products Association, a trade group for supplement makers and sellers, to head the F.D.A.’s division of dietary supplement programs in early 2011 and who jumped back to the trade association as its chief executive in the spring of 2014. He has been succeeded at the F.D.A. by several acting directors; the current one is Cara Welch, from the same trade group. Both dragged their feet on BMPEA. [1]

[1] http://www.nytimes.com/2015/04/13/opinion/conflicts-of-inter...