too bad they are not as rigorous with the food we eat. One example is that they don't even have the resources to check if the food manufacturers claims are true (you can't be sure what type of fish you eat nowadays).
(The finance sector is even much worse than the FDA in this regard---for example Bernie Madoff was regulated, leading people to think their money was safe with him---but in some ways, the FDA is just as bad.)
Of course it can help, some. I'm not going to deny the obvious. But it's highly imperfect, and it often hurts.