Yep. But I don't think it's reducing hunger pains, it's actually reducing thirst. Hunger pains and thirst are often easily confused (the biochemical signals are very similar, so individuals easily misinterpret them) and that is a big issue: "I'm hungry!" tends to actually mean you are just thirsty, and instead of tackling that properly with some water, the "hungry" person solves their dilemma with a double quarter-pounder.
One would think that it would be relatively easy to coach humans into first responding to "hunger pains" by drinking a cup or two of water, and see if that solves the problem, but you know: humans.