If a guy starts looking a little chesty, he might blame it on eating a few extra cheeseburgers or skipping sessions at the gym. But not Jeremy Piven. The man who claimed sushi gave him mercury poisoning, is now saying that soy milk gave him man boobs.

Specifically, Piven blames the fact that he used the dairy substitute on his cereal for his "moobs." He told BANG Media International (via Celebedge), "I was the guy that dabbled in soya milk, but now I've found out soya milk has enough estrogen for me to grow breasts; I had to put the soya milk down. It was a very confusing time."

A very quick search on the Internet will reveal tons of conflicting information regarding soy. Soy is great! Soy is the worst! So what are you supposed to believe?

We went to an expert for the answer. Jill Hamilton-Reeves, assistant professor of family, consumer and nutritional sciences at St. Catherine University in Minn., released a study this summer about the effects of soy on the reproductive hormones in men, and she took a moment to talk to That's Fit about Piven's claim.

Piven was drinking about 12 cups (about 3/4 of a gallon) of soy milk a day, Hamilton-Reeves learned from Mark Messina (a soy guru, if you will). "That means he was taking in approximately 360 mg of isoflavones a day," she says. "And isoflavones are what people generally believe to be responsible for any effects in male reproductive hormones."

(We'd like to point out that, not only are we looking at a large intake of isoflavones, but calories in general -- that's a lot of soy milk!)

"Usually, studies only go as high as 150 mg of isoflavones a day," Hamilton-Reeves says. "And a reasonable intake would normally be about 100 mg a day, which is four full servings of soy." Although most studies do not cover Piven's level of consumption, she still said that his claim was not supported by the wide range of evidence that is out there.

Not only did her study find that soy products didn't affect reproductive hormones in men, but numerous other studies have as well. "Soy has been studied extensively for 20 years," she says, "and we haven't found man boobs yet."

Everything in moderation, even if it has some health benefits.