Anthony Bourdain is putting Paula Deen ON BLAST -- mocking the butter-loving chef for poisoning Americans with unhealthy food ... and now trying to profit off of their illness.

In an ultra-transparent Twitter attack -- Bourdain wrote, "Thinking of getting into the leg-breaking business, so I can profitably sell crutches later."

The "Kitchen Confidential" author is presumably pissed that Deen -- who built an empire off her high-fat, high-sugar recipes -- announced she has diabetes ... and subsequently revealed she's become a paid spokeswoman for a diabetes medication.

There are reports ... Deen knew about her diabetes for years -- but continued to hock her recipes on her Food Network cooking show, while secretly negotiating the endorsement deal.

Obviously, Bourdain sees a serious conflict of interest in Deen's behavior.

And it's not the first time Bourdain went for the jugular with Paula -- just last year, he called Deen the "most dangerous person to America" who's "proud of the fact that her food is f**king bad for you."