"He cut off her lips and ate them," Swedish daily Aftonbladet quoted an unnamed source close to the case as saying.
"He doesn't seem to regret anything. He thinks she is the one who has offended him," the source added.
The man, an associate professor at Sweden's prestigious Karolinska Institute whose name was not given, was reportedly being held on suspicion of attempted murder, according to the report.
"She is of course not doing well, neither psychologically nor physically," the woman's lawyer Ingela Ekman Hessius told Aftonbladet.
The lawyer told the paper her client had suffered "very serious injuries. The doctors have not yet said whether they can fix this or not".
The attacker, who has now been ordered to undergo a psychiatric evaluation, reportedly had several children from a first marriage, which had ended only weeks before he married his current wife, a much younger woman.
According to Aftonbladet, he had recently begun to suspect that she was having an affair and had allegedly decided to punish her by disfiguring her.
"He didn't want the lips to be able to be sewn back on," the unnamed source said, explaining why he had eaten them.