Japanese firm Kobayashi Pharmaceutical says some people have developed illnesses after taking one of its health food products. It is voluntarily recalling all products containing "beni-koji," or red yeast rice.

The Osaka-based company says it received reports in January that those who had taken a product named "Beni-koji choleste-help" developed kidney disease or other illnesses.

Company officials say 13 users have complained of bad physical conditions, and that six of them have been hospitalized, with dialysis used on at least one.

They note that an analysis has found the product may have contained ingredients that the maker had not intended to include.

The company says it is voluntarily recalling the product, along with two other items also containing "beni-koji". The two others are "Natto-kinase sara-sara tsubu gold" and "Naishi-help plus cholesterol." The company is calling on people not to take them.

The officials say they began sales of the "Beni-koji choleste-help" in 2021, with the expectation it would help lower cholesterol or blood pressure levels. They have sold more than 1 million packages.