What are 'beni-koji' products linked to Japan deaths?

TOKYO -- Deaths and hospitalizations have been reported among a number of people who consumed a mold-based supplement manufactured by a Japanese pharmaceutical company.

Osaka-based Kobayashi Pharmaceutical Co.'s "Beni-koji choleste-help" contains "beni-koji," a variety of koji mold-cultured foods consumed since long ago in countries including China, Taiwan and Japan. Beni-koji is made by culturing Monascus mold species on grains such as rice. Popular for its natural red color, the ingredient is found in "tofuyo" Okinawan-style fermented tofu, as well as in a variety of Chinese rice wine and other dishes.

According to Kagoshima University associate professor Yumiko Yoshizaki, an expert on the study of fermented foods, Japanese researchers discovered an ingredient found to lower cholesterol, called "monacolin K," from the mold in the 1970s. In recent years, this has garnered attention as an ingredient in health supplements.

However, some Monascus species produce citrinin, a toxic substance which is thought to bring about kidney disorders. Kobayashi Pharmaceutical's product is made using a type of the mold species that does not produce this mycotoxin, and a product analysis performed after the issue came to light did not confirm the presence of any citrinin.

According to the Food Safety Commission of Japan, reports of health problems suspected to be caused by consumption of supplements derived from beni-koji led the European Union in 2014 to set standard values for citrinin created by the molds in supplements.

In France, people are cautioned to consult a doctor before consuming beni-koji products, and in Switzerland, the sale of foods and medicines containing them is banned.

On the other hand, Yoshizaki called for consumers to remain calm, insisting, "Beni-koji has been rooted in Japanese food culture since long before we knew toxins were produced," and adding, "There's no need to be overly concerned about products other than this supplement as long as it's not taken in excess."

(Japanese original by Asako Kuroda, Lifestyle, Science & Environment News Department)