Author(s)

Yukiko Kato^1*, Masaya Kanayama¹, Shu Yanai², Hajime Nozawa², Osamu Kanauchi¹, Satoru Suzuki³

¹Research Laboratories for Health Science & Food Technologies, Kirin Co., Ltd., Tokyo, Japan.
²Central Laboratories for Key Technologies, Kirin Co., Ltd., Tokyo, Japan.
³Shinagawa Season Terrace Health Care Clinic, Tokyo, Japan.

Background/Aims: Administration of a lactic acid bacterial strain, Lactococcus lactis subsp. lactis JCM 5805 (LC-Plasma), is reported to prevent viral infection via activation of plasmacytoid dendritic cells in mouse and human studies. As it is assumed that LC-Plasma is taken in excess when it is commercially provided as a supplement, we conducted a trial using capsules to give 250 mg LC-Plasma (5 times the effective anti-viral dose) every day for four weeks to healthy volunteers to investigate the safety of excessive intake of LC-Plasma. Trial Design: A randomized, double-blind, placebo-controlled, parallel-group trial was conducted. Methods: Forty healthy subjects were randomly assigned to the LC-Plasma group (daily intake of five capsules containing 50 mg heat-killed LC-Plasma cells per capsule) or the placebo group (daily intake of five placebo capsules with no LC-Plasma). Physical, hematological, biochemical and urinary examinations and medical interviews were used to evaluate safety. Results: No abnormal differences were observed after excessive intake of LC-Plasma capsules when compared to the intake of placebo capsules. Conclusions: There are no safety concerns associated with the excessive intake of heat-killed LC-Plasma capsules.

Lactic Acid Bacteria, Lactococcus lactis, Excessive Intake, Safety

Kato, Y. , Kanayama, M. , Yanai, S. , Nozawa, H. , Kanauchi, O. and Suzuki, S. (2018) Safety Evaluation of Excessive Intake of Lactococcus lactis Subsp. lactis JCM 5805: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial. Food and Nutrition Sciences, 9, 403-419. doi: 10.4236/fns.2018.94032.