A recent clinical study, supported by Malaysian pharmaceutical and nutraceutical company Pharm-D Health Science Sdn. Bhd, investigated the effects of a daily probiotic on 152 participants over a span of six months.
The findings suggest that L. plantarum K014 is safe for long-term consumption in healthy individuals; however, the researchers emphasized the need for further studies with a larger sample size to determine any significant health advantages associated with this strain, as noted in the journal Nutrients.
Strain-Specific Effects
L. plantarum has been recognized as generally safe for human consumption and is commonly found in dietary supplements and fermented foods. The probiotic strain has demonstrated beneficial effects on gut health and the immune system, showing potential advantages for weight loss, loose stools, cognitive function, and sleep.
Nevertheless, the current study also highlights that L. plantarum has been linked to adverse effects in some clinical trials, such as exacerbating IBS symptoms and not improving intestinal permeability. These findings illustrate the importance of understanding that probiotic effects can vary by strain and necessitate specific evaluations of safety and tolerance.
The L. plantarum K014 strain, isolated from local Malaysian cabbage by researchers at Universiti Sains Malaysia, is patented and marketed as Lassica KO14.
The primary objective of the study was to evaluate the safety profile of this previously uncharacterized strain in an early-phase clinical trial.
“The absence of any adverse effects, combined with trends indicating reduced gastrointestinal discomfort and immune-related symptoms, supports the consideration of L. plantarum K014 for further efficacy studies,” the research team reported.
Study Details
In the randomized study, 152 healthy adults were assigned to receive either L. plantarum K014 (≥1 × 109 CFU/day) or a placebo on a daily basis for six months. Participants underwent clinical assessments at the beginning, at the fourth month, and at the end of the six months, including measures of body composition and blood samples for safety assessments, glucose levels, cholesterol profiles, and immune markers. Weekly online questionnaires were used to track gastrointestinal symptoms, stool characteristics, and immune-related outcomes.
Analysis of blood test results showed that levels of red and white blood cells remained normal and stable across both groups. There were no negative impacts on glucose or lipid metabolism, with values consistent throughout the trial. Evaluations of liver and kidney function indicated no adverse effects, along with a possible positive influence on protein metabolism and immune-related globulin synthesis.
No significant differences were observed between the groups regarding gastrointestinal symptoms; however, exploratory analyses revealed lower instances of diarrhea and abdominal pain among those taking the probiotic.
Common cold symptoms and daily functioning were comparable in both groups. An exploratory analysis also indicated a modest yet significant improvement in the number of workdays affected in the group taking the probiotic.
The researchers acknowledged certain limitations of the study, including a homogenous sample and reliance on self-reported outcomes. They called for future research to thoroughly explore safety across a more diverse population.
Source: Nutrients 2026, 18(9), 1406; doi: https://doi.org/10.3390/nu18091406; “Safety of Lactiplantibacillus plantarum K014 in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial.” Authors: K.S. Goh et al.
