This study was conducted to evaluate the efficacy and safety of heat-treated Lactiplantibacillus plantarum LM1004 in improving immune function in adults.

This was a randomized, double-blind, placebo-controlled, single-center clinical trial. Healthy adults aged 19 to 75 years who met the eligibility criteria were enrolled and randomly assigned to receive either the study product or a placebo. Participants in the study group received heat-treated Lactiplantibacillus plantarum LM1004, while participants in the control group received a placebo.

The study product or placebo was taken once daily for 8 weeks. The primary outcome of the study was the change in natural killer (NK) cell activity from baseline. Secondary outcomes included changes in immune-related biomarkers, such as cytokines, white blood cell counts, total IgE levels, and fatigue-related questionnaire scores. Safety was evaluated by monitoring adverse events, vital signs, and laboratory test results throughout the study period.

The results of this study were intended to determine whether daily intake of heat-treated Lactiplantibacillus plantarum LM1004 is safe and may help improve immune function in adults.

Inclusion Criteria:

• Healthy male or female adults aged 19 to 75 years
• Able to understand the study procedures and provide written informed consent
• Willing to comply with the study protocol

Exclusion Criteria:

• History of chronic or serious medical conditions that could interfere with study participation
• Use of medications or supplements that may affect immune function within the screening period
• Pregnant or breastfeeding women
• Participation in another clinical study within 3 months prior to screening