The term QOL (Quality of Life) is used to evaluate the level of mental and physical satisfaction with daily life (the purpose of life). QOL can be assessed objectively using QOL questionnaires those results can be quantified and analized statistically.
Health-Related QOL is focused on one’s physical condition, and the questionnaire is narrowed down almost exclusively to health-related items. Since HK L-137 has immunostimulating activity and immune functions are related to the physical conditions, the changes in physical conditions in healthy subjects taken HK L-137 were evaluated using QOL questionnaires in this study.
The results have revealed that HK L-137 improves the QOL, indicating that its immunostimulating activity can exert health promotion effects.
A double-blind randomized controlled trial was conducted in 60 healthy male and female volunteers aged 40 years or older. Thirty subjects received a capsule containing 10 mg of HK L-137 once daily for 12 weeks, and another set of 30 subjects received a capsule containing no HK L-137 once daily for 12 weeks. The efficacy of HK L-137 was evaluated by examining the immune functions and health-related QOL of the subjects at Weeks 0, 4, 8, and 12 after the beginning of the trial.
Health-related QOL was assessed using a questionnaire with 26 items regarding physical and mental functions. The answer to each item was chosen from three options and then scored. Total QOL score was calculated by summing all the scores of the items. The degree of QOL improvement was defined as 100% if the total QOL score increased from the beginning of the study, 0% if unchanged, and ?100% if decreased. Mean value of the degree of QOL improvement in each group was calculated and compared.
In the HK L-137 group, a significant increase in the degree of QOL improvement was observed at Week 8 after the beginning of the study (P=0.049), and the increased level was maintained until Week 12 after the beginning of the study (P=0.092).
In the HK L-137 group, an enhancement of immune functions (increase in the proliferation of T cells and increase in the Th1/Th2 ratio) was observed from Week 4 after the intake, and the increased level was maintained until the end of the study. Such effects of HK L-137 on immunity may be responsible for the improvement of QOL, which was observed following to the increases in immune functions.
The study demonstrated that HK L-137 not only increases the immune functions, but also improves the physical condition, suggesting that HK L-137 is a very useful food ingredient to maintain and improve our health.
Reference:J Nutr 136: 3069-3073, 2006