Abstract
Bitter melon is specialty food produced in Okinawa prefecture in Japan, where people enjoy notable longevity. The effect of bitter melon malt vinegar on energy metabolism was determined, and compared between normal LETO rats and genetically diabetic OLETF rats. Administration of a diet containing bitter melon malt vinegar increased daily food intake and daily energy expenditure in both strains. In LETO rats, the respiratory quotient (RQ) was decreased and the fat-derived energy used for combustion was increased by bitter melon malt vinegar. In diabetic OLETF rats, the profile of daily energy expenditure was normalized; two peaks in the daily profile of energy expenditure, which were disappeared in OLETF rats on the control diet at 24 weeks of age, were reproduced by administration of bitter melon malt vinegar. As a consequence of blood or plasma inspection, it turned out that there was no change in HbA1c but a significant increase in plasma cholesterol in the vinegar diet-fed OLETF rats. From these results, a long-term administration of bitter melon-malt vinegar can be expected to suppress a lowering of energy turnover inherent with aging and thereby improve anorexia rather than to bring about a preventive effect against the manifestation of NIDDM. [Jpn J Physiol 54 Suppl:S236 (2004)]
