Studies on human adaptability to climatic conditions. 3. Seasonal variations in serum FFA on Japanese and Americans in Japan

Abstract

In addition to the previous two reports submitted regarding the BMR and PBI in serum on the Japanese and American nationals, this experiment was conducted on the free fatty acids in serum of the same subjects with those in the first report, for about one year commencing in June 1969.Results are as follows:1) As for serum FFA, results were higher in Americans than in Japanese.2) As for relationship between serum FFA and the RQ in basal metabolism a significant inverse correlationship was noted in subjects with a higher serum FFA showed a higher fat combustion rate, however, this relationship was significant only for Japanese.3) Relationship between the serum FFA and BMR showed a seasonally slight different trend. While FFA and BMR correlated positively in summer, the relation inclined to be reverse during the period of cold adaptation.4) As for relationship between serum FFA and external temperature, FFA showed a high value during the season in which the temperature was higher. It was noted that there was a tendency for the FFA level to lower during low temperature season. This trend was clearly noted on Japanese nationals, however, almost no such tendency was observed in American nationals.5) A significant correlationship of FFA and PBI was not noted in this experiment.