Five type II diabetic patients (2 males and 3 females, 61-74 years of age) were immersed in cold-spring water (13°C) for 15min, twice or 3 times a day for consecutive 12 days at Kan-no-Jigoku spa in Japan.
In all of the patients, both systolic and diastolic blood pressures rose, and pulse rate increased during the acute cold exposure. This circulatory response to cold-water immersion tended to decrease after 12 days' serial immersions. After each immersion, blood glucose levels are lowered in all of the patients, suggesting the enhanced uptake of glucose by the tissue. After the 12 days' cure, 2 patients with relatively lower severity of diabetes showed improved glucose tolerance estimated by 50g oral glucose tolerance tests. No significant improvement of insulin secretion was observed in 25g intravenous glucose tolerance tests in the present study. Among 3 patients whose urinary output of glucose was measured daily, 2 patients showed gradually decreased urinary glucose and one showed almost no glucosuria throughout the 12 days' cure.
These results indicate that cold-water immersion stimulates the utilization of glucose as seen in exercise and that repeated cold-water immersions, if performed carefully, could be a regimen for diabetic patients.