Hypertension is becoming pandemic and WHO estimated the prevalence rate of hypertension being one-third of people aged above 25 years old. Number of patients with hypertension in Japan increased from 9,067,000 in 2012 to 10,108,000 in 2015, and its medical cost was 1,889 billion yen. Number of annual death was 6,932, so the prevention of hypertension is an urgent issue, because of its high risk for cardiovascular disease, cerebral palsy, renal insufficiency, and so forth.We found that suitable fasting is effective in maintaining and/or promoting health, and hypoglycemia by fasting yielded a high concentration of acetone body, especially β-hydoxybutyrate. We also found systolic and diastolic blood pressure decreased during fasting and its effects continued at least one month later. It seemed to be a legacy effect of the wellness fasting, so we analyzed the factors and considered the mechanism of this phenomenon.