Fasting primarily affects blood pressure by:

Fasting primarily affects blood pressure by decreasing it. This is due to several physiological changes that occur during periods of fasting. When a person fasts, the body begins to utilize stored energy, including glycogen and fat. This metabolic shift can lead to a reduction in overall energy expenditure, which may result in lower heart rates, reduced sympathetic nervous system activity, and improved vascular function. These changes can contribute to lower blood pressure.

Additionally, fasting can promote beneficial hormonal changes, such as increased levels of catecholamines, which can impact vascular resistance. Furthermore, a reduction in body weight during prolonged fasting can also lead to decreased blood pressure levels. Collectively, these factors explain why fasting is often associated with a decrease in blood pressure, especially in individuals with hypertension.