Dr. Pradip Jamnadas:

Insulin and Blood Pressure: Dr. Jamnadas states that “high insulin levels act as a vasoconstrictor, meaning they narrow blood vessels. He explains that insulin reduces nitric oxide in the blood vessels, and nitric oxide is a natural vasodilator that helps blood vessels dilate. Essential Hypertension is often caused by high levels of insulin, this being the root cause of High Blood Pressure.”

“Fasting can lead to relief from high blood pressure by primarily addressing high insulin levels.”

This video is where Dr Jamnadas explains this point.