Diuretics are drugs designed to cause the kidneys get rid of some of the excess salt in the body as there is a strong relationship between high blood pressure and a high content of salt in our system. As a result, diuretics tend to lower blood pressure, although they don't always do a good job in this area.
Now a new and controversial book by an American doctor suggests that taking even higher levels of the vitamin - 10 to 15 times the recommended amounts - can work wonders.
Dr James Dowd, who works at the Arthritis Institute of Michigan, has been prescribing vitamin D to people suffering from chronic disorders such as arthritis, back pain and headaches and the result, he claims, is a huge improvement in their symptoms.
In his book, The Vitamin D Cure, Dr Dowd describes a number of success stories using this approach. One of his patients, Barbara, for instance, was obese, and suffered from arthritis in one leg as well as high blood pressure.
As Dowd explains: "In the past I would have given her anti-inflammatory drugs, pain medication, a pill to lose weight and drug treatment for hypertension."
What is chlorella if not an inexpensive and easy to grow food source? Now it's promoted for its claimed health advantages, that contain lowering high blood pressure.