A widely reported study from India shows that eating just two medium sized bananas a day for a week can lower blood pressures by 10%.1
Hypertension has many causes. The most common of which are associated with our high sodium “Western” diet and sedentary lifestyles. Those of us with high blood pressure are exhorted to adopt a healthy balanced diet to help manage our condition. However, little or no explanation of this entreaty is given. Instead, medication that undermines some aspects of a healthy diet may be prescribed.
Diet and high blood pressure:
Our bodies are complex organisms that require a certain balance of nutrients for optimum performance. Hypertension can result from an imbalance of nutrients. Our modern “Western” diet is often low in fresh fruits, nuts and vegetables. These are the main sources of the nutrients we need to maintain our blood pressures at healthy levels. Our diet often has an over-supply of sodium and, more often than not, there is a deficiency of potassium. That deficiency is a common cause of hypertension.
The recommended daily amount of potassium for an adult is 4,700mg. Most people’s diet gives them less than half of this amount. Bananas are a good source of potassium, with a medium size banana providing about 10% of our daily requirement for that mineral. Bananas are especially beneficial because they contain almost no sodium.
Potassium and hypertension:
A banana a day can help keep strokes at bay
– Daily Express 4 September 2014
Potassium plays a role in regulating blood pressure. A 1997 study carried out at John Hopkins University in the USA 1, and which focussed on the role of potassium, suggested people would have to eat five bananas a day to have half the effect of a blood pressure-controlling medication. With the knowledge we now have, the finding is not unexpected given that:
- there is an inverse relationship between our blood pressure and the amount of potassium we consume; and
- five bananas only provides half of the RDA for potassium for an adult.
Research conducted by scientists at Kasturba Medical College in Manipal in southern India, after the John Hopkins University study, found that blood pressure fell by 10% in people who ate two bananas daily for a week2. This is as effective as anti-hypertensive medication, but without the side effects.
How does eating 2 bananas a day lower high blood pressure?
This is achieved in two ways:
Firstly, bananas are a rich source of potassium and have almost no sodium. Potassium reduces the effect of sodium on the body 3, which is to increase the strain of the flowing blood on the arteries. Eating two bananas a day boosts our potassium intake and reduces the effect of sodium, which helps regulate our blood pressures.
Secondly, bananas contain a natural angiotensin converting enzyme (ACE) inhibitors. ACE produces a substance called angiotensin-2 that constricts blood vessels and raises the pressure inside them. Eating bananas has been shown to stop this happening.
Bananas have many health benefits. Including two bananas a day in our diet is a healthy way to lower our high blood pressure naturally4.