Beetroot juice may reduce blood pressure

Posted by AFN Staff Writers on 27th May 2013

A cup of beetroot juice a day may help reduce blood pressure, according to a study published in April 2013 in the American Heart Association journal Hypertension.

The study, which was funded by the British Heart Foundation, found that people with high blood pressure who drank about 8 ounces of beetroot juice experience a decrease in blood pressure of about 10 millimeteres of mercury (mm Hg).

The beetroot juice contained about 0.2g of dietary nitrate – levels that might be found in a large bowl of lettuce or two whole beetroots. In the body, nitrate is converted into a chemical called nitrite and then to nitric oxide in the blood. Nitric oxide is a gas that widens blood vessels and aids blood flow.

“We were surprised by how little nitrate was needed to see such a large effect,” said Amrita Ahluwalia, lead author of the study and a professor of vascular pharmacology at The Barts and The London Medical School in London.

“This study shows that compared to individuals with healthy blood pressure much less nitrate is needed to produce the kinds of decreases in blood pressure that might provide clinical benefits in people who need to lower their blood pressure. However, we are still uncertain as to whether this effect is maintained in the long term,” Professor Ahluwalia said.

Study method

The study involved eight women and seven men who had a systolic blood pressure between 140 to 159 mm Hg, did not have other medical complications and were not taking blood pressure medication. The study participants drank 250 mL of beetroot juice or water containing a low amount of nitrate, and had their blood pressure monitored over the next 24 hours.

Blood pressure is typically recorded as two numbers. Systolic blood pressure, which is the top number and the highest, measures the pressure in the arteries with the heart beats. Diastolic blood pressure, the bottom and lower number, measures blood pressure in the arteries between heart beats.

Compared with the placebo group, participants drinking beetroot juice had reduced systolic and diastolic blood pressure – even after nitrate circulating in the blood had returned to levels present prior to drinking beetroot juice. The effect was most pronounced three to six hours after drinking the juice, but still present even 24 hours later.

“Our hope is that increasing one’s intake of vegetables with a high dietary nitrate content, such as green leafy vegetables or beetroot, might be a lifestyle approach that one could easily employ to improve cardiovascular health,” Professor Ahluwalia said.

High blood pressure in Australia

According to the Australian National Heart Foundation, high blood pressure (or hypertension) is the most common of all the conditions of the circulatory system.

According to the National Heart Foundation, in 2011-12, 3.1 million Australians, or 21.5 per cent, aged 18 years and over had high blood pressure. High blood pressure is when systolic or diastolic blood pressure is equal to or greater than 140/90 mm Hg.

The National Heart Foundation said that in 2011-12, the prevalence of high blood pressure was lowest in the Northern Territory (15.9 per cent) and Queensland (18.9 per cent). Prevalence of high blood pressure was highest in Tasmania (30.4 per cent).

Prevalence of high blood pressure in New South Wales in 2011-12 was 21.3 per cent, in Victoria 23 per cent, in South Australia 23.4 per cent, in Western Australia 21 per cent, and in the Australian Capital Territory 20.1 per cent.