PREGNANT women can reduce their blood pressure by consuming beetroot juice, a study from the University of Manchester, Manchester, UK has suggested. A research team discovered that supplementation of nitrate-rich beetroot led to increases in blood nitrite levels that were strongly associated with reduced diastolic blood pressure in a cohort of hypertensive pregnant women.
“Women with increased blood pressure are at increased risk of developing pre-eclampsia, and all the associated dangers of this such as poor growth of the baby in the womb, preterm delivery, and maternal seizures,” commented study author Dr Jenny Myers, University of Manchester. “So, if there are indeed benefits of having nitrate in their diet, it might have implications on the development of treatments for pregnant women with high blood pressure.”
The differences in plasma nitrite and diastolic blood pressure were observed 2–3 hours after consumption of a daily 70 mL beetroot juice shot. This daily shot was taken by 20 pregnant women with moderately high blood pressure over a period of 8 days. In a second group of hypertensive pregnant women, who were instead given a placebo beetroot juice which had the nitrate removed, there were no changes to their blood nitrite or nitrate levels. No overall reduction in blood pressure was shown in either the nitrite or placebo groups.
Role of Oral Bacteria
The team believe that the differences in blood nitrite levels between the two groups could be linked to the activities of bacteria in the mouth; previous studies have shown the substantial role these bacteria have in turning nitrate into nitrite. “Understanding this biology better could have important implications in our hunt for sustainable ways to intervene in the cycle which regulates blood pressure,” said lead author Dr Lizzy Cottrell, University of Manchester. “Our next step will be to investigate the role of the bacteria that live in the mouth in determining blood pressure regulation in pregnancy, and how that links to the ability of nitrate supplementation to lower blood pressure.”
The study built on earlier work displaying that blood pressure in non-pregnant adults can be reduced through supplementation with dietary nitrate. The team emphasised, however, that it is too early for beetroot juice to be considered as an effective method of controlling blood pressure in pregnant women.
James Coker, Reporter