Fiber comes only from plant-based foods, as animal products have no fiber. Eating a diet high in fiber may help reduce high blood pressure in hypertensive patients, according to a study that appeared in the Journal of Hypertension in 2005. By analyzing the results of 25 randomized controlled trials, researchers from Tulane University School of Public Health in New Orleans, USA, found an inverse association between high intake of dietary fiber and elevated blood pressure. For maximum reduction in blood pressure, the authors recommend that individual should regularly eat generous amounts of fiber-rich foods for a minimum duration of 8 weeks.

The results of this study are in line with the findings of a similar study conducted by a group of researchers from the Imperial College, London, and Northwestern University in the United States. The researchers examined the fiber consumption levels of over 2,000 American men and women within the age bracket of 40 – 59 years and regularly assessed the blood pressure values of all the participants in this study. The investigators discovered that a 1.69 mmHg and 1.81 mmHg drop in systolic pressure were associated with subjects whose fiber consumption rates were 4.6 grams per 1,000 kilocalories for insoluble fiber and 6.8 grams per 1,000 kilocalories for total fiber respectively. "Higher intakes of fiber, especially insoluble, may contribute to lower blood pressure, independent of nutrients associated with higher intakes of fiber-rich foods" the authors concluded.

The researchers proposed a number of mechanisms used by dietary fiber to lower high blood pressure. Some of them include boosting nitric oxide secretion, enhancing insulin sensitivity, reducing sodium absorption via improved endothelial function, and increasing favorable biomarkers of cardiovascular disease. These different actions of dietary fiber help it to transform a high blood pressure number to a healthy one.  Vegans who eat a high-fiber diet of low-fat whole unprocessed plants have been shown to have a lower incidence of hypertension, especially if the diet is also oil-free.

About 75 million Americans have high blood pressure. To put this figure into proper perspective, 1 in 3 Americans are battling with high blood pressure, but that figure rises to more than 66% of those older than age 65. Unfortunately, this health condition can lead to other diseases, such as stroke, heart attack, dementia, retinopathy, headaches and chronic kidney disease. Eating animal products can raise our risk for high blood pressure. Plates filled with high-fiber vegetarian foods, such as fruits, vegetables, and whole grains, can boost our chances of preventing this silent killer.

Additional Information:

(1) High Blood Pressure Fact Sheet

(2) Effect of Dietary Fiber Intake on Blood Pressure: a Meta-Analysis of Randomized Controlled Clinical Trial

(3) High-Fiber Diet May Fight High Blood Pressure