To Lower High Blood Pressure, Switch to a Plant-Based Diet, New Study Shows

If you're one of the 108 million Americans with high blood pressure, you may wonder: What does it mean, how does it happen, and how can I get rid of it? Now there is a new study that shows one way to lower blood pressure to a healthy level is to switch to a plant-based diet.

Here's what you need to know: High blood pressure is caused when the force of blood passing through the arteries is too high, and over time, it leads to elevated blood pressure that if left untreated can cause serious health problems like heart disease and stroke. Blood pressure goes up when the arteries narrow or gets blocked by calcium deposits or plaque, often caused by eating too much saturated fat in the diet. But blood pressure can also become elevated by chronic stress which causes inflammation, studies show. In medical terms, this condition is called hypertension and it can affect nearly anyone — even children. in fact, almost half of all adults in the US have hypertension, according to the CDC.

Another form of high blood pressure that is specific to the last half of pregnancy is preeclampsia, which occurs in 8 percent of all pregnancies, according to the Mayo Clinic. Preeclampsia shows up in women after 20 weeks of pregnancy and can onset suddenly, even if you’ve had normal blood pressure through the early weeks of pregnancy and before.

Now a new report that includes reviews of two separate studies on animals has found that a plant-based diet is protective against both hypertension and preeclampsia.

Every time our heart beats, it pumps blood to all areas of our body, and back. Our blood pressure is determined by the amount of friction the blood meets along the 60,000 miles of blood vessels–arteries, veins, and capillaries–and how hard the heart has to work to move it through the system. When we have narrow arteries, our blood pressure rises.

When you get your blood pressure tested by a medical professional, you're given two numbers, as in 115/70. The top one is our systolic pressure, which is the pressure in your arteries as your heart beats, and the bottom number, or diastolic pressure, is the pressure in your arteries between beats. Both of these are given in millimeters of mercury (mm Hg). Normal blood pressure should have a systolic pressure of less than 120 mm Hg and a diastolic reading of less than 80 mm Hg, according to the CDC.

Although there are many factors that can increase the risk of both hypertension and preeclampsia, a common factor is diet, especially one that is high in salt (or sodium) since it causes your body to retain fluid and increase blood pressure.

A report conducted by researchers at the Medical College of Georgia and Medical College of Wisconsin. The two studies found that our gut microbiota —which is the bacteria in the intestines responsible for digestive health and that controls everything from arterial hardening to immune system support— plays a role in how our body responds to salt. “The findings provide more evidence of the ‘potential power’ of nutritional intervention to improve the gut microbiota, and consequently our long-term health.” wrote Dr. David L. Mattson, chair of the MCG Department of Physiology, Georgia Research Alliance Eminent Scholar in Hypertension and senior author of the two studies,

To find out if a specific diet made a difference in reversing and lowering high blood pressure, researchers bred lab rats to develop hypertension and progressive kidney disease on a high-salt diet and called them “Dahl salt-sensitive rats.” Some of the rats were fed a milk-based protein diet while others were switched to a grain-heavy plant-based diet. Both of these diets were relatively low in salt.

When high-salt content was added back into the rats' diets, the rats who were given the plant-based diet developed significantly less high blood pressure and kidney damage than the rats on the milk-protein diet. “The animal protein amplified the effects of the salt,” commented Mattson in an interview.

“Since the gut microbiota has been implicated in chronic diseases like hypertension, we hypothesized that dietary alterations shift the microbiota to mediate the development of salt-sensitive hypertension and renal disease," the authors Mattson, along with physiologist, Dr. Justine M. Abais-Battad, and postdoc, Dr. John Henry Dasinger, wrote, in the journal ACTA PHYSIOLOGICA and Pregnancy Hypertension: An International Journal of Women's Cardiovascular Health. They looked at the microbiomes in the rats. “Sure enough, they were different,” commented Dr. Abais-Battad.

When researchers transferred the gut microbiota from the animal-protein-fed rats to the plant-based rats, they saw a rise in blood pressure, kidney damage, and the number of immune cells moving into the kidneys. When they shared the microbiota from the protected plant-based rats to the animal-based, they didn’t see a beneficial impact. The reason? Scientists say the beneficial microorganisms couldn’t flourish when the rats were being fed an animal-based protein diet.

Preeclampsia can be a lethal problem during pregnancy, which led to further research on how a plant-based diet could affect these Dahl-sensitive rats during their pregnancies.

Each group of rats was kept on their animal-protein diet or plant-based diet, which each remained low in salt, and had three separate pregnancies and deliveries. Rats who were given the plant-based diet were protected against preeclampsia while around half of the rats on the animal-based diet developed this condition.

There was a “significant increase in the protein spilled into their urine; an indicator of kidney trouble," Dasinger wrote, "Which worsened with each pregnancy; increased inflammation, a driver of high blood pressure; increased pressure inside the renal artery; and showed significant signs of kidney destruction when the organs were studied on follow up.” The animal-protein group of rats wound up dying of problems associated with preeclampsia including stroke, kidney disease, and other cardiovascular problems.

“This means that if mom is careful with what she eats during pregnancy, it will help during the pregnancy, but also with her long-term health and could provide protective effects for her children,” commented Dasinger in an interview.

Dasinger plans to conduct further research on how diet could impact offspring and if breastfeeding while on a plant-based diet could pass on a protective effect.

Bottom Line: To lower blood pressure, switch to a plant-based diet and avoid salt.