Blueberries Beat Drugs for Hypertension
I used to jokingly tell friends that after researching health topics for years, I concluded that the only foods that won’t kill you are organic blueberries and broccoli. Then I found out that broccoli, like all cruciferous vegetables, may be laden with the heavy metal thallium, a rat poison component that has harmful nervous system effects and causes birth defects.1 (In truth, although cruciferous vegetables “can” accumulate heavy metals, there is no peer-reviewed research that indicates they are actually making people sick.) That news, taken with a grain of salt, made blueberries my sole remaining food that doesn’t kill; and while that’s a wild exaggeration, of course, new research adds evidence to support the supremacy of the blueberry.
We’ve written before about how blueberries reverse dementia, shrink tumors, fight PTSD, and lower blood pressure. As we described, a 2015 study found that women who consumed 22 grams of blueberry powder daily reduced their systolic blood pressure by an average of 5.1 percent and diastolic blood pressure by 6.3 percent. That level of reduction, while significant, wouldn’t be enough to restore a severely or even moderately hypertensive individual to the normal range. But new research delivers better news: according to a study out of King’s College in London, blueberries can lower blood pressure as effectively as medication and can reduce heart disease risk by 20 percent.
The study involved 40 individuals who consumed the equivalent of 200 grams of blueberries daily via a blueberry drink.2 That’s a whole lot of blueberries—about a cup and a half to two cups a day.3 After a month of this regimen, participants lowered their blood pressure by an average of 5 mmHg, which is about the same reduction the typical patient experiences using blood-pressure medication. Even more, the researchers found that the blueberry drink improved blood vessel function. Within just two hours of consuming the blueberries, the subjects had improved “flow-mediated dilation” (FMD) of the brachial artery—the artery that supplies blood to the arm and hand and that’s typically used to measure your blood pressure. The FMD measurement indicates how much the brachial artery opens.
Improved FMD means the arteries widen more easily as blood flow increases. Flexible arteries are essential to cardiovascular health—conversely, stiff, narrow arteries are a major contributor to high blood pressure and cardiovascular disease. In healthy individuals, as the heart pumps blood to the muscles, the arteries widen easily to allow the flow, but when the arteries are narrow or unresponsive, as may happen with aging, the muscles in the artery walls have to work harder to transport the blood, and that raises blood pressure as well as the risk that the artery could burst and cause a stroke or heart attack. Again, consuming blueberries contravenes that risk fast, and within two hours of consumption.4 Plus, blueberries improve endothelial function. Endothelial cells are essential to blood pressure regulation and blood clotting.
The blueberry effect was so significant that chief researcher Dr. Ana Rodriguez-Mateos concluded, “If the changes we saw in blood vessel function after eating blueberries every day could be sustained for a person's whole life, it could reduce their risk of developing cardiovascular disease by up to 20%."
What is it that makes blueberries such a wonder food? It turns out that the magic component is the “blue factor.” Although blueberries are loaded with vitamins, minerals, and healthy fiber, it’s a phytochemical called anthocyanin that confers the cardiovascular benefits. Anthocyanins are present in other berries as well, and also in grapes, blue corn and assorted other fruits and vegetables, coloring them blue, red, pink, or purple.5 When the subjects drank a beverage containing purified anthocyanins instead of whole blueberries, the benefits to endothelial function showed up, which led the researchers to speculate that the anthocyanins were responsible for the cardiovascular benefits. Still, Dr. Rodriguez-Mateos advises eating, “the whole blueberry to get the full benefit” rather than just taking an anthocyanin isolate.
Given that hypertension medications come with side effects ranging from the miserable to the dangerous, eating a few cups of delicious berries seems a good deal indeed. Even more, in recent months, several common blood pressure medications have been recalled because they were contaminated with carcinogens. Most recently, the angiotensin receptor blocker (ARB) drug Losartin was recalled after the Food and Drug Administration found it to be contaminated by several known cancer-causing agents. Other ARB drugs were recalled previously. What’s particularly disturbing is that according to the commissioner of the FDA, Dr. Scott Gottlieb, the carcinogenic impurities may be the result of “specific chemical reactions in the manufacturing process of the drug's active pharmaceutical ingredients.”6 The statement underlines the fact that pharmaceuticals may, by their very nature, be harmful and alien to human physiology.
Again, the list of possible side effects from blood pressure medications, even minus the contamination, is long and worrisome. In contrast, the only side effects from blueberries might be stained hands and tongue and the happy feeling of having eaten something yummy. One word of warning, though: if you have diabetes, you do need to monitor your fruit intake. Blueberries contain about 15 g of sugar per cup. You don’t want to lower your blood pressure at the cost of sending your blood sugar into the ozone.
- 1. Oppenheimer, Todd. “The Vegetable Detective.” Craftsmanship Quarterly. 2 March 2019. https://craftsmanship.net/the-vegetable-detective/
- 2. Ana Rodriguez-Mateos, Geoffrey Istas, Lisa Boschek, et al. "Circulating anthocyanin metabolites mediate vascular benefits of blueberries: insights from randomized controlled trials, metabolomics, and nutrigenomics." The Journals of Gerontology: Series A, glz047. 16 Feb 2019. https://academic.oup.com/biomedgerontology/advance-article-abstract/doi/10.1093/gerona/glz047/5321875?redirectedFrom=fulltext
- 3. St. John, Dr. Tina. “What is a Serving Size of Blueberries?” Livestrong. 1 March 2019. https://www.livestrong.com/article/387016-what-is-a-serving-size-of-blueberries/
- 4. Kings College London. “The blue in blueberries can help lower blood pressure.” 20 February 2019. Medical Xpress. 3 March 2019. https://medicalxpress.com/news/2019-02-blue-blueberries-blood-pressure.html
- 5. https://naturalon.com/top-25-anthocyanin-rich-superfoods-and-why-you-should-eat-them/view-all/
- 6. “Blood pressure medication recall expands again for possible cancer risk.” 4 March 2019. Houston Chronicle. 4 March 2019. https://www.chron.com/news/article/Blood-pressure-medication-recall-expands-again-13661319.php