High blood pressure: 3 cups of coffee a day can lower blood pressure

A new study has found that drinking three or more cups of coffee is associated with lower blood pressure.

People are generally advised not to drink too much coffee because caffeine can increase blood pressure.

However, coffee also contains some compounds that may lower blood pressure.

This study provides evidence that moderate coffee consumption may be safe for people with high blood pressure.

A new study published in the journal Nutrients reports that drinking three or more cups of coffee daily was associated with lower peripheral and central blood pressure.

The lead author of the study, Dr. Arrigo F.G. Cicero, associate professor in the Department of Medical and Surgical Sciences at the University of Bologna, peripheral and central blood pressure are markers of arterial stiffness and aging.

In older adults with high blood pressure, the large arteries become stiffer, leading to higher systolic blood pressure (the top number of a blood pressure reading) and wide pulse pressure (the difference between the top and bottom numbers).

The authors note in their report that the effects of coffee on blood pressure are still debated, primarily because it is known that coffee's caffeine content can raise blood pressure in the short term.

However, these effects may be mitigated by antioxidants found in coffee that may help dilate blood vessels and protect cells from free radicals.

Regular coffee drinking linked to lower blood pressure

Cicero and his team wanted to investigate how the interaction between caffeine and other compounds found in coffee would affect the incidence of blood pressure.

To conduct their study, Cicero's team examined a sample including 720 men and 783 women participating in the Brisighella Heart Study.

This ongoing study, which first began in 1972, includes a random sample representative of a rural northern Italy town called Brisighella.

The researchers looked at participants' blood pressure and coffee-drinking habits, as well as a selection of other data related to heart health.

Upon analysis of the data, they found that coffee consumption was associated with lower blood pressure.

"The trend from 2 [cups] of coffee per day appears to be positive," Cicero said. "So, coffee drinking should not be prohibited in current coffee drinkers if there is a fear that coffee may increase BP levels."

Why coffee may help with blood pressure

Megan K. Rhodes, PhD and postdoctoral scholar, Department of Medicine, Department of Nephrology at the University of Alabama at Birmingham, said there are a few mechanisms through which coffee consumption may lower blood pressure, some of which have been demonstrated in animal studies.

"Coffee contains caffeine, which can raise and lower blood pressure in acute settings, but it also contains antioxidants and bioactive compounds that may be responsible for the blood pressure-lowering effect," she explained.

Rhoads cited chlorogenic acid as an example of a compound that could lower systolic blood pressure in rats.

"When processed by the gut microbiota, chlorogenic acid is broken down into metabolites that may increase nitric oxide bioavailability and lower blood pressure."

Dr. Debabrata Mukherjee, chair of the department of internal medicine and professor of internal medicine at Texas Tech University Health Sciences Center El Paso, further explained: "Even though caffeine can increase BP levels (especially in individuals who do not normally drink coffee) drink), the amount of other bioactive compounds in coffee balances this effect with an eventual neutral-to-positive effect on BP.

According to Mukherjee, chlorogenic acid, which is present in the highest concentration in coffee beans, is believed to be one of the main compounds in coffee that lowers blood pressure. Quercetin may also play a role.

Should people with high blood pressure drink coffee?

Dr. Jim Liu, a cardiologist at The Ohio State University Wexner Medical Center, said that although the study is small and focused on a specific population, its findings are consistent with prior knowledge of how coffee affects blood pressure.

He added, "Coffee can acutely raise blood pressure after consumption, but there is really no solid evidence to show that moderate amounts of coffee cause long-term problems with high blood pressure or heart disease in general." "

What does this mean for people with high blood pressure?

"For patients with high blood pressure who consume moderate amounts of coffee, this study provides some more reassuring data that it is okay to continue drinking coffee in moderate amounts and will not negatively affect blood pressure. However, moderate coffee consumption may help with blood pressure," Liu said.

Mukherjee said that moderate consumption would be the equivalent of about four or five cups of coffee, although it is "not recommended for people with existing severe hypertension."

The American Heart Association notes that people are advised to avoid drinking "too much" coffee because of its potential to raise blood pressure. It can also cause insomnia, heart palpitations and anxiety.