This Drink May Help Lower Blood Pressure

High blood pressure, or hypertension, is common in the U.S. In fact, there’s a good chance you have it, since half of all American adults are living with the condition. And about one in three adults with high blood pressure aren’t even aware they have it. This is because it usually comes with no symptoms. This doesn’t mean, however, that it’s benign.

Blood pressure is the amount of force your blood exerts on the walls of your arteries, the blood vessels that carry oxygenated blood from your heart to the rest of the body. If left untreated, high blood pressure can damage organs, including the heart, eyes, kidneys and brain, increasing your risk of heart disease, stroke and chronic kidney disease.

Besides factors out of your control, like genetics, age, sex and ethnicity, lifestyle also plays a large role in blood pressure. This includes diet, physical activity, stress and sleep. Researchers have observed that following an eating pattern like the DASH diet can help manage blood pressure. But what about specific foods that you can start adding to your diet?

Researchers in Iran and at the University of Nevada did a systematic review and meta-analysis to see what studies show regarding green tea and blood pressure. They published their findings in the journal Blood Pressure. Let’s break down what they found.

How Was This Study Conducted?

Researchers searched databases for previously conducted studies that met their criteria. Specifically, they were looking for randomized controlled trials on adults who had pre- and post-study blood pressure data, and the studies had to have lasted longer than two weeks. The studies also had to have tested some form of green tea and its effects on blood pressure.

The various forms of green tea they allowed were green tea leaves, green tea extract, epigallocatechin-3-gallate (EGCG) and green tea catechins (a group of green tea antioxidants that includes EGCG). After weeding through almost 15,000 studies, 36 made the cut.

This study aimed to examine the relationship between green tea and blood pressure. Researchers also wanted to determine if there is an optimal dose of green tea that may help manage blood pressure. 

What Did This Study Find?

Taking all of the studies into consideration and combining their findings, researchers found that regular consumption of green tea in various forms was associated with an average of 1 mm/Hg reduction in both systolic (top number in blood pressure reading) and diastolic (bottom number) blood pressures. 

Because the studies included in this review and meta-analysis were all performed differently, researchers could not come to a conclusion regarding dose-response. In other words, they can’t say how much green tea and which form of it works best.

The 1 mm/Hg decrease in blood pressure is not clinically significant, say researchers, but because it is statistically significant, it shows promise. They concluded that green tea could be a complementary component to blood pressure treatment, but should not replace what is currently recommended for hypertension.

This systematic review and meta-analysis is limited due to the differences in how the included studies were conducted. Because of this, it cannot be said which forms of green tea and how much of each work best for lowering blood pressure. 

How Does This Apply to Real Life?

It’s easy to add green tea into your day, simply by brewing up a cup of it. If you’ve never had green tea, it’s a lighter, more delicate version of its sister, black tea. Green tea is also lower in caffeine than black tea. So while you won’t get the same level of caffeine buzz with green tea, it’s also one reason it may be good for your blood pressure, as substances that rev you up too much can increase your blood pressure.

Besides blood pressure, green tea may also help reduce inflammation, improve blood sugar and cholesterol levels, support brain health, aid digestion and reduce the risk of cancer. That’s a lot of benefits in those tea leaves! 

For best absorption of green tea’s plant compounds, it’s recommended that you drink it on an empty stomach. That’s not to say that your body won’t absorb any of green tea’s antioxidants if you have it with a meal, just that you’re likely to absorb more when there’s not food in your stomach. With that said, there’s another reason for this. The tannins in green tea can interfere with the absorption of plant-based iron (non-heme iron). This is an especially important point if you have anemia or tend to be prone to it. If you’re going to have green tea throughout the day, you’ll benefit more by sipping it between or before meals—we’re fans of having morning green tea before eating.

It’s also worth mentioning that if you’re going to be a regular imbiber of green tea, it may be prudent to use loose-leaf tea with a strainer. This is because some tea bags may contain microplastics, which can end up in your cup and ultimately in your body and brain.

As with anything, there is no one magic food that cures disease, including green tea for blood pressure. For a big picture view of diet for healthy blood pressure, consider trying our 30-Day DASH Diet Meal Plan for Beginners. It’s loaded with whole foods, like fruits, vegetables, whole grains, lean proteins and dairy, nuts, seeds, legumes and healthy fats. We slash the sodium by watching how much we use in recipes, and avoiding highly processed foods, including processed meats. 

Considering other lifestyle factors, it’s also important to move your body often, manage your stressors and get enough quality sleep. While this may seem overwhelming, the changes don’t have to be made all at once. Even small changes can be beneficial. For example, we previously reported that swapping just 5 minutes of sitting time with vigorous physical activity resulted in a measurable reduction in blood pressure. 

This will add up to even more benefits if you take 5-minute breaks throughout the day to do some vigorous walking, jumping jacks, burpees, push-ups—any movement that raises your heart rate. Vigorous activity is different for everyone, depending on your fitness level, so start where you’re at and over time, what used to be vigorous will become moderate. 

Our Expert Take

This systematic review and meta-analysis suggests that regularly ingesting some form of green tea may reduce systolic and diastolic blood pressure by 1 point each. Drink green tea on an empty stomach for the best antioxidant absorption. It’s also important to take a whole health view for blood pressure management, which includes eating a diet rich in whole foods and low in sodium, engaging in regular physical activity, managing what’s stressing you out and getting plenty of quality sleep.