There are several factors that play a role in keeping your heart healthy, such as getting enough physical activity, not smoking, and managing stressTrusted Source.
The food you eat is also important when it comes to cardiovascular health. Past studies show foods rich in nutrients like fiber, omega-3 fatty acidsTrusted Source, antioxidants, potassium, and magnesium can offer heart-health benefits.
“Cardiovascular disease is a leading cause of death worldwideTrusted Source, and diet is one of the most important factors we can change to protect heart health,” Ana Rodriguez-Mateos, PhD, professor of human nutrition at King’s College London in the United Kingdom, told Medical News Today. “Making healthier food choices is therefore key to preventing heart disease.”
Rodriguez-Mateos is the senior author of a new study recently published in the journal BMC Medicine that adds to the list another nutrient with potential heart benefits polyphenols.
Researchers found that consuming foods rich in polyphenols — such as coffee, berries, walnuts, cocoa, and olive oil — may lead to improved long-term heart health.
Higher polyphenol metabolite levels, lower heart disease risk scores
For this study, researchers followed more than 3,100 adult participants of the TwinsUK cohort, who completed the EPIC-Norfolk Food Frequency Questionnaire, for more than 10 years.
Of the participant group, 200 were asked to give urine samples, from which scientists determined their polyphenol exposure by measuring their polyphenol-rich dietary score (PPS-D)Trusted Source and accompanying urinary metabolic signature (PPS-M).
Study participants also had their cardiovascular disease risk scores assessed through their atherosclerotic cardiovascular disease (ASCVD) risk score and HeartScore.
At the study’s conclusion, researchers found that metabolites in study participants’ urine samples confirmed that those with higher polyphenol metabolite levels also had reduced cardiovascular risk scores, as well as higher levels of HDL “good” cholesterol.
“[This] means that people who had more polyphenol breakdown products in their urine tended to show a more favourable cardiovascular profile,” Rodriguez-Mateos explained.
“Because this is an observational study, we cannot say polyphenols cause these differences, but the patterns support the idea that diets rich in polyphenol-containing foods may be linked with better heart health. Importantly, measuring metabolites in urine provides a more objective and accurate reflection of dietary intake than questionnaires alone,” she added.
More polyphenols linked to slower heart disease progression
In addition, researchers discovered that although heart disease risk naturally increases as we age, having a higher intake of polyphenol-containing foods was linked to a slower progression of risk over the 11-year follow-up period.
“Although everyone’s risk increased with age, those who consumed more polyphenols, or showed higher metabolite levels, had consistently lower predicted cardiovascular risk. This suggests that people with diets richer in polyphenol-containing foods tend to maintain a more favorable heart-health profile as they age, but again, no causal conclusions can be drawn.”
— Ana Rodriguez-Mateos, PhD
“Evidence from many randomized controlled trials shows that polyphenols can help blood vessels function better, as well as lower blood pressure, and improve blood lipid profiles,” Rodriguez-Mateos continued. “They appear to act through several mechanisms, including boosting nitric oxide availability in blood vessels, which helps them relax and support healthy circulation.”
“We plan to run a randomized controlled trial to test whether consuming a diet rich in polyphenol-rich foods can directly improve markers of heart health,” she added. “We are also developing new biomarker-based tools to measure diet more accurately and better understand how these compounds relate to long-term health.”
New knowledge on our understanding of polyphenols
MNT spoke with Cheng-Han Chen, MD, a board certified interventional cardiologist and medical director of the Structural Heart Program at MemorialCare Saddleback Medical Center in Laguna Hills, CA, about this study.
“These results add to our current understanding of polyphenols as natural compounds with anti-inflammatory and antioxidant properties that can improve blood vessel function and potentially be beneficial to heart health,” Chen, who was not involved in the research, commented.
“Cardiovascular disease is the leading cause of death in the United States. Research into the health effects of our daily diet will go a long way toward helping us control many of the known risk factors for heart disease, such as high blood pressure, high cholesterol, diabetes, and obesity,” he told us.
“Future research can further investigate whether some polyphenol-rich foods — such as tea, coffee, and certain nuts/berries — are more beneficial to heart health than others,” he added.
How to add more polyphenol-rich foods to diet
Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, offered her top tips for those who may want to start eating and drinking foods and beverages high in polyphenols.
“What I love most is that these benefits come from foods most people already know, such as berries, apples, citrus, nuts, beans, whole grains, herbs, spices, tea, and even dark chocolate,” Richard said.
“You don’t have to overhaul your whole diet — small, consistent shifts toward more plants, as accessible and available, can support your heart, gut, and brain starting today,” she advised.
Richard explained that people can add more polyphenols to their diet just by adding more plants to their plate. She suggested starting simple with one or two changes a day, such as:
adding berries to breakfast dishes
add spinach or peppers to egg dishes
tossing beans into soups
sprinkling nuts or seeds onto salads, or having them as a snack
choosing green or black tea instead of sweetened or diet soft drinks or syrup-laden coffee beverages
using herbs and spices like cinnamon, oregano, turmeric, or basil, which can be added to soups, casseroles, salads, sandwiches, and in sauteed, grilled, or baked entrees
reaching for fruits like apples, grapes, oranges, pears, and pomegranates, which are “easy-on-the go” snacks or desserts, and are great for the heart and brain, while their fiber and nutrient content supports gut function and the immune system.
“And yes, even a square of dark chocolate counts with a handful of nuts can be beneficial while satisfying that afternoon craving,“ said Richard.
“Polyphenol literally means ‘poly’- many, and ‘phenols’—a chemical structure (aromatic ring) in plant compounds that contains a phenyl group,” Richard detailed. “The translation — many protective compounds. Think of polyphenols as nature’s defense molecules — plants make them, and we benefit when we eat them.”
“Remember that meeting with a registered dietitian nutritionist (RDN) can help personalize and tailor your needs to your health goals based on your current health, lifestyle, preferences, activity level, current nutrition status, and more,” she added. “Work with your healthcare team or local search engine to find one that may be a good fit for you and your polyphenol needs.”