What are Polyphenols and why should you eat them?

Learn about these powerful plant antioxidants, what they do in your body, and what foods you need to eat to get them.

Many of us are aware that certain foods, such as berries or green tea, are beneficial to our health. But what is the key to their health benefits? Polyphenols. These are compounds that protect the body against oxidative stress.

How do polyphenols work in the body?

Some popular polyphenols include epigallocatechin gallate (EGCG) in green tea and resveratrol in grapes and wine. Many of them act as antioxidants in the body, which means they can protect against environmental hazards like UV damage and pollution. Polyphenols offer several health advantages in addition to their antioxidant action. Some studies strongly suggest that polyphenol-rich diets may help prevent the development of some malignancies, cardiovascular illnesses, diabetes, and neurological disorders.

What foods are highest in polyphenols?

Polyphenols are abundant in many fruits and vegetables, but they are also present in beans, grains, and soy. This season, look for polyphenol-rich fruits and vegetables including blueberries, cherries, strawberries, blackberries, and spinach. Polyphenols can also be found in a cup of green or black tea, coffee, and even dark chocolate.

Polyphenols and heart disease

It's no secret that eating lots of fruits and veggies is good for your heart. Numerous studies have connected these foods' greater polyphenol content to a range of cardiovascular benefits. Pomegranate juice, for example, has polyphenols that help minimise oxidative stress and protect platelets from clumping together. According to a study published in The Journal of Nutrition, cocoa consumption lowers systolic blood pressure and LDL levels while raising HDL, or "good" cholesterol. Additionally, cocoa promoted flow-mediated dilation, which increased blood flow through the arteries.

A research published in the British Journal of Nutrition discovered that a greater polyphenol consumption was directly related to a decreased risk of type 2 diabetes in an adult population in Eastern Europe. While phenolic acids and stilbenes had a role in this connection, the advantages were predominantly due to flavonoids (a type of polyphenol), according to the study.

 Bottom line

Polyphenols are powerful plant-based chemical compounds that have anti-oxidative and regenerative capabilities. Get the benefits of polyphenols by consuming a variety of colourful fruits and vegetables, green tea, and dark chocolate.  Aim for 5 servings of more per day of fruits and vegetables.

Sources:

Moyle, C. W. et al. Potent inhibition of VEGFR‐2 activation by tight binding of green tea epigallocatechin gallate and Apple Procyanidins to VEGF: Relevance to angiogenesis. Molecular Nutrition & Food Research 59, 401–412 (2015). 

Grosso, G. et al. Dietary polyphenol intake and risk of type 2 diabetes in the Polish arm of the health, alcohol and psychosocial factors in Eastern Europe (HAPIEE) study. British Journal of Nutrition 118, 60–68 (2017). 

Ried, Karin et al. “Effect of cocoa on blood pressure.” The Cochrane database of systematic reviews vol. 4,4 CD008893. 25 Apr. (2017).

Pandey, Kanti Bhooshan, and Syed Ibrahim Rizvi. “Plant polyphenols as dietary antioxidants in human health and disease.” Oxidative medicine and cellular longevity vol. 2,5 (2009): 270-8. doi:10.4161/oxim.2.5.9498

Spencer JP, Abd El Mohsen MM, Minihane AM, Mathers JC. “Biomarkers of the intake of dietary polyphenols: strengths, limitations and application in nutrition research.” Br J Nutr. 2008;99:12–22.