Polyphenols are a type of natural compound found in many plant-based foods.
They have gained attention in recent years due to their potential health benefits.
In this article, we will explore what polyphenols are, their benefits for health, and which foods are high in these compounds.
What are polyphenols?
Polyphenols are a group of compounds that are widely distributed in plant-based foods, such as fruits, vegetables, grains, and herbs. They are known for their antioxidant properties and can be categorized into different classes based on their chemical structure.
Some common types of polyphenols include flavonoids, phenolic acids, and lignans. These compounds play important roles in protecting plants from environmental stressors and may also offer health benefits to humans who consume them.
Epigallocatechin gallate (EGCG) found in green tea and resveratrol present in grapes and wine are among the popularly known polyphenols.
What are the different types of Polyphenols?
Polyphenols are a diverse group of phytochemicals that are naturally found in plants.
There are more than 8000 different types of polyphenolic compounds (1), including:
- Flavonoids: These are the most common type of polyphenols and can be further divided into subcategories such as flavonols, flavanones, flavones, isoflavones, anthocyanins, and catechins. Flavonoids are found in many fruits, vegetables, and grains.
- Phenolic acids: These are another major class of polyphenols that include compounds such as ellagic acid, gallic acid, and caffeic acid. Phenolic acids are found in many fruits, vegetables, and nuts.
- Stilbenes: Resveratrol is a type of stilbene polyphenol that is found in grapes, berries, and peanuts.
- Lignans: These are polyphenols that are found in high concentrations in flaxseeds, sesame seeds, and whole grains.
- Curcuminoids: Curcumin is a type of curcuminoid polyphenol that is found in turmeric.
- Tannins: Tannins are a type of polyphenol that is found in tea, coffee, and wine.
- Others: There are many other types of polyphenols that include compounds such as lignins, stilbenoids, and coumestans. These are found in a variety of plant-based foods and beverages.
What are the potential health benefits of polyphenols?
Polyphenols are known for their antioxidant and anti-inflammatory properties, which can help protect the body against damage from free radicals and chronic inflammation.
Studies have also shown that polyphenols may have benefits for cardiovascular health, including reducing the risk of heart disease and stroke (2).
In addition, some polyphenols have been found to have anti-cancer properties, although more research is needed to fully understand their potential in this area.
Overall, consuming a diet rich in polyphenols may help support overall health and wellness.
A randomized trial was conducted with 102 hypertensive participants, where they were randomly assigned to either a high-polyphenol or a low-polyphenol diet, with 51 participants in each group (3).
The high-polyphenol diet included six servings of fruits and vegetables, mainly berries, and 50 grams of dark chocolate.
The participants followed their respective diets for 12 weeks, and the group on the high-polyphenol diet showed significant improvements in vascular function.
However, it is important to note that this study alone cannot conclude that polyphenols were solely responsible for the observed benefits.
Other beneficial compounds, such as vitamins and minerals, found in fruits, vegetables, and dark chocolate, could have also contributed to the observed effects.
Note: Polyphenols are believed to have potential health benefits, as suggested by various studies. However, there is currently no concrete evidence from large, long-term studies that can provide conclusive proof of these benefits.
Which foods are high in polyphenols?
Polyphenols are found in a wide variety of plant-based foods.
Some of the richest sources of polyphenols include fruits like berries, apples, and grapes, as well as vegetables like spinach, kale, and broccoli.
Legumes like beans and lentils, as well as nuts and seeds, are also good sources of polyphenols.
In addition, many herbs and spices are rich in polyphenols. Some of the most polyphenol-rich herbs and spices include cinnamon, ginger, and turmeric.
Here you can find the list of foods that have higher amounts of polyphenols
Frequently asked questions and answers about polyphenols
What are the recommended daily intake of polyphenols?
There is no specific recommended daily intake for polyphenols, but incorporating a variety of polyphenol-rich foods into your diet can help ensure that you are getting adequate amounts of these compounds.
Can you consume too many polyphenols?
While it is generally safe to consume polyphenols from dietary sources, taking high doses of polyphenol supplements may cause side effects in some people.
Can polyphenols cause side effects?
Polyphenols are generally considered safe, but consuming large amounts of some polyphenols, such as catechins found in green tea, may cause digestive upset or other side effects in some people.
Polyphenols are a diverse group of compounds found in many plant-based foods.
They offer numerous potential health benefits, including antioxidant and anti-inflammatory properties, as well as benefits for cardiovascular health and cancer prevention.
By incorporating a variety of polyphenol-rich foods into your diet, you can help support your overall health and well-being.