What are Flavonoids?
Flavonoids are a group of compounds that are made by plants and have a similar shape, chemical structure, to one another. Dietary flavonoids are the flavonoids found in the plants that we eat, including many fruits and vegetables. Higher intake of dietary flavonoids is associated with reduced cardiovascular disease and other chronic diseases. However, it is not yet known if dietary flavonoids themselves reduce the risk of certain diseases or not, since a lot of the studies on flavonoid-rich foods demonstrates a correlation with disease reduction and not a causal relationship.
Flavonoids are a large family of compounds and can be broken down into sub-classes based, again, on chemical structure. The specific subclasses and amounts of flavonoids found in a plant varies from plant to plant.
Subclasses and sources of flavonoids:
|Subclass of flavonoid||Common plant sources|
|Anthocyanidins||Berries, red cabbage, cherries|
|Flavonols||Onions, apples, tea|
|Flavones||Parsley, peppers (hot or sweet), celery|
|Flavanones||Citrus fruit – oranges, grapefruit, lemons|
|Flavanols||Tea, blueberries, cocoa|
*Red letters highlight differences in names of subclasses
What are Flavanols?
Flavanols, sometimes called flavan-3-ols, are a subgroup of the larger flavonoid group and are found in a variety of plant foods – including tea, berries, apples, and cocoa. There are four forms of flavanols that differ based on their chemistry. Find out more about the chemistry of flavanols.
What are Cocoa Flavanols?
Cocoa flavanols are naturally occurring dietary flavonoids found in the cacao plant. Based on a significant body of published research, consumption of cocoa flavanols has been shown to improve blood vessel function, thereby helping to support the health and function of the cardiovascular system. Cocoa flavanols is a term that is used to refer to flavanols and their related molecules, procyanidins. Procyanidins are compounds that are made by linking 2 or more flavanol molecules to form chain-like structures that commonly contain between 2 and 10 flavanol units.
Are Cocoa Flavanols Found in All Cocoa or Chocolate-Based Products?
No, not in consistent or guaranteed amounts. The fresh cacao bean, from the cocoa pod or "fruit," is naturally rich in flavanols. However, cocoa flavanols are easily destroyed during normal processing and not all cocoa-based products will contain significant levels of these beneficial compounds.
The Scientific Discovery: Nitric Oxide Not Antioxidant
Early scientific research looking at cocoa flavanols in a test tube suggested that they exerted health benefits through an antioxidant mechanism, but today we understand that this in fact is not the case. Subsequent research by Mars and its collaborators support that within the body, flavanols are themselves not potent antioxidants, and therefore unable to exert direct antioxidant effects in the body.
In the mid-1990s, Mars scientists observed an important relationship between cocoa flavanols and nitric oxide. Consumption of dietary flavanols is associated with an increase in nitric oxide production. Nitric oxide is a compound the body produces that triggers the muscles in the arterial wall to relax. This was underscored by the 1998 Nobel Prize in Medicine for research showing nitric oxide's central role in modulating cardiovascular health.