Chlorogenic Acid – The Acid In Coffee With An Antioxidant Kick

Although much has been written about drinking coffee for its antioxidant benefits, my recent article about cocoa flavonoids made me wonder about the relationship between these compounds, and the antioxidants in coffee.  Turns out the primary antioxidant in coffee is chlorogenic acid, which was one I’ve never encountered.

Chlorogenic Acid

News about antioxidants usually focuses on flavanoid compounds typically found in fruits and teas.  These are some of the “classic” antioxidants.  By contrast, chlorogenic acid is not a polyphenol, but rather a plant phenol, whose starting blocks consist of caffeic acid and quinic acid.  As with most things in nature, caffeic acid is closely related to another commonly occuring acid in nature, cinnamic acid.

The “claim to fame” for antioxidants is their potential to protect against diseases thought to be rooted in free radicals.  Like most antioxidant research, testing on chlorogenic acid has shown the compound to have powerful antioxidant properties when evaluated in a test tube.  Direct studies on its antioxidant properties in people is less clear, since the exact amount of chlorogenic acid absorbed from food has been difficult to quantify.  Furthermore, during metabolism, the compound is believed to convert rapidly into its constituent components.  Even with those limitations, direct studies on the impact of chlorogenic acid on human health have shown this acid may promote the flow of bile and could reduce the risk of liver disease.  Other work has suggested chlorogenic acid may be associated with a reduced risk of type 2 diabetes and Parkinson’s disease.

In counterpoint, the picture isn’t all positive for chlorogenic acid.  Like most other phenolic compounds, it complexes with iron to inhibit its absorption, so its recommended for people with iron deficiencies to avoid consuming iron-containing foods with chlorogenic acid-containing foods to avoid this problem.  Studies have shown it is associated with increased plasma homocysteine levels, which is a strong marker for cardiovascular disease.  Furthermore, it has been proven to be an immune system suppressor.  Due to this, people following the Marshall Protocol, as a curative for chronic inflammatory disease, are recommended to reduce their intake of foods high in chlorogenic acid.

Food Sources Of Chlorogenic Acid

By far and away, the most abundant food source of chlorogenic acid in the average person’s diet is coffee.  It has been estimated that the average coffee drinker, consuming 3 cups of coffee per day, ingests about 1-gram of chlorogenic acid from that source alone.  This value isn’t substantially altered by the decaffeinating process.  Chlorogenic acid is also available as a dietary supplement in parts of Europe.  Although it is present is many plants, the levels are substantially lower in most other foods than in coffee beans.  Some of the foods higher in chlorogenic acid include:

Foods With Chlorogenic Acid

Sources

ARS-GRIN

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