The Hydroxycinnamic Acids Explained

The Hydroxycinnamic Acids


The hydroxycinnamic acids are a group of phytonutrients (plant based chemical compounds that have numerous health benefits in the human body but are not classed as essential nutrients). They are mainly found in coffee but can also be sourced from fresh fruits and vegetables.

Whilst the hydroycinnamic acids are not believed to be essential for human survival, they do have a number of important health benefits. Apart from coumarin, they are all potent antioxidants which keep your body’s cells safe from harmful free radicals (dangerous substances that are released into the body’s cells during oxygen related reactions). In addition to this, the hydroycinnamic acids act as anti-inflammatories (substances that prevent unnecessary inflammation within your body), keep your blood healthy, prevent cancer and much more.

In this article I will be expanding on this topic and taking a detailed look at 4 of the main hydroycinnamic acids:


A cup of black coffee.History:- People have been aware of caffeic acid as far back as 400 B.C. However, it is not known exactly when caffeic acid was discovered or who made this discovery.

Health Benefits:- Caffeic acid is highly protective in the human body and acts as an anti-inflammatory and an antioxidant. It can also prevent cancer and diabetes.

Recommended Daily Allowance (RDA):- There is currently no RDA for caffeic acid but studies suggest consuming between 100 milligrams (mg) and 500mg of this hydroycinnamic acid will allow you to activate its health benefits.

Food Sources:- Coffee is the main food source of caffeic acid with 100 millilitres (ml) of this hot beverage providing you with between 18mg and 88mg of this hydroycinnamic acid. Apples, artichokes, basil, cabbage, cauliflowers, kale, oregano, pears, radishes, thyme and turnips are also good food sources of caffeic acid but the exact amounts they contain is not known.

Overdose Symptoms:- Caffeic acid is believed to be safe and have no negative side effects. However, drinking large amounts of coffee (the main source of caffeic acid) can cause a caffeine overdose. The amount of caffeine that causes an overdose depends on the person. Generally, consuming between 300mg and 700mg (3-7 average cups of coffee) will lead to mild overdose symptoms such as excitement, increased heartbeats, increased urination, muscle twitching, nervousness, restlessness, thirst and sleeping difficulties. Consuming more than 700mg of caffeine (8 or more average cups of coffee) will lead to more serious overdose symptoms which include confusion, convulsions, disorientation and loss of consciousness.

Deficiency Symptoms:- Caffeic acid is not classed as an essential nutrient so there are no reported deficiency symptoms associated with its consumption.


A whole and chopped apricot on a white background.History:- Coumarin was isolated by A.Vogel in 1820 and later synthesised in 1868 by William Henry Perkin.

Health Benefits:- Coumarin has a lot of potential health benefits in the human body but further studies are required before these can be confirmed. Provisional evidence suggests that it may act as an analgesic (a substance that relieves pain), an anti-inflammatory and an antisceptic (a substance that prevents the growth of disease causing microorganisms). It may also prevent arrhythmia (irregular heartbeats), cancer, osteoporosis (reduced bone mineral density), the human immunodeficiency virus (a virus that is often abbreviated to HIV and causes acquired immunodeficiency syndrome (AIDS) which ultimately destroys the immune system) and high blood pressure. Finally, it may protect the capillaries from damage and treat ashthma (a respiratory disorder that causes breathing difficulties).

RDA:- There is currently no RDA for coumarin but the European Food Safety Authority (EFSA) has established a tolerable daily intake (TDI) of 0.1mg per kilogram (kg) or bodyweight.

Food Sources:- The exact amount of comarin found in foods is not known. However, apricots, cherries, cinnamon, strawberries and tonka beans are all top sources of this hydroxycinnamic acid.

Overdose Symptoms:- Natural coumarin has no reported side effects. However, it can be very dangerous when artificially added to foods or other products (such as perfume) and cause bruising, excessive bleeding, interference with blood thinning medications, kidney damage, liver damage and lung cancer.

Deficiency Symptoms:- Coumarin is not classed as an essential nutrient so there are no reported deficiency symptoms associated with its consumption.


3 cups of coffee on a wooden table.History:- Chlorogenic acid was discovered in 1932 but it is not known who made this discovery.

Health Benefits:- Chlorogenic acid is 1 of the most powerful hydroycinnamic acids and has a wide range of health benefits in humans. It is a powerful antioxidant that can also prevent atherosclerosis (a condition where hard plaques form in your artery walls, restrict the flow of blood and ultimately increase your heart disease risk), prevent cancer and prevent diabetes. In addition to this, it can reduce blood levels of low density lipoprotein (LDL) cholesterol (a type of cholesterol that causes blockages in the arteries and increases your heart disease risk), reduce your heart disease risk (by preventing atherosclerosis and reducing blood levels of LDL cholesterol) and support weight loss (by forcing your body to use fat for energy).

RDA:- There is currently no RDA for chlorogenic acid but most studies have used doses between 60mg and 185mg per day (the equivalent of 1 or 2 average cups of coffee) to take advantage of the health benefits listed above.

Food Sources:- Coffee is the richest source of chlorogenic acid and contains between 35mg and 175mg of this hydroycinnamic acid per 100ml. Some other good chlorogenic acid foods include apples, blueberries, pears, sunflower seeds, tea and tomatoes but the exact amounts they contain is not known.

Overdose Symptoms:- Chlorogenic acid has no reported overdose symptoms. However, drinking large amounts of coffee (the main source of chlorogenic acid) can lead to the caffeine overdose symptoms discussed earlier in this article.

Deficiency Symptoms:- Chlorogenic acid is not classed as an essential nutrient so there are no reported deficiency symptoms associated with its consumption.


A selection of fruits and vegetables wrapped in a heart shaped tape measure.History:- Ferulic acid was first isolated in the early 1900s but there is very little other information available on its discovery.

Health Benefits:- Ferulic acid is well known for its skin boosting properties and provides significant antioxidant protection to the skin cells. In addition to this, early studies indicate that ferulic acid may prevent bone degeneration, prevent cancer, prevent negative hot flushing symptoms in menopausal women, protect the skin cells from ultraviolet (UV) damage, reduce blood levels of LDL cholesterol and treat diabetes. However, further evidence is required before these potential health benefits can be confirmed.

RDA:- There is currently no RDA for ferulic acid.

Food Sources:- Some level of ferulic acid can be found in most plant based foods. The exact amounts they contain are not known but some of the best food sources include apples, asparagus, carrots, coffee, oranges, peas, pineapples and whole grains.

Overdose Symptoms:- There are currently no overdose symptoms associated with ferulic acid consumption. Studies on animals have used doses as high as 1,500mg per day and reported no adverse side effects.

Deficiency Symptoms:- Ferulic acid is not classed as an essential nutrient so there are no reported deficiency symptoms associated with its consumption.


There is still a lot of research to be done on the role hydroxycinnamic acids have to play in the human body. However, the available evidence is very promising and suggests that they can protect your cells from damage, disease and much more. So enjoy 1 or 2 cups of coffee each day, fill up on fruits and make sure your meals are rich in vegetables to start enjoying all the benefits that the hydroxycinnamic acids have to offer.

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  1. Edet Itighise says

    Thanks for the article. It is an eye – opener negating the view of others kicking against consumption of coffee cos of caffein.


    Tom Reply:

    Glad you liked the article Edet. I find quite a lot of my research on this website challenges my existing opinions of certain foods.


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