What Is Anthocyanin? | Health Benefits, Side Effects & Dosage

Have you ever wondered how berries get their varied and bright colours?

The answer is all in the pigment which lies in their skin!

These richly collected cells in the skin of berries which give the skin their bright colours, are the home for a variety of biological compounds. One of which is a specific flavonoid, which we will discuss here as a source of a plethora of health benefits.

Flavonoids (or bioflavonoids) are a group of molecules created during plant metabolism. In fact there are 6,000 different types of these metabolites (1). There are a number of different health benefits ascribed to these molecules including anti-oxidant and anti-inflammatory properties.

This article will examine one particular member of this group, one which has even been deemed the most important of the flavonoids (2); and the one making up the key structure of the pigment in fruits.

This article will discuss Anthocyanin and how it can boost your health and performance.

What Is Anthocyanin?

In truth, anthocyanin is similar to but not exactly a flavonoid. Instead it is part of the flavonoid group of phytochemicals (naturally occurring chemicals in plants).

There are about 17 anthocyanidins in total, with six (cyanidin, delphinidin, petunidin, peonidin, pelargonidin, and malvidin) having the most importance to humans (3-4).

They occur naturally in a variety of fruits and vegetables, but are particularly concentrated in a number of berries (e.g. strawberry, cherry, raspberry, blueberry). The anthocyanidins exist as the pigment which gives berries their colour (5-6); and as such are normally sufficiently consumed by most people (7-8).

Historically they have been utilised for remedies of a diverse number of diseases, including high blood pressure, vision disorders and infections just to name few (179-10). As such, proliferating their reputation as all around super supplement.

Oral consumption of anthocyanin in fruit, extracts or supplements has proved to be effective in preventing or treating such diseases (11-13). .

How Do Anthocyanins Work?

Oxidative stress is a state where the quantities of free radical atoms (reactive oxygen species) are greater than the capacity of anti-oxidants (compounds which delay or inhibit oxidation by free radicals). This imbalance leads to oxidation of proteins, lipids and even DNA (14).

The degree of anti-oxidant activity of anthocyanins have been widely confirmed (15-18).

However, the ability of anthocyanins to counteract reactive oxygen species is different between one type to another, and is wholly dependent upon each compound’s chemical structure (19). Each type of anthocyanin may react differently to a different type of free radical, which some what leads to differing research results.

Unfortunately some of the positive experimental (in vitro) studies showing high anti-oxidant capacity (20-23) are not entirely supported by human food trials (24).

However, it is possible that  very  low  concentrations  of  anthocyanins  may also modulate  cell  signalling and other  biological processes  by  non-antioxidant mechanisms which may explain the difficulty in observing anti-oxidant effects in human trials.

Studies have also shown that anthocyanins may have an anti-inflammatory role via a number of cellular mechanisms (5).

Anthocyanins inhibits the  biological  activity  of  some  pro-inflammatory proteins called cytokines  by  suppressing  specific cellular signalling pathways  (20,25).

For example, they can work to inhibit the pro-inflammatory enzyme, cyclooxygenase-2 (COX-2) which is often responsible for pain (26-27).

In truth it is the combined anti-oxidant and anti-inflammatory cellular activity which facilitates the clinical uses of anthocyanin when treating disease.

Anthocyanin | Health Benefits?

However, whilst some studies and media publications concentrate solely on the anti-oxidant and anti-inflammatory benefits of Anthocyanin, it is apparent in the research that other mechanisms are potentially as responsible for the health benefits described (13,28-30).

Some of these additional biological effects include protection against:

- Reactions which break down DNA

- Hormone-dependent disease development (oestrogen activity)

- Lipid peroxidation (lipid breakdown)

- Fragility of capillary blood vessels (12,33-36)

It is the combination of these mechanisms which allows arthocynanins to be beneficial across so many disease states. Below we shall examine some of the specific health issues where anthocyanins have been deemed beneficial.

Clarity of vision, or how well defined you can see an image (visual acuity), can be improved through administration of anthocyanin (37). However, this is not the only part of vision which can be improved. The ability to see in the dark (night vision) is also enhanced through the provision of anthocyanin (37).

Interestingly researchers have also suggested a relationship between anthocyanins and weight loss (13). This study provided mice a high fat diet in combination with anthocyanins. Their results found an effective inhibition of body weight and fat (adipose) tissue gain.

They also saw the prevention of a number of metabolic disease factors including hyperglycaemia (high blood sugar) and hyperinsulinaemia. This provides evidence of anthocyanins role in management of obesity and metabolic syndrome.

A final health related benefit of anthocyanin is through modulation of the nervous system to boost cognition and memory, whilst helping to prevent age related neurodegeneration.

Experiments with mice show both enhanced cognitive function and reduction in lipid peroxidation in brain tissues(46). This is supported by evidence showing that administration of high arthocynanin content blueberry extract leads to effective reversal of neurodegenerative memory and motor functions (47).

Anthocyanin & Athletic Performance

The question remains then, how can arthocynanin use its various properties to assist athletic performance in healthy individuals?

The larger group of bioflavonoids have been shown to influence the oxidation process in muscles during endurance exercises with a resulting increase in maximal oxygen consumption (VO2 max) (48-50). This has been postulated to be due to an increase in the number of mitochondria inside the muscle cells.

There is also evidence that these compounds can reduce muscular damage and post exercise soreness, whilst simultaneously improving neuromuscular function (51-52) and strength (53).

1) A recent study from the International Journal of Preventative Medicine underwent a double-blind, randomised controlled trial to examine the effect of anthocyanin supplementation on parameters of exercise performance (2). These researchers took 54 female and male athletes and compared the intake of 100mg of anthocyanin per day to 100mg of placebo for a period of 6 weeks.

During this period the subjects performed a training regime 3 times per week of cycling and running at an intensity of 60-80% of their target heart rate. Their results shows that VO2 max made significant increases in the anthocyanin group beyond any change in the placebo group (p? 0.0001). Thus indicating that supplementation with this particular compound shows specific benefits in endurance based exercise training!

2) Separate animal model experiments support these findings indicating a relationship between anthocyanin supplement consumption and muscle growth and exercise capacity.

For example, a 7 week period of high intake in rats shows higher body weight and muscle growth, alongside increased swimming time to fatigue, compared to controls (54). Also, studies examining products which have a high anthocyanin content (as opposed to just anthocyanin supplementation) also indicate similar exercise related benefits.

3) Studies on cherry and blueberry juice (rich in anthocyanin) show beneficial effects on muscle damage and improved recovery following eccentric exercise (55-61). Alternately, Montmorency cherries (again high in anthocyanin content) were investigated to see their benefits on unilateral leg exercise induced muscle damage and function (62). In this study of 10 trained male athletes, a cherry extract supplement was examined.

Each participant underwent 10 sets of 10 single leg extensions at 80% of one repetition maximum (1RM) before and after 2 weeks of supplementation. Their results indicated that maximum voluntary force recovery was faster in the high anthocyanin cherry extract group, compared to a standard fruit concentrate.

Showing an improvement in muscle recovery particularly in the supplement which had high concentration of anthocyanin. It is thought that such muscular benefits are likely to be due to the increase anti-oxidant capacity for these athletes (63).

Anthocyanin | Side Effects

Due to the long history of consumption of foods which have a high content of anthocyanin (different berries for example); such flavonoids are generally regarded as safe and well tolerate in humans (64).

A large analysis of 133 randomised controlled trials examined the safety of flavonoids (including anthocyanin) and failed to indicate any adverse effects or toxicity issues of anthocyanin in particular (65).

It is worth noting that as a group flavonoids may have issues with toxicity dependent upon the type, dose and duration of intake (66)- particularly in high risk groups such as the elderly (67).

However, no such issues were indicated for anthocyanin in this study.

Anthocyanin | Dosage

The daily intake of anthocyanin is relatively high across the population at 500mg to 1g (68).

However, athletic and health related benefits require only an additional 100mg to boost anti-oxidant and anti-inflammatory capacity (2).

Take Home Message

So ends our whistle-stop tour of the incredible anthocyanin compound.

From, what is innately a biproduct of natural evolution, a compound flourished which can boost anti-oxidant and anti-inflammatory function, whilst also modifying cellular signalling, to aid health and physical performance.

Therefore, whether you want to improve your vision, takes steps to help prevent against aging and disease, or even enhance your endurance performance, anthocyanin may be worth a look!

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