Review · Food & nutrition research · 2017

Anthocyanins as food colours and their health effects

What it found

In lab tests, animals and some human trials, anthocyanins acted as antioxidants and showed protective effects against heart disease, cancer, diabetes, obesity and nerve damage.

Human trials found mixed results for heart health and some benefit for blood sugar and eye conditions.

What they found

Studies in people

Heart health in people

One trial found that eating anthocyanin-rich strawberries for one month improved lipid profile and platelet function in healthy volunteers. But another trial found that 500 mg per day of elderberry extract for 12 weeks was ineffective in reducing heart disease risk in healthy postmenopausal women.

Blood sugar in people

In a 24-week trial of 58 diabetic patients, those who took two anthocyanin capsules (160 mg) twice daily from bilberry and blackcurrant had significantly lower fasting blood sugar and insulin resistance, and higher levels of certain blood markers, compared with placebo.

Eye health in people

In 132 patients with normal tension glaucoma, taking two bilberry anthocyanin capsules (60 mg each) daily improved visual function. In 19 patients with open-angle glaucoma, 50 mg per day of blackcurrant anthocyanins for 24 months increased eye blood flow but did not change eye pressure.

Animal and lab studies

Cancer in animals and cells

In rats, black raspberry anthocyanins reduced signs of oesophageal cancer. In mice, purple-fleshed sweet potato suppressed formation of abnormal colon crypts. In cancer cells grown in the lab, anthocyanins from blueberry, black rice and other sources inhibited growth and spread.

Obesity in animals

Obese mice fed cyanidin-3-glucoside from purple corn for 12 weeks lost body weight and had less fat tissue. Another study found that obese mice fed Cornelian cherries containing anthocyanins for eight weeks had a 24% decrease in weight gain.

Other findings

Colour and stability

Anthocyanins appear red in acidic conditions and turn blue as pH rises. Their colour and stability are also affected by light, temperature and structure. They are less stable at higher temperatures.

What the authors conclude

“Although most red wine anthocyanins have low bioavailability, increased consumption of these anthocyanins may help to increase the efficacy. However, the side effects of overconsumption of anthocyanin remain unknown.”
Khoo HE, Azlan A, Tang ST, Lim SM, 2017

Also in their conclusions

  • They say that anthocyanins are potential pharmaceutical ingredients that give various beneficial health effects.
  • They state that the health effects are due to their potent antioxidant properties.
  • They advise that more research is needed, especially on the side effects of overconsumption, which remain unknown.

How it was done

The authors wanted to review how anthocyanins are used as natural food colours and what evidence exists for their health effects, since synthetic food dyes have raised safety concerns.

They gathered and reviewed studies on anthocyanins from fruits, vegetables and flowers. These included cell studies, animal experiments and human trials, looking at how these pigments are extracted, how stable they are, and their effects on health.

What it can’t tell you

  • Many of the findings come from cells or animals, so they cannot show what happens in people.
  • Some human trials were small or lacked control groups, so their results may not be reliable.
  • The long-term effects of eating anthocyanins are not known.

The paper

Title
Anthocyanidins and anthocyanins: colored pigments as food, pharmaceutical ingredients, and the potential health benefits
Type
ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
Evidence
Studies in people · animals · lab
Summarised from
Full text
Cite
Khoo HE, Azlan A, Tang ST, Lim SM (2017). Anthocyanidins and anthocyanins: colored pigments as food, pharmaceutical ingredients, and the potential health benefits. Food & nutrition research. doi:10.1080/16546628.2017.1361779Free full textPubMed 28970777DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error