Blueberries belong to genus Vaccinium species. They are small fruit-shaped berries and are blue-black in color. They have originated from northern Europe and North America (1). The blue color is because of the anthocyanins which increase in content as blueberries ripen. Anthocyanins are responsible for colors such as red, blue, and purple in berries (2).

There is growing evidence that blueberries promote health because of the phytochemicals present in them. Among the phytochemicals present in blueberries anthocyanins have the most health-promoting effects. A daily moderate intake of 50 mg anthocyanins, one-third cup of blueberries would help in preventing the risk of diseases (2).

10 proven benefits of blueberries

1. Rich source of vitamin C

Blueberries are rich sources of vitamin C. Ascorbic acid as vitamin C is also called has several important functions in the body. Vitamin C is a strong antioxidant and apart from that enhances iron absorption from the diet.

2. Excellent source of antioxidants

Blueberries because of the presence of plenty of polyphenols exhibit antioxidant activity. Polyphenols in blueberries constitute both flavonoid and non-flavonoid types. Blueberries are one of the richest sources of anthocyanin flavonoids as about 60 % of the polyphenols are in the form of anthocyanins.

The health benefits of blueberries are mostly attributed to anthocyanins (2). Anthocyanins have antioxidant activity. Antioxidants reduce the risk of degenerative chronic diseases.

3. Diabetic-friendly berries

The glycaemic index of blueberries is 53 and glycaemic load per serving is 5 (3). Blueberries can be considered as low glycaemic food, therefore can be consumed by diabetics.

In a human study, the participants were given a daily supplementation of blueberry bio-actives in the form of 45 grams of freeze-dried blueberry powder. This was equal to about 2 cups of fresh whole blueberries. It was a 6 weeks study and it was concluded that blueberry powder enhanced insulin sensitivity in obese, nondiabetic, and insulin-resistant participants (4).

When the insulin sensitivity is increased the blood glucose levels are better regulated which is required in diabetes.

4. Heart friendly

In a review of work done on blueberries, it was stated that regular moderate, intake of blueberries reduced the risk of type 2 diabetes and cardiovascular diseases (CVDs) (2). The cardioprotective effects of blueberries were observed in another study on obese men and women (5).

Intake of anthocyanins was related to lowering of risk of hypertension which is one of the major risk factors of CVD’s (2).

5. Reduce blood pressure

In a study on postmenopausal women who have pre and stage 1 hypertension were given blueberries daily for 8 weeks. It was concluded that daily consumption of blueberries may reduce blood pressure and also arterial stiffness (6).

In a review of the literature, it was concluded that anthocyanin intake was linked to the reduction of hypertension (2).

6. Improvement in cognitive performance

Consumption of blueberries increased cognitive performance. These benefits were observed in children and adults (2). Blueberries can play an important role in improving memory.

7. Good for eyes

From the results of a study, it was concluded that anthocyanins of blueberries improve human retinal capillary endothelial function because of which they have the ability to prevent the progress of diabetic retinopathy (7).

8. Anti-inflammatory action

Blueberry anthocyanins exhibit anti-inflammatory activity (8). Blueberries could be used as natural therapeutic food for intestinal inflammation.

Because of the anti-inflammatory action blueberries probably can be used for other inflammatory problems too.

9. Antimicrobial activity

It was demonstrated in an experiment conducted that components of blueberries inhibit intestinal pathogens. This property of blueberries can be put to use in food safety (9).

10. Versatile blueberries

Blueberries are eaten as such, they are also used in dried form and are used in processed foods such as jams, jellies, ice creams, yoghurt, juices and several other foods. They are incredibly delicious and easy to use. You can even add the dried blueberries to your breakfast muesli and make it really tasty.

Final word

With so many health benefits it is no wonder that blueberries are called super food. With alarming rise of number of people with diabetes and CVDs it is important to consume foods that have components which help prevent or reduce the risk of these diseases. Include blueberries in moderation on a regular basis in your balanced diet.

References:

1. Nicoletti, A. M., Gularte, M. A., Elias, M.C., Santos, M.S.D., Ávila, B.P., Monks, J.L.F. and Peres, W. (2015) Blueberry Bioactive Properties and Their Benefits for Health: A Review, International Journal of New Technology and Research (IJNTR). Vol.1 (7).
   https://media.neliti.com/media/publications/263645-blueberry-bioactive-properties-and-their-bc039483.pdf

2. Kalt, W., Cassidy, A., Howard, L. R., Krikorian, R., Stull, A. J., Tremblay, F. and Zamora-Ros, R. (2019) Recent research on the health benefits of blueberries and their anthocyanins, Advances in Nutrition.
   https://academic.oup.com/advances/advance- article/doi/10.1093/advances/nmz065/5536953

3. Glycemic index (GI) and glycemic load (GL) values determined in subjects with normal glucose tolerance: 2008
   https://care.diabetesjournals.org/content/diacare/suppl/2008/09/18/dc08-1239.DC1/TableA1_1.pdf

4. Stull, A. J., Cash, K. C., Johnson, W. D., Champagne, C. M. and Cefalu, W. T. (2010) Bioactives in blueberries improve insulin sensitivity in obese, insulin-resistant men and women, The Journal of nutrition. Vol.140 (10).
   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3139238/

5. Basu, A., Du, M., Leyva, M. J., Sanchez, K., Betts, N.M., Wu, M., Aston, Ch.E. and Lyons, T. J. (2010) Blueberries Decrease Cardiovascular Risk Factors in Obese Men and Women with Metabolic Syndrome, The Journal of Nutrition. Vol. 140 (9).
   https://academic.oup.com/jn/article/140/9/1582/4600242
6. Johnson, S.A., Figueroa, A., Navaei, N., Wong, A., Kalfon, R., Ormsbee, L. T., Feresin, R.G., Elam, M. L., Hooshmand, S., Payton, M.E. and Arjmandi, B.H. (2015) Daily Blueberry Consumption Improves Blood Pressure and Arterial Stiffness in Postmenopausal Women with Pre- and Stage 1-Hypertension: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial, Journal of the academy of nutrition and Dietetics.115 (3).
   https://jandonline.org/article/S2212-2672(14)01633-5/fulltext

7. Huang, W., Yan, Z., Li, D., Ma, Y., Zhou, J. and Sui, Z. (2018) Antioxidant and anti-inflammatory effects of blueberry anthocyanins on high glucose-induced human retinal capillary endothelial cells, Oxidative Medicine and Cellular Longevity.
   https://www.hindawi.com/journals/omcl/2018/1862462/

8. Pereira, S.R., Pereira, R., Figueiredo, I., Freitas, V., Dinis, T.C., Almeida, L.M. (2017) Comparison of anti-inflammatory activities of an anthocyanin-rich fraction from Portuguese blueberries (Vaccinium corymbosum L.) and 5-aminosalicylic acid in a TNBS-induced colitis rat model, PLoS One . Vol. 12(3).
   https://www.ncbi.nlm.nih.gov/pubmed/28329021