9 health benefits of blueberries that make it a true superfood

Jill Bridges, SATI STAFF

Behold the humble blueberry. By day, it masquerades as a delicious fruit that can be used in a huge range of culinary applications from complex sauces to simply being added fresh to a summer salad. But by night it lives a dual life: giving our bodies a rich array of antioxidants, nutrients, fiber, and more.

In this way, blueberries live up to their reputation as a “superfood,” but the biggest difference between blueberries and other superheroes is that we have unmasked its identity through science. By probing the inner workings of blueberry nutrition through medical studies, treatment trials and more, scientists have uncovered just how beneficial blueberries can be.

And best of all, they taste amazing! A mild acidity, a healthy dose of sweetness and a unique flavor all contribute to a truly special fruit that people of all ages love to eat. If you have ever wanted to learn more about the bodacious blueberry, including the nine health benefits of blueberries and a bit of interesting facts, then read on for your complete guide to wonderful blue fruit.

What, exactly, is a blueberry

“Blueberry” refers to the fruit of several perennial flowering bush plants hailing from the Cyanococcus section of the Vaccinium genus. Cyanococcus plants are native to North America, meaning that no one except Native Americans had even seen blueberries until explorers set foot on the continent in the early 16th century.

However, blueberries have many cousins in Europe, the most similar of them being a fruit called the “bilberry.” Unlike blueberries, which grow with noticeable “crowns” poking from the bottom, billberries have a dent and a pattern that looks like a small gear inside. Other cousins of blueberry from the Vaccinium genus include huckleberries, cranberries, lingonberries.

Bilberries and huckleberries may be called “blueberries” by some, but there are only two varieties of authentic blueberries: highbush and lowbush. Both grow natively in acidic soil. Highbush blueberries (Vaccinium corymbosum) grow all throughout the eastern United States, going as far north as Quebec and Nova Scotia [1]. These plants have also been transported to Washington State and British Columbia for large-scale commercial growth.

Lowbush blueberries (Vaccinium angustifolium) grow through a similar range along the east coast, but prefer colder climates. They grow especially well in eastern Canada but can be grown as far south as Tennessee and North Carolina [2]. Lowbush blueberries are sometimes grown commercially, and they can be given the name “wild” blueberry even when grown under controlled farming conditions.

How blueberries are grown

Unlike some commercially grown crops, blueberry farms would look somewhat familiar to anyone who had a bush growing in their yard. Berries are grown in neat rows in acidic soil and given plenty of water. In the spring, tiny white blossoms emerge with a surprisingly perfumey scent. This scent attracts bees, which must pollinate each flower in order for it to turn into a berry.

Fertilized blueberry flowers turn into tiny, hard, green fruit. They take several months to mature, slowly growing larger and taking on a deep blue indigo hue. Waiting until the end of the summer produces the plumpest, sweetest berries. Berries are still harvested by hand in most operations. Some operations have moved to machine harvesting, like you can see in this video. More often than not, machine-harvested blueberries are sold frozen.

The story of how blueberries were first cultivated is actually quite interesting. Prior to the 1916, no one knew how to grow blueberries on a commercial scale. Each plant grew wild and had to be harvested by hand for local sale or personal use in the home.

The reason no one was successful at growing blueberries lay in how they tried to treat it like other plants. Most crops prefer mildly alkali soil and lots of nitrogen. Blueberries are the opposite! They prefer acidic soil, like the kind found on rocky hillsides or near swamps, and they do not need nearly as much nitrogen to grow.

A man named Frederick Coville first discovered the ideal conditions to grow blueberries, publishing his results in 1910 [3]. A woman named Elizabeth White read Coville’s report and invited him to her family’s cranberry farm in New Jersey, where wild blueberry bushes would grow near the edge of the bog. White also offered cash bounties on people who could identify bushes with the largest fruits.

Together, White and Coville helped cultivate the first hardy blueberry crossbreeds that could consistently produce the largest yield while tolerating tough weather conditions. They shipped the first container of non-wild blueberries to market in 1916, and they began to sell seedlings to farmers all across the country for expanded growth. Their efforts ensured that blueberry growing could be a lucrative business that provides us with the following nine health benefits of eating blueberries:

1. Jam packed with antioxidants

Antioxidants are natural substances that help our bodies combat harmful particles called free radicals. Free radicals refers to any molecule that has an odd, unpaired number of electrons. This imbalance causes the molecule to go out hunting for another electron to complete its pairs, stealing electrons and causing a chain reaction.

This type of reaction is called an “oxidizing” reaction, and it is the same thing responsible for causing metal to rust. In our bodies, having our molecules oxidized can cause serious damage, leading to cell death, abnormal behavior and even mutated, cancerous growth.

Antioxidant substances balance out free radicals and prevent oxidation, bringing along with them a host of positive benefits. And, just like the heading above suggest, blueberries can be jam packed with antioxidants! Research even shows that blueberries could have the highest concentration of antioxidants compared to any other fruit or vegetable commonly eaten [4,5].

The primary type of antioxidant found inside blueberries are flavonoids, a family of polyphenol compounds. Blueberries are very high in anthocyanidins in particular, which should not be surprising given that they are responsible for giving the berries their deep hue! Just a small handful of the berries (100 g) provides over a gram of these antioxidants, which include 49 mg of malvidin and 29 mg of delphinidin [6].

Blueberries also have a high concentration of proanthocyanidin antioxidants. These particular compounds help aid in blood clotting and can promote immune response, such as preventing a urinary tract infection. Over 150 mg of proanthocyanidins can be found in just one 100 g handful of berries, which is less than a cup!

2. Low calories, but full of nutrition

A cup of fresh blueberries can be a tasty snack all by itself, full of delicious sweetness and an interesting array of complex flavors. Yet, this snack has tons of the nutrients you need while still being low in calories and providing a bit of dietary fiber to help you feel full.

Consider a one cup portion of fresh blueberries, which equals about 145 grams, according to the USDA [6]. This portion has only 83 calories and under a half gram of fat. Yet, it contains over a gram of protein and 3.5 grams of dietary fiber — 14 percent of the daily recommended value!

A cup-sized portion also boasts 28.6 micrograms of vitamin K, enough to satisfy 36 percent of your daily intake [7]. You also get 14.4 mg of vitamin C, nearly a quarter of your daily value. You also get 25 percent of your daily recommended manganese and a fair amount of vitamin A, copper, riboflavin, vitamin E and vitamin B6.

3. Can protect against effects of aging and cancer

Superfoods like blueberries help fight cancer by defending against oxygen molecules.

The antioxidants in blueberries can prevent damage to our cells’ DNA. DNA damage can cause aging complications, but it can also lead to mutations and cancer. This damage is a part of normal life, but consuming antioxidants can diminish its effects, protect our DNA and sometimes even help prevent certain cancers.

A study of the effects of drinking blueberry juice mixed with apple juice every day found that participants resisted damage within their DNA by a significant factor. Total measured damage from oxidative reactions was reduced by 20 percent [8]. Similar studies observed protective effects from eating 300g of blueberries every day [9].

4. Helps you stay sharp and retain memory

The anti-aging effects of antioxidants include preserving some of the most essential tissues in the brain for memory and complex thought. In fact, the brain tends to hoard antioxidant substances in the highest concentrations in areas related to intelligence [10]. The anti-inflammatory tendencies of these compounds can also prevent damage associated with aging or neurodegenerative diseases like Parkinson’s [11].

One study tracked the effects of drinking blueberry juice daily in subjects with observed minor cognitive impairment. After a period of 12 weeks, individuals showed marked improvements in memory and cognitive function [12]. Another study followed the long-term effects of eating blueberries and strawberries regularly. The results indicated that factors of cognitive decline deteriorated more slowly, delaying it by a factor of 2.5 years total [13]!

5. Can help lower blood pressure

High blood pressure (hypertension) affects a third of the U.S. population and is a major risk factor for some of the country’s biggest leading causes of death [14]. Fortunately, eating certain foods like blueberries can help you manage your blood pressure and bring it lower.

A study of individuals with obesity found that eating just 80 grams of freeze-dried blueberries a day — around half a cup — lowered their blood pressure by four to six percent [15]. Overall, researchers involved in the study concluded that eating blueberries daily can have positive effects for the group of conditions known collectively as metabolic syndrome.

Similar studies found benefits for eating freeze-dried blueberry powder daily in sedentary men and women [16] as well as in postmenopausal women. Blood pressure improved, and marked improvements were observed in artery stiffness, another risk factor for heart disease.

6. Can improve cholesterol levels and protect against heart disease

Heart disease can arise from a host of risk factors, but one of the worst is the reaction of LDL lipoproteins (“bad cholesterol”) with oxidizing agents. When these lipoproteins become damaged through oxidation, they tend to leave cholesterol deposits along the walls of our arteries. The end result is decreased function and increased blood pressure [17].

Eating blueberries can help protect against these effects, preventing LDL lipoproteins from being oxidized and reducing the chances that cholesterol will become deposited where it should not be. Polyphenols, such as the flavonoids found in blueberries, can significantly reduce the likelihood and rate at which LDL lipoproteins become damaged [18].

A study mentioned above found that observed levels of LDL damage in plasma was reduced by 28 percent after just eight weeks of consuming a drink that contained 50 g of freeze-dried blueberry powder [15]. A similar study observed that eating blueberries with a meal, such as breakfast, could improve the body’s ability to resist oxidizing agents [19].

One of the few long-term studies on the matter found that eating a consistent diet of foods that have anthocyanins, like blueberries, is correlated with a significantly reduced risk of having a heart attack. The study followed 93,600 women for 18 years and measured the incidence rate of heart attacks. Those who ate foods like blueberries and strawberries had a 32 percent lower rate of heart attacks, providing a powerful case for adding more berries to your diet [20].

7. Can help the body prevent urinary tract infections

Urinary tract infections are painful, and they can be a common problem in aging populations, especially in women. Many people know about the healing effects of cranberries when it comes to urinary tract infections, but what they may not consider is how closely related blueberries are to their scarlet cousins.

Blueberry was shown to prevent urinary tract infections and it is one of the greatest home remedies for uti.

When comparing blueberry and cranberry juice, researchers found many of the same compounds and properties [21]. They theorized that the reason these juices can help with preventing bacteria from causing an infection had to do with their anti-adhesive properties. Drinking blueberry or cranberry juice prevents bacteria like E. coli from taking root on the mucus lining of the bladder and urinary tract, helping reduce the risk of colonization and infection.

8. May help certain individuals manage diabetes

Blueberries have a fair amount of sugar, with one cup (118 g) having nearly 15 grams of fructose sugar [7]. However, the dietary fiber content and anti-oxidizing compounds in blueberries slow digestion, giving it a medium-to-low measure on the glycemic index of 40-53 [22].

Put together, the result is a snack or tasty food addition that provides a fair amount of nutrition compared to its sugar count, allowing those with diabetes to consume blueberries in moderation provided they do not have any added sugar.

Additionally, blueberries may even have substances that help those with diabetes manage their symptoms. A study on lowbush (“wild”) blueberries extract mixed with fermented juice found that chemical agents inside them helped diabetics reduce insulin resistance and glucose metabolization [23]. Other studies confirm these results, even when the active substances were provided from leaf extracts [24], and various extracts from the roots, stems, leaves and fruits [25].

9. Could help you recover after a workout

Post-workout blueberry protein smoothie has all the nutrients and superfoods you need after your rigorous work out!

Bananas are a popular after-workout food, but perhaps people should start adding a handful of blueberries to the mix? Soreness following strenuous workouts can be partially attributed to inflammation and oxidative stress. The antioxidants in blueberries can help with both, improving recovery time while also possibly helping the body build stronger muscles.

One study observed female athletes after a series of intense leg workouts. Researchers concluded that drinking a blueberry smoothie before a workout can help reduce inflammation and oxidative stress while speeding the recovery of athletes overall [26].

The Sati line

The best, most nutritious blueberries are fresh and ripe. Based on evidence from several of the above research studies, freeze-dried blueberries can also provide similar levels of nutrition and antioxidant benefits. On the whole, frozen blueberries provide lower levels of vitamins, minerals, and sugars, but moderately higher levels of fiber [27]. These differences likely lie in fresh blueberries further ripening during transport.

Other types of blueberries — in sauces, smoothies, or as an added ingredient — can also provide the same level of nutrition but with one important catch. Individuals trying to eat a healthy diet, especially those trying to manage conditions like metabolic syndrome, should keep a close eye out for added sugar. Many preparations of blueberries, including frozen ones, can have tons of sugar added to it.

By the same token, be wary of simulated blueberries in products like cereal, oatmeal, ice cream and more. These “blueberries” are often actually made from food starch, artificial flavors and other ingredients, providing none of the nutritional value that actual blueberries can while loading you with carbs and sugar.

Fresh berries can be easily made into low-sugar jams and sauces when prepared at home. They can also form a tasty component of smoothies alongside leafy greens like spinach and other antioxidant-rich berries like strawberries. Raw blueberries can also be eaten plain as a snack or added to foods like salads, cereals and even pastas.

So go ahead and start adding blueberries to your diet! Whether eaten at breakfast, as a snack, added to a healthy dessert or incorporated creatively in a meal, they add a unique kick and come jam packed with nutrients, antioxidants and a host of health benefits!


References
  1. “Plants Profile for Vaccinium corymbosum (highbush blueberry).” National Resources Conservation Services. United States Department of Agriculture (2017)
  2. “Plants Profile for Vaccinium angustifolium (lowbush blueberry).” National Resources Conservation Services. United States Department of Agriculture (2017)
  3. Minick, Jim. “The Delicious Origins of the Domestic Blueberry.” JStor Daily (2016)
  4. Wofle, Kelly L., et al  “Cellular Antioxidant Activity of Common Fruits.” Journal of Agricultural and Food Safety. ACS Publications (2008)
  5. Prior, R. L., and G. Cao. “Analysis of botanicals and dietary supplements for antioxidant capacity: a review.” Journal of AOAC International. U.S. National Library of Medicine (2000)
  6. “Health and Healing Fact Sheets.” Berry Health Benefits Network. (2017)
  7. “Blueberries, raw Nutrition Facts & Calories.” Self Nutrition Diet. Condé Nast (2017)
  8. Wilms, Lonneke C., et al “Impact of multiple genetic polymorphisms on effects of a 4-week blueberry juice intervention on ex vivo induced lymphocytic DNA damage in human volunteers.” Carcinogenesis. Oxford University Press (2007)
  9. Del, C., P. et al  “A single portion of blueberry (Vaccinium corymbosum L) improves protection against DNA damage but not vascular function in healthy male volunteers.” Nutrition research (New York, N.Y.). U.S. National Library of Medicine (2013)
  10. Willis, L. M., B. Shukitt-Hale, and J. A. Joseph. “Recent advances in berry supplementation and age-related cognitive decline.” Current opinion in clinical nutrition and metabolic care. U.S. National Library of Medicine (2009)
  11. Subash, Selvaraju, et al. “Neuroprotective effects of berry fruits on neurodegenerative diseases.” Neural Regeneration Research. Medknow Publications & Media Pvt Ltd (2014)
  12. Krikorian, Robert, et al. “Blueberry Supplementation Improves Memory in Older Adults.” Journal of agricultural and food chemistry. U.S. National Library of Medicine (2010)
  13. Devore, Elizabeth E., Jae Hee Kang, Monique M. B. Breteler, and Francine Grodstein. “Dietary intakes of berries and flavonoids in relation to cognitive decline.” Annals of Neurology. Wiley Subscription Services, Inc., A Wiley Company (2012)
  14. “High Blood Pressure Fact Sheet.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, (2016)
  15. Basu, Arpita, et al. “Blueberries Decrease Cardiovascular Risk Factors in Obese Men and Women with Metabolic Syndrome.” The Journal of Nutrition. American Society for Nutrition, (2010)
  16. McAnulty, L. S., et al.  “Six weeks daily ingestion of whole blueberry powder increases natural killer cell counts and reduces arterial stiffness in sedentary males and females.” Nutrition research, U.S. National Library of Medicine (2014)
  17. Parthasarathy, Sampath, Achuthan Raghavamenon, Mahdi Omar Garelnabi, and Nalini Santanam. “Oxidized Low-Density Lipoprotein.” Methods in Molecular Biology, U.S. National Library of Medicine (2010)
  18. Khurana, Sandhya, Krishnan Venkataraman, Amanda Hollingsworth, Matthew Piche, and T. C. Tai. “Polyphenols: Benefits to the Cardiovascular System in Health and in Aging.” Nutrients. MDPI (2013)
  19. “10 Proven Health Benefits of Blueberries.” Authority Nutrition (2016)
  20. Cassidy, A., et al. “High anthocyanin intake is associated with a reduced risk of myocardial infarction in young and middle-aged women.” Circulation. U.S. National Library of Medicine (2013)
  21. Ofek, Itzhak, Ph.D. “Anti-Escherichia coli Adhesin Activity of Cranberry and Blueberry Juices — NEJM.” New England Journal of Medicine (1991).
  22. “Blueberries, raw Nutrition Facts & Calories.” Nutrition Data. Self (2017)
  23. Vuong, T., et al. “Fermented Canadian lowbush blueberry juice stimulates glucose uptake and AMP-activated protein kinase in insulin-sensitive cultured muscle cells and adipocytes.” Canadian journal of physiology and pharmacology. U.S. National Library of Medicine (2007)
  24. Abidov, M., A. Ramazanov, M. Jimenez, and I. Chkhikvishvili. “Effect of Blueberin on fasting glucose, C-reactive protein and plasma aminotransferases, in female volunteers with diabetes type 2: double-blind, placebo controlled clinical study.” Georgian medical news. U.S. National Library of Medicine (2006)
  25. Martineau, Louis C. “Anti-diabetic properties of the Canadian lowbush blueberry Vaccinium angustifolium Ait.” Science Direct. Phytomedicine (2006)
  26. McLeay, Yanita, et al. “Effect of New Zealand blueberry consumption on recovery from eccentric exercise-induced muscle damage.” Journal of the International Society of Sports Nutrition. BioMed Central (2012)
  27. Joy, Traci. “The Benefits of Blueberry Supplements.” LIVESTRONG.COM. Leaf Group (2015)