Blueberries are widely popular fruit from the family of Ericaceae whose other members include bilbery and cranberry. Furthermore, they belong to the Vaccinium genus. Within the genus, there are three distinct groups of blueberries.
Highbush blueberries (picture below) are the most common type of blueberries and these are the most popular among consumers. They are native to North America and were exported into other parts of the world from here. They can grow up to 4 m in the wild, but in cultivation, they rarely exceed the height of 2 meters. Lowbush blueberries, commonly called „wild blueberries“, grow up to 30 cm above ground, but often stay even lower than that.
Their berries are smaller in size than highbush and are not so popular, so you will not find them in many supermarkets. And the third group of blueberries are the rabbiteye blueberries. This species grows in southern U.S.A. They can grow up to 6 meters in wild, but only 3 meters in cultivation. They are less cultivated than highbush blueberries.
The fruit is a small berry ranging in color from blue to purple-black and its surface is covered with a protective white waxy coating called the „bloom“. The taste ranges from sweet to tart. They are used in cuisines all around the world, from America to Europe and Asia.
However, their popularity is the biggest precisely in America where they are the second most-popular fruit, after strawberries. The season of blueberries in the north hemisphere is from May to October and in the south hemisphere from October to April. But in many countries, fresh blueberries are available year-round.
America is the biggest producer and consumer of blueberries in the world. Canada is the second largest producer, followed by South American countries like Chile, Argentina and Uruguay, and New Zealand.
History of blueberries
Although the fruit itself is small, the size of its history is big. It’s been said that blueberries have been around for nearly 13 000 years. Native Americans had been familiar with this plant a long time before the Europeans came along. According to the legend, they gave blueberries to the pilgrims to help them endure their first winter in the new land.
The Native American people would dry blueberries in the sun and put them into soups and stews or added them to meat. Or they would crush them into a powder and used it on meat as a preservative. Bluberries became a part of their folklore. They called them “star berries” because of the five-pointed star-like shape on the top of each berry. The berries, leaves and roots of the plant were used in medical purposes. At the same time in Europe people were using blueberry’s close relatives for medical purposes as well. They would make tea out of bilberry’s roots to help women during childbirth and used bilberry syrup for treating coughs.
Blueberries are low in cholesterol, saturated fat and sodium; high in dietary fiber and a very good source of vitamin C, vitamin K and manganese. But their true strength lies within the richness of phytonutrients.
The most abundant and important among these are anthocyanins (malvidin, delphinidin, pelargonidin, cyanidin, peonidin). They are the pigments which give blueberries, and other plants, that beautiful blue, purple and red color.
But other than these, there are many other significant phytonutrients in blueberries as well: hydroxycinnamic acids (coumaric, ferulic and caffeic acids), hydroxybenzoic acids (procatchuic and gallic acids), flavonols (kaempferol, myricetin, quercetin) and other phenol-related phytonutrients (pterostilbene, resveratrol). All of the mentioned function as both anti-inflammatory and antioxidants.
Research has shown that freezing blueberries does not damage their precious phytonutrients. Therefore, they can be preserved and consumed even in the off-season. However, they are damaged by cooking, so the nutritive value of fresh blueberries is slightly higher than of those which are prepared in a cooked recipe. Research has shown that organically cultivated blueberries are significantly richer in antioxidants, both anthocyanin and phenol, than those grown non-organically. So, if you have the chance, and want to maximize antioxidant benefits from blueberries, use the organic ones.
Blueberries are considered a superstar among the healthy food. In addition to beneficial effects on body systems which require special protection from oxidative stress, like the cardiovascular system, intake of blueberries shows the same beneficial results in the entire body, in absolutely all body systems. For example, there is evidence of antioxidant protection in muscles damaged by excessive exercise, in nervous system, in blood sugar regulatory system and every other system in the body.
The beneficial effect on cardiovascular system is multiple. The antioxidants from blueberries protect the cells in blood vessel walls and also the cholesterol in blood from oxygen damage which could lead to clogging of the blood vessels. Beside this, they support a healthy blood pressure. In individuals who have high blood pressure, regular blueberry consumption reduces the pressure, and in people with normal blood pressure, it helps maintain it healthy.
Nerve cells are sensitive to oxidative stress because they have a high risk of oxygen damage. They require a balanced oxygen metabolism in order to function properly. By lowering the stress, antioxidants from blueberries help nerve cells to work properly. Studies have shown that regular intake of blueberries can improve memory and other cognitive functions and slow down and postpone degradation of nervous system in elderly people.
Other health benefits
It has been shown that blueberries have a favorable effect on people diagnosed with sugar regulation problems, such as patients with metabolic syndrome, insulin resistance and type 2 diabetes. The nutrients from blueberries help in maintaining the balance of blood sugar levels, preventing it to spike too high or drop too low.
The retina of the eye is another part of the body that is at the higher risk of oxidative stress. Blueberries protect retina from oxidative damage and from damage from sunlight as well.