Blueberries are the popular name for the fruits of a forest shrub related to cranberries, cowberries, huckleberries, bilberries and other similar plants with edible fruits, all part of the genus Vaccinium. Despite the name, the fruit is not always blue in color.
They can have various shades of blue or even be fully black. All colors have in common a white layer with a waxy appearance that covers the surface and protects the berries.
The blueberry plant is an erect type of shrub that can exhibit significant variations in size. The height can be anywhere from 10 centimetres to an impressive 4 meters.
Leaves also have diverse sizes and shapes, from oval to lance-shaped. Their size is between 0.5-3.5 cm wide, with a length of 1 to 8 cm. Depending on the local climate, the leaves fall in the winter or survive during the entire year. The flowers have a shape similar to a bell and can have various colors: white, red, pink or even almost green.
The fruits are typical forest berries. They have a green color in their youth, turn red or purple afterwards and finally become blue or black when fully ripe. Their diameter is between 5 and 16 mm, with a small hole with a jagged edge, resembling a flared crown, at the top.
When fully ripe, the fruits are sweet but can be quite acid as well. Normally, the fruits become ripe in the middle of the year but the exact time depends on the local climate and altitude. North of the Equator, it typically happens between May and September.
The commercial cultivated varieties have become quite different from their wild counterparts, being much larger in size of both the plant and the fruits. The small shrubs that resemble the wild varieties are named “lowbush blueberries”, while the larger and more productive ones are known as “highbush blueberries”.
Blueberries are considered part of what scientists call the world’s “super foods”, because of their very high content of antioxidants. Modern research has proved that free radicals have the most important effect on aging and the various diseases associated with it. Since blueberries have one of the highest concentration of antioxidants of any known food source, they can be considered a universal cure, able to both delay aging and treat these diseases.
The main antioxidant agent in blueberries is anthocyanin, the pigment that gives the berries their color. In addition, the fruits contain a massive quantity of vitamin C, another powerful antioxidant with multiple benefits. Studies have shown that constant consumption of blueberries can stop signs of aging like skin spots, wrinkles, hair loss, osteoporosis or cataract, as well as all of the most severe neural and degenerative diseases.
Blueberries can help neural problems in several ways, which makes them probably the best fruit in the world for brain-related issues. Not only it protects the brain from the action of free radicals, it can also boost the transmission and intensity of neuron signals. This is very important in the fight against incurable conditions like Alzheimer’s disease or dementia. All brain functions, especially memory, can be improved by a diet rich in blueberries.
Besides anthocyanin, the most important beneficial compounds found in large amounts in blueberries are vitamin C and the essential mineral manganese. Vitamin C has numerous benefits, including firing up the immune system and faster healing of wounds.
It also speeds up growth and the regeneration of cells and tissues in general. Manganese is a critical mineral because it allows the body to assimilate essential nutrients like carbohydrates and protein, as well as eliminate cholesterol.
Another interesting and useful compound provided by blueberries is chlorogenic acid. According to studies, it has a role in regulation of glucose levels in the blood, reducing the overall quantity of sugar, which makes it extremely useful in the treatment of type II diabetes mellitus condition.
The human body is producing a very strong antioxidant named SOD, or the super oxide dismutase. In order to produce SOD, the body needs several compounds, most of which can be provided by blueberries. SOD counters the most dangerous free radicals that target the bones.
These free radicals attack and destroy the synovial fluid, which acts like some kind of oil lubricating all our joints. Thus, eating blueberries can restore the lubrication and significantly reduce the pain of arthritis.
Blueberries are also rich in flavonoids. These essential compounds protect and shelter the brain areas responsible for memory, thus reducing the memory issues that come with aging. One of the flavonoids isolated from blueberries is kaempferol, which might be able to slow down Alzheimer’s disease or even prevent it, since it shields brain tissue from external threats.
Like many other fruits, blueberries are a great source of fibers. In particular, a soluble fiber named pectin can be found in generous amounts. It acts by stopping the walls of arteries from becoming too thick, being one of the best fibers for the circulatory system. Many heart diseases are caused by narrow arteries, an effect of thick walls and plaque deposits. In time, this changes blood pressure and puts the heart under considerable stress.
Blueberries are also beneficial for hearth health due to a separate mechanism. Eating these fruits is known to reduce the cholesterol levels in the blood, not only helping the heart but providing an overall health benefit. This is because the powerful combination of fibre and antioxidants, a natural and healthy alternative to a chemical food supplement.
A secondary effect of fibers is weight control, because they give a sensation of fullness and prevent unwanted meals and snacks.
Studies have actually found evidence that blueberries might be as effective as the best prescription drugs in decreasing the levels of cholesterol. This is crucial for heart diseases, since it offers a natural way to get rid of the problem, without the severe side effects of the normal drugs.
Manganese is a bioactive mineral, which the body only needs in tiny quantities. However, even these low amounts are not easy to find, since it’s a rare element and there aren’t that many natural sources for it. Blueberries are very rich in manganese, which is critical especially for children due to its role in bone development. It is needed at any age for bone maintenance, in particular when fractures happen.
These berries are excellent for immunity because they provide the entire package of antioxidants and essential minerals that have a boosting effect on it. These include vitamins (A, B complex, C and E), as well as the antioxidant anthocyanin and bioactive minerals like selenium, zinc, copper and iron. A strong immune system allows the human body to fight against bacteria and viruses.
Other benefits of eating blueberries have been discovered by targeted modern research. A fresh study of the Rutgers Blueberry Cranberry Research Center in Chatsworth, NJ has revealed that certain compounds found in blueberries can prevent and even cure infections of the urinary tract, an effect previously studied in cranberries.
Blueberries are known to be useful in fighting cancer. Several separate compounds are responsible for this. Pterostilbene and ellagic acid provide general anti-cancer effects and help in curing this lethal disease. At the same time, cancer cell proliferation in colon cancer is stopped by the phenolic substances in blueberries.
The most potent tool against cancer in these fruits is anthocyanin. This antioxidant neutralizes the free radicals believed to be responsible for most forms of cancer, as well as aging-related conditions.
The berries are also very rich in vitamin A, which has a critical contribution to a healthy and accurate eyesight. A good supply of this vitamin can even improve and restore damaged vision.
Blueberries also contain some B-complex vitamins like folates, pantothenic acid, niacin and pyridoxine. These have a role in the processing of all three main types of nutrients: fats, proteins and carbohydrates.
In addition, blueberries are rich in numerous essential minerals, being a natural diet supplement. These include metals like manganese, copper, iron, zinc and potassium. Manganese is a building block for very strong antioxidant enzymes. Copper and iron are required in the production of red blood cells, which carry oxygen to all parts of the body.
Potassium is part of numerous tissues and fluids, with a particularly important role in the health of the heart. Overall, this cocktail of minerals also provides a morale boost and is able to fight depression and lift the mood without any additional treatment.
Habitat and cultivation
A possible side effect of eating blueberries is a severe allergic reaction that can rarely happen to some sensitive people. It is believed that the allergy is sometimes caused by the reaction to other fruits (in particular strawberries), or the more common allergies to pollen or wild weeds.
The symptoms can be skin rash, headache, wet nose, redness of mouth, swelling of the tongue or the lips, itchy eyes, wheezing or severe digestive problems. It is advised that people who are allergic to other fruits to consume blueberries with caution.