Blueberries are not only popular, but also repeatedly ranked in the U.S. diet as having one of the highest antioxidant capacities among all fruits, vegetables, spices and seasonings. Antioxidants are essential to optimizing health by helping to combat the free radicals that can damage cellular structures as well as DNA. We recommend enjoying raw blueberries — rather than relying upon blueberries incorporated into baked desserts — because, like other fruits, raw blueberries provide you with the best flavor and the greatest nutritional benefits.
As one of the few fruits native to North America, blueberries have been enjoyed by Native Americans for hundreds of years. They have also enjoyed great popularity around the world in cuisines from Asia to the Mediterranean.
In the popular press, blueberries have reached superstar status in terms of their unique health benefits. While we prefer to think of all the World's Healthiest Foods as rightful superstars, we can understand many of the special accolades being given to this wonderful berry. Most health research on blueberries involves their phytonutrient content. Anthocyanins - the colorful antioxidant pigments that give many foods their wonderful shades of blue, purple, and red - are usually the first phytonutrients to be mentioned in descriptions of blueberries and their amazing health-supportive properties. The benefits are:
Maintaining healthy bones
The iron, phosphorous, calcium, magnesium, manganese, zinc and vitamin K in blueberries all contribute to building and maintaining bone structure and strength.
Iron and zinc play crucial roles in maintaining the strength and elasticity of bones and joints.2 Low intakes of vitamin K have been associated with a higher risk for bone fracture, while adequate vitamin K intakes improve calcium absorption and may reduce calcium loss.5
Lowering blood pressure
Maintaining a low sodium intake is essential to lowering blood pressure. Blueberries are naturally free of sodium and contain potassium, calcium, and magnesium, all of which have been found to decrease blood pressure naturally.3
Studies have shown that type 1 diabetics who consume high-fiber diets have lower blood glucose levels and type 2 diabetics may have improved blood sugar, lipids and insulin levels. One cup of blueberries contributes 3.6 grams of fiber.
The Dietary Guidelines for Americans recommends 21-25 grams of fiber per day for women and 30-38 grams per day for men.
Warding off heart disease
The blueberry's fiber, potassium, folate, vitamin C, vitamin B6 and phytonutrient content, coupled with its lack of cholesterol, all support heart health. The fiber in blueberries helps lower the total amount of cholesterol in the blood and decrease the risk of heart disease.
Vitamin B6 and folate prevent the buildup of a compound known as homocysteine. When excessive amounts of homocysteine accumulate in the body, it can damage blood vessels and lead to heart problems.
Vitamin C, vitamin A, and various phytonutrients in blueberries function as powerful antioxidants that help protect cells against free radical damage. They inhibit tumor growth, decrease inflammation in the body and help ward off or slow several types of cancer, including esophageal, lung, mouth, pharynx, endometrial, pancreatic, prostate and colon.1
Blueberries also contain folate, which plays a role in DNA synthesis and repair, thus preventing the formation of cancer cells from mutations in the DNA.1
Improving mental health
Population-based studies have shown that consumption of blueberries can reduce the risk of cognitive decline as well as Parkinson's disease - a neurodegenerative disorder resulting from cell death in parts of the brain.5
Studies have also revealed that in addition to reducing the risk of cognitive damage, blueberries can also improve short-term memory loss and motor coordination.4
Because of their fiber content, blueberries help to prevent constipation and promote regularity for a healthy digestive tract.
Weight loss and satiety
Dietary fiber is commonly recognized as an important factor in weight loss and weight management by functioning as a "bulking agent" in the digestive system. High fiber foods increase satiety and reduce appetite, making you feel fuller for longer and thereby lowering your overall calorie intake.
Collagen, the skin's support system, relies on vitamin C as an essential nutrient that works in our bodies as an antioxidant to help prevent damage caused by the sun, pollution and smoke. Vitamin C also promotes collagen's ability to smooth wrinkles and improve overall skin texture. Just one cup of blueberries provides 24% of your daily need for vitamin C.
Blueberries are phytonutrient superstars. These fruits contain significant amounts of anthocyanadins, antioxidant compounds that give blue, purple and red colors to fruits and vegetables. Included in blueberry anthocyanins are malvidins, delphinidins, pelargonidins, cyanidins, and peonidins. In addition to their anthocyanins, blueberrries also contain hydroxycinnamic acids (including caffeic, ferulic, and coumaric acid), hydroxybenzoic acids (including gallic and procatechuic acid), and flavonols (including kaempferol, quercetin and myricetin). Blueberries also contain the unique, phenol-like antioxidants pterostilbene and resveratrol.
Blueberries are a very good source of vitamin K, vitamin C, and manganese. Blueberries are also a good source of fiber and copper.
( Some of the info from this article is taken from http://www.medicalnewstoday.com/ )