Blueberry Health Benefits

From research labs all across the country and the world, there is growing evidence that blueberries could be powerful little disease fighters. Here is a summary of what we have learned so far.

Antioxidants - Researchers at the USDA Human Nutrition Center (HNRCA) have found that blueberries rank #1 in antioxidant activity when compared to 40 other fresh fruits and vegetables. Antioxidants help neutralize harmful by-products of metabolism called "free radicals" that can lead to cancer and other age related diseases. Anthocyanin -- the pigment that makes the blueberries blue -- is thought to be responsible for this major health benefit. (reference) More on antioxidants: (antioxidants)

Anti-Aging - In another USDA Human Nutrition Center (HNRCA) lab, neuroscientists discovered that feeding blueberries to laboratory rats slowed age-related loss in their mental capacity, a finding that has important implications for humans. Again, the high antioxidant activity of blueberries probably played a role. (reference)

Disease Prevention - Blueberries may reduce the build up of so called "bad" cholesterol that contributes to cardiovascular disease and stroke, according to scientists at the University of California at Davis. Antioxidants are believed to be the active component. (reference)

Prevention of Urinary Tract Infections - Researchers at Rutgers University in New Jersey have identified a compound in blueberries that promotes urinary tract health and reduces the risk of infection. It appears to work by preventing bacteria from adhering to the cells that line the walls of the urinary tract. (reference)

Blueberries and Eyesight - A number of studies in Europe have documented the relationship between bilberries, the European cousin of blueberries and improved eyesight. This is thought to occur because of the anthocyanin in the blue pigment which is also available in the blueberry. One study in Japan documented that blueberries helped ease eye fatigue. (reference)

New Research

(Under Construction) Around the world, blueberries are being studied in health and medicinal studies. Here we will post details on some of the more promising studies underway.

Eating blueberries may help you remember where you placed your car keysimportant findings if youd like to keep Alzheimers and heart disease at bay.

The research was presented Monday, August 19, at the ACS national meeting in Boston.

In one study, Jim Joseph, director of the neuroscience laboratory in the USDA Human Nutrition Center (HNRCA), fed blueberry extractionsthe equivalent of a human eating one cup of blueberries a dayto mice and then ran them through a series of motor skills tests.

He found that the blueberry-fed mice performed better than their control group counterparts in motor behavioral learning and memory, and he noticed an increase in exploratory behavior. When he examined their brains, he found a marked decrease in oxidative stress in two regions of the brain and better retention of signal-transmitting neurons compared with the control mice.

The chemical that appears responsible for this neuron protection, anthocyanin also gives blueberries their color and might be the key component of the blueberrys antioxidant and anti-inflammatory properties. Blueberries, along with other colorful fruits and vegetables, test high in their ability to subdue oxygen free radicals. These oxygen radicals, which can damage cell membranes and DNA through a process known as oxidative stress, are blamed for many of the dysfunctions and diseases associated with aging.

These findings could become increasingly important as the U.S. population ages. It is projected that by 2050, more than 30% of Americans will be over 65 and will have the decreased cognitive and motor function that accompanies advanced age. Joseph is currently testing the effects of blueberries on humans. Preliminary results show that people who ate a cup of blueberries a day have performed 56% better on motor skills tests than the control group.

Ethnobotany and Blueberries

Blueberries have been associated with positive physiological and cosmetic benefits for centuries. Here we list non scientific information which although not endorsed by the USHBC, may be of interest to researchers as a direction for further research.

Blueberry Health and Nutrition traditions in China. (under construction)

Native American and First Nations of Canada blueberry health and medicinal traditions. (under construction)

Blueberry health and nutrition in Russia and Central European Traditions. (under construction)

Bibliography

Prior, RL, et. al. J of Agric. Food Chem. 1998, 46:2686-2693
Bickford, P.C. et. al. Society for Neuroscience Abs. 1998, 24: 2157
Heinenen, L.M. et al. J. Agric. Food Chem. 1998, 46:4107-4112
Howell, A.B. and V. Nicholi. New Engl. J. Med 1998, 339: 1085-1086

Nutrition Summary

The following summarizes some of the published research in the area of nutraceuticals and health.

The belief that food products have medicinal properties has been celebrated in folk medicine for centuries. Today food properties are being explored by the medical and scientific fields. Some cultures have long valued many naturally occurring substances believed to have preventative and therapeutic value. In the United States, nutraceuticals are part of a rapidly expanding area of biomedical research, generating considerable interest among consumers, manufacturers, and regulators alike. This is a progressive area; the field is continually conducting studies and discovering possible benefits.

Though blueberries themselves are not a cure-all, they contain a number of substances which are thought to have health benefits. These substances include, but are not limited to fructose, fiber, vitamins and antioxidants. Antioxidants thus far, seem to have the most conclusive role in the prevention/ delaying of such diseases as cancer, heart disease and the aging process however, a limited number of studies, especially long term and on human beings, are not available at this time.

What is a Nutraceutical?

Nutraceutical- Any substance that may be considered a food or part of a food that provides health benefits, including the prevention or treatment of disease. They range from isolated nutrients to genetically engineered "designer foods".

The term "nutraceutical" was coined by The Foundation for Innovation in Medicine in 1989 to provide a name for this area of biomedical research, and has since become part of the standard lexicon in both the medical - scientific community and in the food and drug industries (The Foundation for Innovation in Medicine, 1991). The wide acceptance of this term itself provides ample testimony that a new product category is ready to be born. Largely based on their cultural and historical beliefs, Japan and many European countries hold established places in the international marketplace for nutraceuticals. They have long valued many natural substances that hold preventative and therapeutic values, and have a rapidly expanding body of research to back them up. The United States, however, is at the beginning of this process. Nutraceuticals have become a focal point for updating the U.S. economic and regulatory system in response to worldwide medical and scientific trends.

Free Radicals - Antioxidants:

Antioxidants are thought to help protect the body against the damaging effects of free radicals and the chronic diseases associated with the aging process (Ames, 1993). Fresh fruits (blueberries) and vegetables contain many of these naturally occurring antioxidants such as vitamins A, C and E.

Blueberries contain 0.04 mg of beta-carotene, 13 mg of vitamin C and 1 mg vitamin E per 100 g of blueberries. Blueberries contain 10 RE (Retinol Equivalents, a unit of vitamin A) of vitamin A per 100 grams of blueberries. The RDA for vitamin A is 1000 RE for men and 800 RE for women. In addition, blueberries contain anthocyanins and phenolics that can also act as antioxidants.

Ellagic and Folic Acid:

Although their modes of action is still poorly understood, it appears that these acids may inhibit cancer initiation. Ellagic acid (in its most biologically active form, ellagitannin) is found in blueberries and some other berries. (Stoner, 1989).

Folic acid may help guard against cervical cancer (Toufexis, 1992), and may benefit the fetus during pregnancy. Blueberries contain 6 ug./ 100g of folic acid. The RDA for women is 180 ug.

Other Substances: Antibacterial Agents

In Sweden, dried blueberries are used to treat childhood diarrhea (Kowalchuk, 1976). This use is attributed to anthocyanosides, a natural substance found in blueberries which is believed to be "lethal" to E. Coli (a bacteria sometimes linked to the infection).

Fiber: Multiple Health Benefits

Considerable evidence collected over the last 20 years has proven the numerous advantages of high fiber diets (Potter, 1986). Blueberries are a source of dietary fibers: 2.7g/100g. A diet containing 25g. of dietary fiber per day is generally recommended.

Blueberries contain a variety of compounds. These include: antioxidants, anthocyanosides, bacterial inhibitors, folic acid, vitamins A and C, carotenoids, ellagic acid, folic acid, and dietary fibers. The significance of their presence and modes of action remain largely unexplored.

Sources:

1.      The Foundation for Innovative Medicine, The Nutraceutical Initiative: A Proposal for Economic and Regulatory Reform. December1991

2.      Kowalchuk J. Antiviral Activity of Fruit Extracts. J Food Science. 41: 1013-1017, 1976

3.      Potter N. Food Science 4th ed. Conn: A VI 1986

4.      Potter N. Do Functional Foods Raise the Health Threshold. The World of Ingredients. Oct.-Nov. 54-55, 1994

5.      Stoner G.. Ellagic acid: A Naturally Occurring Inhibitor of Chemically-Induced Cancer. 1989

6.      Toufexis A. The New Scoop on Vitamins. Time 139(14). 1992

7.      Ames BN, Shigenaga MK, Hagen TM. Oxidants antioxidants, and the degenerative diseases of aging. Proc. Natl. Acid. Sci. USA 90:7915-7922, 1993.