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Can Blueberries Cure Cancer?

Your mom was right...fruit does make you healthier

By: Ashley Wood

September 20, 2006

 

 

My Story:

            When I was twelve years old my mother was diagnosed with breast cancer. After a mastectomy and chemotherapy she beat the disease and was cancer-free for eight and a half years. She had a recurrence of the same breast cancer that metastasized in her brain, lungs, liver, kidney and intestine. Through out her second round of treatment everything seemed to be the same to me; the same doctors, the same hospital the same chemo and the same results. One thing stuck out in my mind though as very different: there was always an abundance of blueberries in our refrigerator. Everyone knows that there are ads and studies all over the internet proving that some kind of organic compound or a certain kind of healing treatment can cure cancer; blueberries are no different. It seems logical that blueberries can help keep you healthy. From the time we are young we are told that fruits and vegetables are good for your health and keep you from getting sick, but can they keep you from getting cancer? Can they help you stop the spread of cancer cells? Can they cure cancer? My mother beat her cancer for a second time, and while I am prone to think that intense chemotherapy had something to do with it, the stack of blueberries that is still in our refrigerator make me wonder that maybe there is some truth to the myth.

 

 

 

“The Myth of Frank”

            Frank went to the doctor one day with a stomach ache. When he left he had two months to live. Frank’s body was filled with cancer cells and tumors. Frank heard that there were cancer-preventative compounds in blueberries, which he happened to love. He ate nothing but blueberries, over 100 quarts of them, and continued to do so every year. Frank lived for another thirty years and claimed that the blueberries cured his cancer (http://www.mnwelldir.org/docs/cancer1/success/frank.htm).

What Causes Cancer?

            Cancer is one of those mysteries in medicine. We know that it comes in all shapes in sizes and can affect almost any part of the body and we all know how dangerous and fatal it can be. Modern medicine has yet to identify exactly what causes cancer or a permanent treatment. However, we do know how to slow the rapidly spreading cancer cells and how cancer grows. An article from News Target explains that cancer is caused when a carcinogen (cancer-causing agent) causes DNA damage which in turn causes cell to mutate. In most cases the carcinogen is a free radical. Free radicals are chemical elements that have an unpaired electron in their outermost electron shell, making them very unstable elements. They attack cells and DNA strands causing oxidative stress and eventually mutated cells and cancer. (http://www.newstarget.com/z006993.html).

 

Are Blueberries Really that Healthy?                                                                                                                                 

            It seems impossible that a small blue fruit can have the same capacity as some of the world’s strongest known drugs, but studies have shown that blueberries are among some of the healthiest foods. They are rich in Vitamins C and E, manganese and dietary fibers, while maintaining a low calorie count.

 

Blueberries
1.00 cup
81.20 calories

Nutrient

Amount

DV
(%)

Nutrient
Density

World's Healthiest
Foods Rating

vitamin C

18.86 mg

31.4

7.0

very good

manganese

0.40 mg

20.0

4.4

very good

dietary fiber

3.92 g

15.7

3.5

very good

vitamin E

1.46 mg

7.3

1.6

good

World's Healthiest
Foods Rating

Rule

excellent

DV>=75%

OR

Density>=7.6

AND

DV>=10%

very good

DV>=50%

OR

Density>=3.4

AND

DV>=5%

good

DV>=25%

OR

Density>=1.5

AND

DV>=2.5%

 (http://www.whfoods.com/genpage.php?tname=foodspice&dbid=8)

 

            Aside from their great nutritional value, blueberries might contain cancer-fighting nutrients. The World’s Healthiest Foods claims that blueberries were ranked the highest out of 60 fruits and vegetables, as having the highest capacity to destroy free radicals. “Packed with antioxidant phytonutrients called anthocyanidins, blueberries neutralize free radical damage to the collagen matrix of cells and tissues that can lead to…cancer” (http://www.whfoods.com/genpage.php?tname=foodspice&dbid=8). They supposedly prevent the damage free radicals can cause. It is thought that because blueberries contain such strong antioxidants, they could play a role in controlling the proliferation of cancer cells and control free radicals.

 

 

What Do the People Think?     

There is no disagreement that blueberries are healthy and contain antioxidants and there has not been any contradicting evidence that blueberries can help prevent cancer. Generally, blueberries have been thought to help slow the spread of cancer cells and eliminate free radicals. While many sources agree that blueberries do contain antioxidants, there are several theories as to which compounds within the fruit are actually the antioxidants agent or agents. The World’s Healthiest Foods claims that the cancer preventing agents are anthocyanidins, pterostilbene, ellagic acid and phenolic compounds. An article from Vital Choices claims that it’s the polyphenol pigment in blueberries (caused by anthocyanins) that is the cancer-preventing agent. (http://www.imakenews.com/vitalchoiceseafood/e_article000402721.cfm?x=b4V1KpQ,b2Jwwny2,w) Yet another source, News Target, says that blueberries contain phytochemicals and flavenoids that make blueberries an antioxidant. (http://www.newstarget.com/z001505.html). Finally, the Wellness Directory of Minnesota says that blueberries contain resveratrol and ellagic acids that give them their cancer-fighting properties. (http://www.mnwelldir.org/docs/cancer1/success/frank.htm). Although many sources assert that different compounds are the antioxidant agent, they are all compounds or forms of the same four agents: anthocyanidins, ellagic acid, phenolic compounds, and reservatrol. Not a single source on blueberries denies the possibility of potential cancer cures; however, there doesn’t seem to be a consensus among sources and scholars about how blueberries prevent cancer. If cancer patients eat only blueberries, like Frank did, will they be cured? Do blueberries prevent all kinds of cancer? To find this information and verify what these sources claim, we need to look towards empirical evidence and medical studies.      

                                                                                                                                                                                                                                               

The Proof

            The amount of information available on this “miracle fruit” is abundant and all seem to point towards the same conclusions; that there are a number of antioxidants in blueberries and that they do in fact help prevent cancer as well as reduce the number of free radicals. According to Zheng and Wang’s (2003) study, blueberries have one of the highest levels of antioxidant activity which helps neutralize free radicals. Dunlap, Reynolds and Duffy (2006) performed a study in which they looked at how blueberries help eliminate oxidants in sled dogs. They said that exercise can contribute to oxidative stress which in turn can increase the number of free radicals in one’s body. To explore this concept they used Alaskan sled dogs and supplemented their daily diet with blueberries to see if exercised induced oxidation could be prevented. The dogs were divided into three groups; a control group, a running group (which did not receive blueberries) and a blueberry group (whose diet was supplemented with blueberries). The results showed that the dogs who did receive the blueberry supplemented diets had much higher antioxidant content in their blood. Dunlap, Reynolds and Duffy (2006) concluded that blueberries do actually increase antioxidant levels.

            This may work for dogs, but what about humans? Do the same rules apply? Schmidt, Erdman ad Lila (2005) looked at the polyphenolic compounds in blueberries and the effect they might have on prostate cancer cell lines. They looked at the compound proanthocyanidin and examined how this inhibited the growth of two different prostate cancer cell lines. They found that certain proportions of proanthocyanidin had an effect on some androgen-dependent cancel cell lines and even inhibited cell growth to 11% of the experimental control. Schmidt, Erdman and Lila showed that blueberries can effect cancer growth, but only in specific cases with specific cancer cell lines. After the study Dr. Lila reported that “the results were very positive, adding evidence to a growing body of work coming out of our lab investigating Wild Blueberry fractions and their cancer-fighting properties at all stages: initiation, promotion and proliferation. Wild Blueberry compounds offer a multi-pronged attack against cancer” (http://www.imakenews.com/vitalchoiceseafood/e_article000402721.cfm?x=b4V1KpQ,b2Jwwny2,w). Yi, Fischer, Krewer and Akoh (2005) went further with Lila’s idea and tested the effects of blueberries on colon cancer. They looked at phenolic acids, tannins, flavonols and anthocyanins in blueberries and assessed how these compounds prevent the spread of colon cancer cells. Their results showed that flavonol and tannin fractions reduced the spread of cancer cells by 50% and that phenolic acids were slightly less successful, but still prevented the growth of the cancer cells. Of all four compounds, anthocyanin fractions produced the best result by preventing the spread of cancer cells by over 50% using low concentrations of the compound. Ultimately the study concluded that there are several compounds found in blueberries that do prevent the spread of colon cancer cells. Yi, Fisher, Krewer and Akoh (2006) conducted another study the next year under the same premises and techniques and found that blueberries prevent the spread of liver cancer cells as well. This suggests that blueberries may prevent the spread of almost all kinds of cancer.

Do Blueberries cure cancer?

            We have seen from multiple studies that the compounds in blueberries can prevent the spread of cancer cells, but can these same compounds actually cure cancer? Could there be some truth to Frank’s story? In order for cancer cells to be destroyed, cell death, called apoptosis, needs to occur. Yi, Fisher, Krewer and Akoh (2005) explain that in a healthy body, cell growth and cell apoptosis (death) can occur and very similar rates and balance each other out. However, when a tumor develops, cell growth happens more than cell apoptosis which helps promote the growth of cancer cells. They claim that even small changes in this balance by promoting cell apoptosis can help maintain a healthy balance and can decrease the progression of cancer cells. Therefore, to help cure cancer, you need cell apoptosis to put the balance of cell growth and death back in balance. Yi, Akoh, Fischer and Krewer (2006) looked at the compound in blueberries and how it affects cell apoptosis. Their study showed that anthocyanin can actually increase DNA fragmentation by two to four times the normal amount which results in the induction of cell apoptosis. Essentially Yi, Akoh, Fischer and Krewer (2006) found that anthocyanin compounds in blueberries not only prevent the spread of cancer cells like the other three compounds, but they actually increase the amount of cancer cell death.

 

 

 

 

 

 

 

Conclusion         

            There seems to be a comprehensive agreement among varying sources that blueberries prevent the growth of cancer cells. The National Cancer Institute has even said that research has shown that the compounds in blueberries help protect against cancer (Wedge et al, 2001). This is not to say that if you eat blueberries every day you will be safe from cancer, but it does show that there are some natural compounds that can help protect you. Blueberries can help prevent the initiation of cancer by destroying free radicals, the proliferation of cancer by controlling the growth of cancer cells and the reduction of cancer cells through cell apoptosis. With more research and understanding cancer preventative measures we will be able to see just how much truth there is in Frank’s story and maybe one day will be able to prevent cancer all together with natural compounds and a healthy diet. Essentially, your mother was right…eat your fruits and vegetables, they can make you healthy.

 

 

References and More Information:                                                                                                                  

 

 

(1) Weatherby, Craig. “Blueberries Found to Fight Cancer and Infection.” 19 May, 2005.  http://www.imakenews.com/vitalchoiceseafood/e_article000402721.cfm?x=b4V1KpQ,b2Jwwny2,w

 

(2) “Blueberries, cranberries, strawberries all contain powerful phytochemicals that fight cancer, heart disease, high cholesterol and more” 26 July, 2004.  http://www.newstarget.com/z001505.html

 

(3) “Frank’s Story” Wellness Directory of Minnesota, 2001. http://www.mnwelldir.org/docs/cancer1/success/frank.htm

 

(4) The World’s Healthiest Foods http://www.whfoods.com/genpage.php?tname=foodspice&dbid=8

 

(5) Dunlap, Kriya L., Reynolds, Arleigh J., and Duffy, Lawrence K. (2006). Total antioxidant power in sled dogs supplemented with blueberries and the comparison of blood parameters associated with exercise. Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology, 143 (4): 429-434.

 

(6) Schmidt, Barabra M., Erdman, John W. Jr., Lila, Mary Ann (2005). Differential effects of blueberry proanthocyanidins on androgen sensitive and insensitive human prostate cancer cell lines. Cancer Letters.  231 (2): 240-246

 

(7) Wedge, D.E., Meepagala, K.M., Magee, J.B., Smith, S.H., Huang, G., and Larcom, L.L. (2001). Anticarcinogenic activity of strawberry, blueberry, and raspberry extracts to break and cervical cancer cells. Journal of Medical Foods. 4: 49-51.

 

(8) Yi, W., Fischer, J., Krewer, G., and Akoh, Casmir C. (2005). Phenolic Compounds from Blueberries Can Inhibit Colon Cancer Cell Proliferation and Induce Apoptosis. Journal of Agricultural and Food Chemistry. 53 (18): 7320-7329.

 

(9) Yi, W., Akoh, Casimir C., Fischer, J., and Krewer, G. (2006). Effects of phenolic compounds in blueberries and muscadine grapes on HepG2 cell viability and apoptosis. Food Research International. 39 (5): 628-638

 

(10) Zheng, W. and Wang S.Y. (2003). Oxygen radical absorbing capacity of phenolics in blueberries, cranberries, chokeberries, and lingonberries. Journal of Agricultural and Food Chemistry. 51: 502-509

 

 

 

 

 

 

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