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Phytochemicals: Disease Preventatives

by Aubree E. Scott


The Media –


            According to The Phytochemical Collection, phytochemicals are biochemicals that naturally occur in plants, giving them color, smell and texture and are thought to prevent many diseases.  It has been found that phytochemicals aid in the prevention and/or treatment of cancer, diabetes, cardiovascular disease, and hypertension, which are today’s leading causes of death in the United States (Phytochemicals – Vitamins of the Future?).  Phytochemicals have also been found to have effects that are helpful to normal body function including: antioxidant effects, modulation of detoxification enzymes, stimulation of the immune system, modulation of hormone metabolism, and antibacterial and antiviral effects (Phytochemicals by Dole).  The same site adds to the list of diseases that possibly be prevented by phytochemicals with stroke, cataracts, osteoporosis, and urinary tract infections, as well as the possibility that they may slow the aging process. 

            All of these potential benefits of phytochemicals have lead people to desire the ability to a daily dose of phytochemicals in a daily supplement.  And according to Phytochemicals by Jimenez manufacturers have developed processing techniques that allow them to soften, dehydrate, and flash-freeze dry raw fruits and vegetables.  Using these techniques protects the phytochemicals, vitamins, minerals, and enzymes contained within the whole foods.  While some of these compounds maybe be able to be preserved by these techniques, Phytochemicals – Vitamins of the Future? states that supplements may only provide us with selected phytochemicals rather than the diverse array that is available when we consume the real thing. 

             How do phytochemicals help prevent or even treat these common diseases?  Many phytochemicals are natural antioxidants, protecting your body from free radical damage (Phytochemicals by Jimenez).  These antioxidants also reduce the oxidation of LDL (low-density lipoprotein) cholesterol therefore aiding in the reduction of atherosclerosis.  Reduction in the buildup of fat in the arteries may be linked to the reduction in risk of cardiovascular disease (American Heart Association).  According to Life Extension phytochemicals have estrogenic activity meaning that they are able to block normal estrogen activity by occupying estrogen receptors on breast cell surfaces, lowering the risk of breast cancer. 

            Much of the information presented in these pages has been submitted by universities and well known agencies.  This makes much of the information very reliable and much of it references the research that has already been done on phytochemicals which I will now summarize.


The Research –

            In a paper written by Mark J. Messina in The American Journal of Clinical Nutrition the phytochemical affects of soybeans, specifically the phytochemicals isoflavones.  Although the data were insufficient to conclude the protective effects of soybeans, soybean phytochemicals do demonstrate anticarcinogenic effects.  The results of the study found that there was little support for the association of soy and decreased risk of postmenopausal breast cancer, although there was limited data to support an association with decreased risk of premenopausal breast cancer.  The paper also suggests that isoflavones could play a role in protecting from osteoporosis and could be a preventative of prostate cancer.

            The antioxidant activities of grains has been studied by Adom and Liu.  In a paper titled “Antioxidant Activity of Grains” published in the Journal of Agricultural and Food Chemistry, Adom et al discussed the protective roles of whole grain consumption and the reduced risk of many diseases, including colorectal cancer, breast cancer, coronary heart disease, and diabetes, as well as total reduced mortality.  It is suggested that these reduced risks may suggest that some phytochemicals work to reduce the risk of hormone-related diseases.

            In a paper analyzing the health benefits of fruits and vegetables written by Rui Hai Lui submitted to The American Journal of Clinical Nutrition titled “Health benefits of fruit and vegetables are from additive and synergistic combinations of phytochemicals” significant protection for lung cancer was found in individuals whose intake of fruits and vegetables was high.  There were also significant results showing protective effects for cancers of the esophagus, oral cavity, larynx, pancreas, stomach, colorectal, and bladder cancers.  Evidence also suggests a link between phytochemicals and reduced risk of cardiovascular disease, mortality from coronary artery disease, and myocardial infarction.  Phytochemicals have also been shown to have roles in reducing blood pressure.  The study as shows that individual phytochemicals, when taken in supplement form, do not produce the same preventive effects and the health benefits that are gained from whole foods.  It has also been shown in patients with lung cancer that β-carotene supplements have no effect or can have a harmful effect.

            Not only can you find phytochemicals in fruits and vegetables, but they can also be found in chocolate according to a study done by Francene M. Steinberg, PhD, RD; Monica M. Bearden, RD; and Carl L. Keen, PhD.  Published in the Journal of The American Dietetic Association, “Cocoa and chocolate flavonoids: Implications for cardiovascular health” analyzes phytochemicals in chocolate and their antioxidant activity, including their effects on cardiovascular health.  Chocolate phytochemicals have been shown to protect LDL and liposomes from oxidation.  These phytochemicals may also have an effect on the immune system through modulating inflammatory responses or anti-inflammatory responses, depending on the phytochemical. 

            Are phytochemicals safe in large doses?  According to a study conducted by M. Emilia Juan, M. Pilar Vinardell, and Joana M. Planas states that they are.  Juan et al. found that after 28 days trans­-resveratrol caused no adverse effects nor increased mortality.  It was concluded that trans­-resveratrol has a large safety margin. 


Conclusions –

            There is much consistency between the media and the research.  Phytochemicals are natural and are in the foods we eat everyday.  They are completely safe and have no side effects when taken in whole foods.  They also have many beneficial effects in preventing diseases such as cancer and cardiovascular disease.  In conclusion, there is no reason not to be consuming our daily phytochemicals.


Works Cited


Adom, Kafui Kwami and Rhi Hai Liu. (2002) Antioxidant activity of Grains. Journal of Agricultural and Food Chemistry,       50, 6128-6187


American Heart Association. (2002). Phytochemicals and Cardiovascular Disease.

            Retrieved September 19, 2003, from


Davidson, Michael W and The Florida State University. (1995-2003). The Phytochemical Collection.

            Retrieved September 19, 2003, from


Dole Food Company, Inc. (2002) Phytochemicals: Another Good Reason to Eat 5-9 Servings of Fruits and Vegetables       Every Day!

            Retrieved September 19, 2003, from


Jimenez, Albert. (2002-2003). Phytochemicals.

            Retrieved September 19,2003, from


Juan, M. Emilia, M. Pilar Vinardell, and Joana M. Planas. (2002) The daily oral administration of high doses of trans-            resveratrol to rats for 28 days is not harmful. American Society for Nutritional Sciences, 257-260.


Life Extension. (1996). How To Prevent Breast Cancer.

            Retrieved September 19, 2003, from

Liu, Rui Hai. (2003). Health benefits of fruit and vegetables are from additive and synergistic combinations of phytochemicals.            The American Journal of Clinical Nutrition, 78 (suppl), 517S-520S

Messina, Mark J. (1999). Legumes and soybeans: overview of their nutritional profiles and health effects. The American             Journal of Clinical Nutrition, 70 (suppl), 439S-450S


Smith, Keith L. Phytochemicals – Vitamins of the Future?

            Retrieved September 19, 2003, from


Steinberg, Fracene M., PhD, RD; Monica M. Bearden, RD; and Carl L. Keen, PhD. (2003) Cocoa and chocolate             flavonoids: Implications for cardiovascular health. Journal of the American Dietetic Association, 103, 215-223.



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