Research has determined that some 20 to 50 percent of total cancers are influenced by diet. Dietary fat, meat, alcohol, excess calories, and low intakes of fruits and vegetables are the focus of ongoing research on cancer occurrence. Diet relates to cancer in several ways foods or their components may cause cancer, or promote cancer, or protect against cancer. This issue of Nutrition Spotlight looks at the links between our diets and cancer specifically, cancers of the prostate, breast and colon, as well as oral cancers. Additionally, we look "inside" K-State's Terry C. Johnson Center for Basic Cancer Research, and we share the healthful benefits of whole grains through information and a recipe.
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How does diet fight off cancer? Studies of populations suggest that low rates of many, but not all, kinds of cancer correlate with intakes of fiber-rich fruit, vegetables, and whole grains, particularly whole wheat. The mechanism for the protection is not clear, but one popular theory is that the fiber in fruit and vegetables helps to protect against some cancers by speeding up the transit time of all materials through the colon, decreasing the time that colon walls are exposed to cancer-causing substances.
Folate deficiency seems to make cancers of the cervix and colon more likely. One theory supporting this belief estimates that 10% of the US population, and a much higher percentage of persons with low incomes, eat a diet low enough in folate to cause breaks in DNA that make cancer development more likely. Some anticarcinogens, especially some phytochemicals, may protect agains cancer by acting as mild toxins that force the body to strengthen its supply of carcinogen-destroying enzymes. Vitamins A, B6, B12 and pantothenic acid may oppose cancer in other ways. Vitamins E, C and beta-carotene are known for their antioxidant roles and cancer-fighting effects. Functional foods, containing phytochemicals believed to promote health, are by definition "potentially healthful products that may provide a health benefit beyond the traditional nutrients it contains." Examples of functional foods are the tomato products discussed on page 3 that are high in the phytochemical lycopene.
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Recent research adds to our support of increased servings of colorful fruits and vegetables in the diet. In November 2006, researchers from UCLA reported that the phenolic content of a wide range of berries, including blueberries, strawberries and raspberries, could inhibit cell growth and spread for a wide range of cancers. Their study, a lab study, holds promise for human health.
In a study to appear in the January 2007 issue of The Federation of American Societies for Experimental Biology, researchers from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans. Although phenols, the known antioxidant compounds found also in dark chocolate, red wine, tea and fruits and vegetables, are high in olive oil, they were not the only compounds in olive oil that reduced oxidative damage to cells.
Spotlight on K-State's Terry C. Johnson Center for Basic Cancer Research: An interview with Marcia Locke, Public Relations and Outreach Coordinator
It started small and in a basement. But after 26 years of growth, the Terry C. Johnson Center for Basic Cancer Research now supports cancer-related research with more than 50 scientists across Kansas State University while providing educational opportunities and outreach. Its administrative offices are now located in spacious Chalmers Hall, constructed in 2002.
The late Dr. Terry C. Johnson, a K-State distinguished professor of biology, founded the non-profit Center for Basic Cancer Research in 1980. The Center augments cancer-related research of K-State faculty across disciplines with funds for both new and on-going projects.
Four of the Center's affiliated scientists are faculty in the Department of Human Nutrition and have been featured in Nutrition Spotlight interviews previously, including:
• George Wang, at www.oznet.ksu.edu/humannutrition/spotlight/JunJul.pdf ;
• Denis Medeiros, at www.oznet.ksu.edu/humannutrition/spotlight/Janfeb02.pdf ;
• Mark Haub, at www.oznet.ksu.edu/humannutrition/spotlight/marapril01.pdf ;
• Rick Baybutt, at www.oznet.ksu.edu/humannutrition/spotlight/novdec00.pdf
The Center also offers travel money for faculty training to learn new research techniques, and encourages networking among the faculty. A simple application process is completed by those K-State scientists who are interested in receiving Center funds.
In addition to fostering cancer-related research among faculty, the Center encourages K-State undergraduates and graduate students to conduct cancer-related research. The Center provides 50 undergraduate student cancer research awards per year to students and their faculty mentors. Each interested student applies for the monetary award through a faculty mentor.
Outreach is another aspect of the Center's programming efforts. At times, the Center's staff speaks about cancer prevention behaviors and cancer research to local cancer survivor groups, the public and to philanthropic organizations. The staff also collaborates with other agencies in community events that help raise awareness of cancer and help enact legislative policies that target cancer incidence. Additionally, the Center produces cancer-related educational brochures, such as "When a friend has cancer..."
One of the Center's largest cancer educational outreach projects is a picture book to help young children understand cancer. Written for children seven to ten years of age, the story (A Day with Dr. Waddle) can help people of all ages understand what cancer and research are, and how they can practice healthy habits. Reading the book can also be a "safe" way to begin discussing a difficult topic with children with a family member or friend who has been diagnosed with cancer.
The activity book, which has pictures to color and word puzzles to solve, is available for $2.00, with a 20% discount offered for orders of 50 or more books. It can be ordered in both English and Spanish from the Center, telephone number 785-532-6705. If a county Extension agent wishes to distribute the books "en masse" to each second grade school child in his or her community, call Marcia Locke at the Center for information about help to fund your project.
The Center funds all of its programs through private donations. For information on making a gift, call Sheila Walker at the K-State Foundation, phone number 1-800-432-1578.
For more information about K-State's Terry C. Johnson Center for Basic Cancer Research, visit the website www.k-state.edu/cancer.center (MH)
Most people have heard messages promoting the health benefits associated with fruits and vegetables as part of a healthy and balanced diet. Many studies have indicated that adequate consumption of fruits and vegetables may decrease the risk of some cancers, such as prostate cancer. So, what exactly is in fruits and vegetables that allow them to have a protective role against some cancers? Vitamins? Minerals? Antioxidants? Phytochemicals?
Lycopene, a phytochemical naturally found in several fruits and vegetables, may lower the risk of prostate cancer in men. Lycopene is the substance responsible for giving some fruits and vegetables such as tomatoes, watermelon, pink grapefruit, and guava their red color. Lycopene serves as an antioxidant in the body by preventing or repairing cell damage and it seems to be able to slow down cancer cell growth.
Although lycopene is found in most red colored fruits and vegetables, tomatoes and tomato products are the most abundant sources. Lycopene concentration varies between the variety (cherry, grape, plum, Italian.) and ripeness (green, yellow, orange, red) of tomatoes and the brand of tomato products.
Research has shown that lycopene can be better absorbed and utilized by the body after it has been processed in food products such as sauces, pastes, juices, or ketchup. In fresh fruits and vegetables, lycopene is found within the fruit or vegetable tissue, thus decreasing its availability. Processing forces the fruit or vegetable tissue to release the enclosed lycopene; therefore, the amount available for absorption increases. Here is a chart that details the milligrams of lycopene available in one cup of certain tomato products:
| Product | Lycopene |
| 1 cup chopped fresh tomatoes | 4 mg |
| 1 cup canned tomatoes | 10 mg |
| 1 cup of tomato juice | 22 mg |
| 1 cup of tomato sauce | 37 mg |
| 1 cup of ketchup | 40 mg |
| 1 cup of tomato paste | 76 mg |
The more processing the tomato undergoes, the higher the lycopene concentration. Also, lycopene is fat soluble, so adding a little oil to the diet will improve its absorption by the body.
To decrease the risk of prostate cancer, men are encouraged to consume lycopene-rich foods. Eating a variety of fruits and vegetables, as part of an overall healthy diet, is a good way to get those lycopene-rich foods into the diet. Although lycopene has been shown to protect against prostate cancer, researchers are still investigating how this nutrient is able to perform such an important role. (TK)
Breast Cancer affects over 212,930 men and women a year and is second only to skin cancer in frequency. Women are more highly susceptible to this form of cancer in part because of the production of estrogen. Higher levels of estrogen in the bloodstream are linked to the growth of cancer cells. Since many overweight women have higher estrogen production it is important for women to eat a healthful diet and be physically active in order to achieve and maintain a healthy weight.
There is conflicting information about the role of diet in combating breast cancer. For years a low fat diet rich in fruits, vegetables, and grains was touted as effective in reducing the incidence of this type of cancer. The Women's Health Initiative Study, a study that followed 49,000 participants over an eight year period, found that breast cancer was not reduced by the restriction of overall (total) fat in the diet. A major limitation in this study was that overall (total) fat in the diet was lowered rather than targeting specifically saturated fats. This meant that both polyunsaturated as well as unsaturated fats were also constricted. Trans fats were also not specifically addressed in the study because, at the time, there was limited knowledge of their effects on the body. However, the study did show that there was a reduced incidence of breast cancer in those women who decreased their saturated and trans fat intake and were more diligent about increasing their fruit and vegetable consumption.
A recently released study by Harvard Medical School, also known as the Nurse's Health Study II, shows that there is also a link between red meat intake and breast cancer. This study tracked dietary intake from 1989 to 2003 and found that those women who consumed one and a half servings or more of red meat a day doubled their chances of developing hormone receptor-positive breast cancer. Explanations for this include the development of cancer causing chemicals during cooking or processing, growth hormones used in cattle production, and the abundance of heme-iron in red meat. The study also stated that further investigation must be conducted and discussed the difficulty of identifying specific cancer causing foods given the variety in the American diet.
So, what is a person to do? The Cancer Research and Prevention Foundation instructs that consumers maintain a healthy weight, eat a low-fat diet rich in fruits and vegetables, consume whole grains, and exercise. The maintenance of healthy weight is even more important after menopause. Physical activity can assist in maintenance of a healthy weight as well as boost the immune system. Limiting alcohol consumption is also advised because of its increased association with breast cancer-- especially for those already at high risk. Dietary modification and physical activity coupled with self breast exam and annual mammograms can be effective in eliminating or reducing the incidence of breast cancer. For a comprehensive and informative fact sheet go to http://www.preventcancer.org/healthyliving/cancerinfo/breast.cfm (TB)
Oral cancer affects the lips, tongue, cheek, mouth, sinuses or throat. Approximately 75% of all cases of oral cancer are caused by excessive tobacco and alcohol use. These substances damage healthy cells in the lining of the mouth and throat. Cells then grow faster than normal in order to repair the damage. Alcohol and tobacco are a particularly bad combination. Alcohol increases the ability of DNA-damaging chemicals present in tobacco to penetrate deep into the cells of the mouth and throat. As a result, abnormal cells can accumulate and form tumors.
There are several things an individual can do minimize the risk factors for oral cancer. The obvious action is to avoid tobacco and limit alcohol consumption. It is also a good idea to consume a varied diet that includes a generous amount of fruits and vegetables as well as limit the amount of red meats—especially the ones with higher fats or those that are processed. In addition, it is also important to wear lip protection with SPF when out in the sun.
Scientists are finding that fruits and vegetables with deep color seem to be important in the prevention of many kinds of cancers. One chemical that may provide a protective quality is anthocyanin. Colorful black raspberries offer particular interest as they seem to have the ability to slow the growth of oral cancer cells. Researchers at The Ohio State University School of Public Health exposed hamsters to a cancer-causing chemical and then fed them an extract of black raspberries mixed into their food. The hamsters loved the berry flavor! Not only did the hamsters relish the berries, they experienced a 50% reduction in incidence of oral tumors. Scientists then tried the berry extract on human oral cancer cells in the laboratory. As a result, there is hope that in the future a lozenge or gel made of the extract of this fruit could be available for use by cancer patients.
In other institutions, research is being conducted on the efficacy of green tea in promoting oral health. Preliminarily, it appears it may be important for anticancer chemicals present in green tea (polyphenols) to have frequent contact with oral tissue for best results. Interestingly, the Chinese who have a much lower rate of oral cancer often sip green tea throughout the day. Much work still needs to be done in this area before green tea can be recommended for oral health.
According to Cynthia Stein of the Harvard Center for Cancer Prevention at Harvard Medical School, there is mounting evidence that eating a generous amount of a variety of colorful fruits and vegetables can lower the risk of oral cancer. Now we know that summer berries are not only mouthwatering but also are mouth-healthy! (KH)
The majority of the research on diet and cancer suggests that eating fruit, vegetables, whole grains and beans will lower your risk of developing cancer. Here is a list of foods that the American Institute of Cancer recommends as cancer fighters:
No single food or food substances can protect you against cancer, but the right combination of foods a predominantly plant-based diet can. That is why scientists recommend that at least 2/3 of your plate should be filled with vegetables, fruit, whole grains and beans.
Why a certain person gets a disease, such as cancer, and another does not remains a mystery. While genetics play a major role, studies of the patterns of cancer development in the U.S. population teach us that dietary habits influence an individual's chance of developing cancer.
Cancer in the lower end of the digestive system, in the colon or rectum, or both, is the third most common type of cancer in the world. About three out of four cases of colorectal cancer occur in people without a family or personal history of the disease.
According to the National Cancer Institute, which is part of the National Institutes of Health, cancers of the colon and rectum are the second leading cause of cancer death in the U.S., with more than 55,000 people dying from this type of cancer each year.
One out of three deaths from colorectal cancer could be avoided if every person got a simple screening test regularly. Screening tests are given to look for cancer before a person has any symptoms. Screening checkups help find cancer early, when it is usually easier to treat.
If you are age 50 years and older, ask your health care provider about getting a colorectal health check-up each year.
More research is needed as to whether a diet high in fiber, fruits and vegetables, and low in fat, decreases the risk of colorectal cancer. Some studies have shown that this type of diet helps protect against colorectal cancer. Other studies, however, have shown no effect on preventing colorectal cancer from this type of diet.
For overall health, current dietary guidelines include:
For more information about cancer, visit the
website, www.cancer.gov
Cooking most grains is similar to cooking rice. You put the dry grain in a pan with water or broth, bring to a boil, then simmer until the liquid is absorbed. Pasta and grano are generally cooked in a larger amount of water; the excess is drained away after cooking. Don't be intimidated! The chart in the next column provides some guidelines to follow. (KW)
Here's a healthy, homemade recipe for granola that is low-fat and the perfect start to making half your grains whole! Try it as a healthy cold cereal with milk or as a great topping to sprinkle on yogurt, ice cream, pudding, custard or fruit!
Granola Cereal
Makes 5 1/2 cups
Nutritional analysis: One serving (1/4 cup) provides approximately 110 calories, 3 g protein, 19 g carbohydrates, 3 g fat (1 g saturated), 0 mg cholesterol, 4 g fiber, 15 mcg folate, 1 mg iron, 5 mg sodium (KW)
What is a "whole grain?" Whole grains contain the entire grain kernel the bran, germ and the endosperm each containing specific nutrients. Grain products are generally low in fat, rich in fiber, complex carbohydrates, plant protein, phytochemicals, antioxidants, B vitamins and minerals (iron, magnesium and selenium). Some examples of whole grains are: whole wheat flour, bulgur, oatmeal, popcorn, whole cornmeal, brown rice, barley and wild rice.
Don't be misled, however. Foods that claim to be "multi-grain", "100 percent wheat" or "high fiber" are not necessarily whole grain. Look for the word "whole" before the first or second ingredient.
Whole grain foods, as part of a healthy diet, can help you stay healthy. They may reduce the risk of heart disease or diabetes and increasing whole grain may help reduce the risk for certain cancers, especially cancers of the stomach and colon.
If you're not getting whole grains in your diet, try a snack mix made with a variety of whole
grains, choose a whole grain muffin or bread, prepare brown rice or substitute whole white wheat flour for 1/2
the white flour in cookies. White, whole wheat flour is light-colored and mild-tasting. For your good
health's sake, eat at least 3 ounces of whole grains every day. (KW)
Questions or concerns about this publication? Contact Shelly Burklund, 207 Justin Hall, Manhattan, KS 66506, Phone: (785) 532-1670, FAX: (785) 532-1678