What's the Link Between
Food & Cancer?
by Eve Jacobs
Fruits and veggies are good. Fats and white flour are bad. Red wine is good-maybe? But heavy alcohol drinking is bad. Fish is good - despite some kinds having dangerous levels of toxins. Red meat is not a happy choice - usually.
ietary information in the news is contradictory and seems to change before we can even absorb it. So, how delightful to have the opportunity to chat with Elisa Bandera, one of the authors of the American Cancer Society’s 2006 Guidelines on Nutrition and Physical Activity for Cancer Prevention. The 42-page report, published in the September/ October 2006 issue of CA: a Cancer Journal for Clinicians, is a trifle overwhelming — too much of a good thing. Perhaps Bandera would pilot us through a condensed version of the tome?
Bandera’s pride of authorship is evident — she is more than willing to be both interpreter and guide. What do the experts agree on? Their opening paragraph is actually a stunner: Studies to date indicate that one third of cancer deaths in the U.S. are attributable to tobacco exposure and another third to diet and exercise habits. So, fully two thirds of cancers are likely preventable through lifestyle changes.
She explains: “The recommendations are basic, easy-to-follow principles and are based on scientific evidence. These include maintaining a healthy weight, staying physically active, eating a healthy diet mostly from plant sources — emphasizing a variety of fruits, vegetables and whole grain products — and if you drink, doing so in moderation. That means less than one drink each day for women and less than two drinks for men.”
Overweight and obesity are the number one problem in this country — largely responsible for 14 percent of cancer deaths in men and 20 percent in women, according to Bandera. “So, achieving a healthy weight and staying there tops the guidelines.” Several malignancies have a clear tie-in to obesity: adenocarcinoma of the esophagus and cancers of the colon, endometrium, kidney, and breast in post-menopausal women. Evidence indicates that overweight individuals may also be at higher risk for cancers of the pancreas, gallbladder, thyroid, ovary and cervix, and for multiple myeloma, Hodgkin lymphoma and aggressive prostate cancer.
Of course, overweight is a complex problem that has been analyzed from every angle under the sun. Bandera’s prescription is simple: Take in no more calories every day than what you use. Keep the portion sizes down; replace high fat, high carb, low nutrient foods with the good stuff — vegetables, fruits, whole grains, beans and nuts; and steer clear of eating out a lot because portions are too large, there are hidden fats in those tasty treats and most meals are low in the good stuff.
Bandera recommends relying on home cooking. “You know what goes into your home-cooked meals. You’re in control.”
“If you follow the dietary guidelines for cancer,” she continues, “you will generally be able to keep your weight in check.”
Of course, the other half of the equation is to move more. Bandera explains the difference between usual and intentional activity, both of which need to be stepped up by most people. For intentional activity (your exercise program), she recommends a minimum of 30 minutes daily, five days per week, with 60 minutes daily as a goal. “Some of this can be incorporated into your daily life, such as walking to the store for a paper or a few groceries. Also, you can split your exercise time — it doesn’t have to be in one session to be effective,” she says.
For “usual” activity, Bandera recommends pushing yourself to go above and beyond your daily routine: Climb the steps to your office several times a day if you can, take a far rather than near parking spot, don’t email your office neighbor — get up from your seat and walk.
For alcohol, Bandera says that just one drink a day increases the risk of certain cancers by 30 percent, and has been linked to malignancies of the larynx, liver, pharynx, esophagus, mouth, colon, rectum and breast. “But moderate wine drinking is said to be beneficial for cardiovascular health, so the current recommendation is to drink in moderation if you do drink.”
“If you do not drink,” she adds, “it does not make sense to start drinking to prevent cardiovascular disease because there are other ways of doing so.”
She thinks that most people are overly worried about genes. “Even if genes are involved, you still have some control.”
Bandera bemoans the fact that our environment works against us — no sidewalks, bicycle lanes, parks and recreational facilities in many communities; increased reliance on cars; longer workdays and the necessity for two adults to be employed, with little time or energy for cooking meals at home; school lunches high in fat and sugar; and last but certainly not least, the escalating popularity of electronic entertainment.
“The American Cancer Society guidelines for cancer prevention are similar to the recommendations issued by the American Heart Association, the American Diabetes Association, and the Dietary Guidelines for Americans,” Bandera adds. “Therefore, by avoiding smoking and following the guidelines, you can also prevent other major chronic illnesses such as heart disease and diabetes.”
The cancer prevention expert is concerned that only 12 percent of American adults follow the Cancer Society’s dietary guidelines, 24 percent eat the recommended five portions of fruits and vegetables daily, 66 percent are overweight and 30 percent are obese.
She explains that cancer prevention should not be limited to adulthood. “There is growing evidence that early childhood exposures, even in utero exposures, increase the risk of some cancers during adulthood. For instance, childhood obesity is linked to early puberty, which is a well-established risk factor for breast cancer.”
This is an active focus of Bandera’s research. She is just getting “The Jersey Girl Study” off the ground, which aims to examine the genetic and environmental predictors of breast development in 9-and 10-year-olds. Some of the factors being evaluated are diet, physical activity, body size, environmental exposures, and prenatal factors. Bandera is particularly interested in evaluating whether a vegetarian diet and/or eating organic foods will have an impact on hormonal levels and breast development in these girls. “This is something that has received little attention, despite concerns of hormones in milk, meat and eggs.”
Bandera is collecting data through a questionnaire, as well as detailed body measurements, and saliva and urine samples.
Her primary advice for boomers is: “Teach your children well.” Among other things, that means showing them how to eat properly and how to cook from scratch, an activity she enjoys with her own two children.
Among her other recommendations: Work to change your kids’ sedentary lifestyles. Put some effort into providing good snacks and changing the lunch offerings at your local schools.
One of her own studies, funded by the National Cancer Institute, is looking at the effect of diet—with a particular focus on phytoestrogens and alcohol—on endometrial cancer risk. She has finished collecting data from almost 500 women who have had an endometrial cancer diagnosis and 500 controls, and is analyzing results. Her collaborators are epidemiologists from Memorial Sloan Kettering and the New Jersey Department of Health and Senior Services. She is also the principal investigator on a study on the role of phytochemicals — naturally occurring chemicals found in foods like fruits, vegetables and grains — and green tea on ovarian cancer risk. Participants in both studies are New Jersey residents.
Bandera is a firm believer that our lifestyle choices have a significant impact on cancer prevention. The basic message of the American Cancer Society — eat five a day, avoid overweight and keep moving — may seem overly simple in our complex world. But it’s a message worth repeating again and again — because like the anti-smoking campaign, one day it will take hold and save thousands of lives.
If you want to know more, turn to pages 20-29 of the American Cancer Society’s report for an alphabetical listing of foods, nutrients and lifestyle factors and their relationship to specific cancers.
The Magic Bullet
Screening, screening, screening. It’s the magic bullet in the cancer war according to surgical oncologist David August.
And as baby boomers progress through their 50s and 60s, screening will be even more crucial, he contends, because the incidence of most “common cancers” rises precipitously as we age. Colorectal, breast, prostate and lung cancers are relatively uncommon in people younger than 50. “More than half of those diagnosed with breast cancer are older than 65 and more than half with colon cancer are over 60,” he says.
But don’t think the rising incidence is a sign that medicine is doing a bad job, he comments. “It’s actually a sign of medicine’s success in extending life.” August observes that between 2020 and 2025, predictions call for cancer to overtake heart disease as the number one killer.
A boomer himself, August promotes mammograms, PSA tests and digital rectal exams, and colonoscopies as life-savers for this age group, explaining that three hours a year is all the time a basically healthy boomer needs to spend on screening activities that can catch a cancer before it even starts or in its early stages. But just in case you thought you could go the non-invasive route for colon cancer screening, “Virtual colonoscopy is available, but not perfected,” he explains, “and it’s not intended to replace colonoscopy but to screen for polyps and determine who needs
Because colonoscopy is off-putting for many, August is working with a team including David Foran, PhD, RWJMS professor of pathology and laboratory medicine, Daniel Notterman, MD, University Professor and RWJMS chair of pediatrics, and the Siemens Corporation, to develop a multifactorial, noninvasive approach to assess risk for colon cancer. Based on this score, a patient would be directed for further screening if needed. Factors that will be considered include: blood tests, a physical exam, risk characteristics, imaging studies, occult blood screening of stool and examining stool for DNA.
August hopes a trial of this method will be launched in a year or two — after the team learns how to combine these factors and score them. Participants will get a numerical score, and then be followed to assess the accuracy of the process.
In conjunction with screening, he advocates simple dietary modifications: “Low fat, minimal red meat, lots of fresh fruits and veggies — there’s evidence these changes reduce the risk of colorectal cancer. And increase vitamin D and calcium intake — it may contribute to overall health and possibly reduce colorectal cancer risk.” His advice also includes a list of don’ts:
- Although a daily aspirin reduces the risk of colorectal cancer, the risks outweigh the benefits if you’re an average boomer.
- Sunbaths are still a no-no despite “apocryphal arguments” that the Vitamin D in sunlight lowers your chance of developing certain cancers.
- Multivitamins should not take the place of dietary modifications.
Changing how you think about food and activity is key to lowering your cancer risk, he says. “There’s good research that says if you ask someone what he eats each day for two weeks and then you feed him that diet for two months, it will result in weight loss.” In other words, most of us vastly underestimate our food intake.
Along with diet changes, August promotes greater activity in the “non-active” time of your day (the part not already devoted to exercise). Such activities as walking the steps at work, parking in a distant spot in the parking lot, etc. “become embedded in your lifestyle and resonate throughout your life — they change other things.” He takes his own advice to heart and walks the six flights at Robert Wood Johnson University Hospital while simultaneously conversing with students. August is not the one straining to catch his breath.
The surgical oncologist strongly recommends less invasive surgery for colorectal cancer. Major clinical studies show that “laparoscopic surgery is no better or worse than traditional open procedures; and that smaller incisions are the way to go,” he says. “In advanced disease, we take a very aggressive surgical approach to recurrent metastases of the liver and lungs, which has yielded some positive results.”
The problem, he states, is that there is no effective systemic treatment for colon cancer, as there is for breast cancer. “Just in the last five years or so, new agents have become available for breast cancer. Using systemic approaches, we’ve been able to cure more advanced disease or convert it into a chronic problem.”
In concluding, he returns to the topic of obesity which he says is a major risk factor for cancer mortality because the surgery is less precise, there is a higher rate of complications and the dosing for chemotherapy and radiation is very
difficult. “We’re not smart enough to tailor the treatment effectively,” he comments.
The surgeon says patients often come in to him and say, “I did all the right things, doc. Why did this happen to me?”
His answer (and it is a sincere one) is: “Had you not done all the right things, it might have happened sooner or been more severe.” While two thirds of cancers can be traced to tobacco exposure, diet and lifestyle, and 20 percent are attributed to environmental exposures and genetics, he says “we have no idea where the other 20 to 25 percent come from.”
“So if you lived the perfect life, you still have a 25 percent chance of getting cancer.”
This boomer surgeon has recently lost more than 10 pounds over 18 months, so we know that he knows how to follow his own prescription for health and longevity.