Q: Lately I've heard discussion about how what you eat can influence not only your overall health, but specifically your chances of getting cancer. What foods are we talking about?
A: We're not talking specific foods as much as dietary patterns. We're concerned about an epidemic of obesity in this country among both the young and old. You're talking about an imbalance between the food we eat and the exercise we get.
Q: Does obesity cause cancer?
A: You can't actually say it causes cancer ... (but) obesity is associated with a greater incidence of certain cancer. We're looking at what factors are associated with an increased risk in the population. The obesity and sedentary lifestyle are the two things that seem to be the most dominant in terms of cancer and cardiovascular disease.
Q: We've always been told that it takes both diet and exercise to be healthy, but what kinds of foods should we definitely include a lot of and what should we exclude to lower our health risks?
A: The American Cancer Society's dietary guidelines for 2002 talk about eating a variety of foods -- with an emphasis on "variety." You need to eat fruits, vegetables, whole grains, and limit our consumption of red meat, especially those that are high in fat or processed with saturated fat.
Q: So this is nothing particularly new?
A: Right. Unfortunately if we go back to food patterns, our genes haven't changed as rapidly as our environment has. An abundance of food and labor-saving devices has added to the problem. We've increased calories and decreased activities.
Q: Does how foods are prepared make a lot of difference?
A: Our wisest choice would be picking up an apple or carrot and eating them, if not raw, then intact, as opposed to highly processed. Instead of cookies, we'd be better off picking up fruit, eating whole-wheat bread instead of white bread. As far as preparation goes, we would be better off not preparing things with high-fat ... or high-calorie items added like we do here in New Orleans. Legumes -- beans -- are not bad for you, but we like to add high-fat sausage to our red beans.
Q: What other patterns are adding to the obesity problem?
A: We tend to go overboard on portion sizes. The food pattern I see is the biggie sizes. We're an economically minded country and like to get a lot for our money. The portions are large in restaurants. We tend to see that when we're out and bring that into the home.
Q: Are there some foods that are better than others in terms of things like antioxidants?
A: Fruits and vegetables do contain antioxidants and other compounds that may be protective, but we're not to the point where we can identify or recommend intake of supplement X or vitamin X [for, say, preventing cancer]. We're much better off eating fruits and vegetables that have an abundance of these compounds.
Q: What would those foods be?
A: The (American Cancer Society) guidelines emphasize the word "variety" -- fruits and vegetables, leafy greens, citrus fruits, melon, kale, broccoli, spinach, nuts, low-fat dairy products. Part of the problem is that sometimes people see one food that has been identified in one study as being good for one thing, but they tend to overlook the need for variety. If you're eating a variety of fruits and vegetables and whole grains, it is unlikely you are eating a diet high in saturated fats.
Q: Are there foods that work specifically on keeping cells healthy so they don't become abnormal or cancer cells?
A: There are experimental models and animal studies that talk about a cellular level, but that is way beyond the scope of this discussion right now. Most important for this are prospective studies, where you identify the food habits of a group of people and wait until they develop the disease or disorder and try to identify what they did for the past 20 years to increase the risk of cancer. The studies going on right now that tell us what we should be doing are the clinical trials (in which medications or other interventions are used on one group and not another). You wait seven to eight years and then you compare the group that had the intervention and those that didn't have the intervention so you can show conclusively that it made a difference.
Q: But we tend to want quick answers and speedy results from trials.
A: Food behavior is very difficult to change, and it's difficult to measure. We're humans, we're not an animal model where everything can be controlled. It's also eating, so it's not like you can take a pill (and determine differences among groups). It's very difficult to measure.
Q: Where do we start?
A: Parents are important, and parents setting an example is probably one of the most important things they can do for their children -- giving them the right food choices, which probably means more meals at home. ... Also, read labels; there is a lot of information at the store site on the product. Look at the ingredients.
Q: Talk about nutritional supplements in preventing disease and cancer.
A: As far as a one-a-day multiple vitamin supplement, there is not added insurance to that, but if your diet is inadequate, it is not harmful. There is no scientific proof that taking supplements can lower anyone's risk. ... There are other substances that have been identified in food that can lower one's risk, but it's not just one item or one compound that works; we need a very varied diet.