As an oncologist, geneticist and professor of medicine, Theodora Ross, MD, PhD, spends her days studying cancer risk and treatment. But as a woman, she also understands the issue firsthand: she is the carrier of a BRCA1 mutation, which leaves her genetically predisposed to breast and ovarian cancer. In her new book, "A Cancer in the Family: Take Control of Your Genetic Inheritance," Dr. Ross takes on the topic from both a scientific and personal perspective. And in this piece for mindbodygreen, she explains how lifestyle habits can make a real difference in your cancer risk.
The humor writer Erma Bombeck once said that as she aged, her only reason to exercise was so that she could hear heavy breathing again.
But she said that in the 1980s, and since then more data has been collected that suggests another, bigger benefit: exercise, among other lifestyle choices, can also help prevent cancer.
Of course, we can all agree that cancer can result due to the inheritance of mutant genes, plus later random bad luck, that leads to more DNA mutations. There are now many known inherited mutant genes that run through families to cause colon, breast, pancreas, skin, kidney and other cancer syndromes. (So there's actually another healthy habit you can adopt: continuous inquiry into your family history to determine if you might be at risk for inherited cancer.)
Along with inheritance and random bad luck, there are also several environmental stresses that cause cancer, including much sun, radon, asbestos and second-hand cigarette smoke.
However, the idea that cancer is fate and we are simple victims, is at best a half-truth. Every day we make choices that modify the development of cancer.
What the research really shows about cancer prevention
Too many calories, too little activity, too much alcohol, missing our cancer screens and of course, smoking, all increase our risks for cancer.
But despite what you might have read across the internet, not all reports of cancer causes are supported by evidence. For example, phones, plastics, powerlines and emotional pressures have been touted as cancer causing by some. But these proclamations are not supported by evidence. So because of this lack of evidentiary support, official cancer prevention guidelines do not recognize them as risks.
It does, however, stand to reason that too much stress can put us into a tailspin and lead to problematic lifestyle choices. For example, when I’m in a good place, I get my flu shot, do the colonoscopy, go to the dentist and vote (even in the midterms). When I’m stressed, I don’t have the time to floss or to vote. Even worse, my emotional eating kicks in and the inhalation-of-potato-chips-over-the-sink activity interferes with maintenance of my healthy weight.
So what to eat or not to eat? That is the question. Very few specific foods have been convincingly shown to increase or reduce the risk of cancer—with the exception of smoked meat leading to a modest increased colon cancer risk.
For one, it’s difficult to design studies that can accurately look at the effect of a single food item. This is because our diets include various foods, and those foods consist of many different compounds that could affect the risk of cancer.
The way food intake is measured is another difficulty that can push poor epidemiologists over the edge. Many studies use "food-frequency questionnaires" which ask subjects how often and how much they’ve eaten specific foods. But this doesn’t take into account other lifestyle factors that are important in cancer risk, such as being sedentary, smoking tobacco and drinking alcohol. People who enjoy the couch, the sauce and the tobacco too much have lower intakes of fruit and vegetables. If higher cancer risks in those people are observed, it’s hard to detangle the effects of one from the others.
Still, there are a few general lifestyle habits that research shows can lower your risk:
- Continuously learn about your family’s cancer history to know how to manage your genetic risk.
- Don’t smoke.
- Exercise and manage food intake for a healthy weight.
- Avoid excess alcohol.
- Immunize your kids for HPV and get immunized if you’re under the age of 30.
- Screen for early cancers (Pap smear, colonoscopy, and mammography).
- Limit UV exposure (avoid tanning beds and use sunscreen).
In the end, it all comes down to DNA damage. Cancer results from wear and tear on our DNA. DNA encodes the instructions for how cells should behave and every time a cell divides those instructions are copied. Every copy leads to mistakes that if not repaired result in DNA damage.
The habits that increase DNA damage are the top habits to break. As we age cellular stresses, such as UV rays from tanning beds, or other choices, such inhaling the cancer-causing chemicals of tobacco, damage DNA. This damage builds up over time. If damage to the DNA is located at cancer prevention genes such as a BRCA gene, cells will multiply out of control and develop into cancer.
If an Erma Bombeck-like motivation to exercise or make other healthy choices works for you, adopt that incentive. Using healthy behaviors to decrease our cancer risk won’t just help us live longer without cancer—it'll also have the side effect of a healthier, more productive and hopefully, happier life.