Many patients ask what they can do to avoid cancer. With an estimated one in three Canadians afflicted with cancer, it's clear individually and as a society we need to know what we can do. The reality – through diet and behaviour, we can substantively impact the ‘modifiable risk factors.’

Physical risk factors
• Research tells us that between one-quarter to a third of breast, kidney, colon, esophagus and uterine cancers are related to excess body weight and inactivity

• Cancers of the bladder, lung, oral cavity and stomach are related to poor diet. 

Behavioural risk factors
• It’s estimated that quitting smoking impacts 30% of cancers and resultant deaths. We easily link smoking to lung cancer, but it also boosts the incidence of bladder, cervix, colorectal, larynx, esophagus, kidney, oral and pancreatic cancers. Second-hand smoke contributes to a 20% increased risk of lung cancer in a non-smoker.

• Substantial evidence links excess alcohol consumption to breast cancer, with three or more drinks daily related to a 30% increase. Recent studies suggest increased risk with any amount of alcohol.

• Over-exposure to the sun increases skin cancer risk; tanning bed use is also a major concern.

• Lifestyle modification can prevent approximately 30% to 40% of all cancer cases

• Evidence shows that screening and surveillance can substantively reduce the risk of dying from breast and colorectal cancer, while Pap tests can detect cervical cancers in their precancerous state.

Informed yet not acting
Only 1/3 of us consume the recommended daily fruit servings and when it comes to vegetables, the number drops to 12%. The vast majority come nowhere near the minimum 150 minutes of weekly exercise.

When it comes to something as basic as a Pap test, many women fail to go regularly. Get screened for cervical cancer within three years of any, first vaginal sexual activity; then strictly follow your physician’s advice for your next Pap test.

Despite the ample evidence that a mammogram saves lives, many women don’t make the appointment. As a nation, less than 20% of us regularly screen for colorectal cancer.

Compared to many countries Canadians are doing well, but by eating well, drinking alcohol in moderation, frequent exercise, not smoking, along with recommended screening, we can do better. Awareness is one element…but we must turn it into sustainable healthful behaviours. The ability to impact risk factors is yours to put into action! H&L

Dr. Marla Shapiro, Assoc. Prof., University of Toronto, Dept. of Family & Community Medi-cine; CTV’s Medical Consultant on CanadaAM; Globe and Mail health columnist.