Weight & Cancer – is there a link?

cancer-risk-obesityWe all know that Americans (and the inhabitants of other developed nations) are getting heavier. I don’t need to scare you with a lot of statistics for you to realize that we now have a major problem with people carrying excess weight.

One thing you may not have considered is the link between being over-weight and cancer – and more importantly, what you can do for prevention.

Studies have proven that a 5-point increase in Body Mass Index (BMI) is associated linearly with the following 6 cancers:

  1. Uterus
  2. Gall bladder
  3. Kidney
  4. Cervical cancer
  5. Thyroid cancer
  6. Leukaemia

Body Mass Index is also associated non-linearly with 4 other cancers:

  1. Liver
  2. Colon
  3. Ovarian
  4. Breast cancer after menopause

BMI is a person’s weight in kilograms (kg) divided by his or her height in meters squared. Overweight is a BMI of 27.3 or more for women and 27.8 or more for men. Obesity is a BMI of 30 or more for either sex (about 30 pounds overweight).

Cancer risk is influenced by multiple factors including genetics, lifestyle (ex. tobacco usage, nutrition, exercise, UV exposure, etc.) and your environment (ex. pollution, radiation, certain infectious agents & chemicals, etc.).

Today, we are going to look at foods that either protect against or increase the risk of the above mentioned cancers. Prevention isn’t about one “miracle food”. We want to add more foods that reduce risk and limit foods that increase risk while striving for a lifestyle that encourages a healthy weight.

Fruits and vegetables are associated with a reduction in the risk of mouth, throat, larynx, oesophagus, stomach and lung cancers.   I try to eat about 370g of vegetables per day with 1-3 servings of fruit. I also focus on variety and foods high in fibre.

Red meats (conventionally raised) are associated with an increased risk of cancer. For example, the risk of colo-rectal cancer increases by 12% for each additional 100g of red meat over 500g per week. Aim for less than 500g of red meat per week (no more than 4 servings). Alternate red meat with poultry, fish, eggs, dairy, mushrooms, nuts / seeds and legumes for protein.

Cold cuts are also associated with an increase in the risk of cancer. Colo-rectal cancer increases by 17% with each additional 100g per day of cold cuts above 50g. What more can I say – Limit Cold Cuts!

Alcohol is associated with an increase in the following cancers: mouth, throat (pharynx), larynx, oesophagus, colo-rectal, liver and breast cancer. Risk goes up with the amount consumed and risk is already statistically significant with one serving per day.

Too much salt leads to a 41-68% increase in the risk of developing stomach cancer.

Losing weight or maintaining a healthy weight is now considered a vital therapeutic objective for the prevention of digestive cancers, especially if you are already at risk (in other words, it runs in your family).

Limit activities that don’t allow you to move (ex. screen time). Adults should aim for 30 minutes of moderate exercise (ex. walking) five times per week OR 20 minutes of intense exercise (ex. running) three times per week. Children should get an hour of exercise or physical play-time every day.

In summary, remember these three priorities when it comes to cancer prevention:

  1. Enjoy a balanced, healthy diet with lots of variety, vegetables, fruit & fibre
  2. Limit alcohol, red meat, cold cut & salt consumption
  3. Enjoy regular physical activity & strive for a healthy weight


~Thank you to Dr. Didier Souveton for presenting this information at the Canadian metabolic balance® conference on October 21, 2015.