We all know, by now, that being overweight puts you at increased risk for heart disease, stroke and diabetes. The truth is that the link between obesity and cancer is just as strong but is less well known. There are lots of factors at play in how and who gets cancer but the Canadian Cancer Society suggests that about half of all cancers are preventable by making some simple lifestyle changes.
Comfortingly putting some control back into your hands. And, on the bright side, you now have one more motivation keep your weight at bay. Obesity is associated with increased risks of the following cancer types. There may be others whose causal link has not been established (but give it time…)
- Colon and rectum
- Breast (after menopause)
- Endometrium (lining of the uterus)
“One study, using NCI Surveillance, Epidemiology, and End Results (SEER) data, estimated that in 2007 in the United States, about 34,000 new cases of cancer in men (4 percent) and 50,500 in women (7 percent) were due to obesity. The percentage of cases attributed to obesity varied widely for different cancer types but was as high as 40 percent for some cancers, particularly endometrial cancer and esophageal adenocarcinoma.” (National Cancer Institute) It is estimated that if every adult reduced their BMI by 1 percent, (which is about a pound or 2.2 kg), it would prevent the increase in the number of cancer cases and actually result in the avoidance of about 100,000 new cases of cancer.
This study is in its infancy but several good theories explain why there is such a link:
- Fat tissue produces excess amounts of estrogen, high levels of which have been associated with the risk of breast, endometrial, and some other cancers.
- Obese people often have increased levels of insulin and insulin-like growth factor-1 (IGF-1) in their blood (a condition known as hyperinsulinemia or insulin resistance), which may promote the development of certain tumors.
- Fat cells produce hormones, called adipokines that may stimulate or inhibit cell growth. For example, leptin, which is more abundant in obese people, seems to promote cell proliferation, whereas adiponectin, which is less abundant in obese people, may have antiproliferative effects.
- Obese people often have chronic low-level inflammation which has been associated with increased cancer risk. (National Cancer Institute)
It is no surprise, then, that the recommendations for weight loss or healthy weight maintenance are the SAME as those for preventing cancer. Cancer affects everyone and there are a myriad of ways that it is out of your hands but it just makes sense to control what you can.
What you can do:
- Maintain a healthy body weight. Keep your BMI between 18.5 and 24.9. Lose whatever excess weight it takes to stay within this range.
- Quit smoking! Know that tobacco and alcohol together are worse for you than either one on its own. And that calories from alcohol can’t be used as energy, they can only be stored as fat.
- Women should drink less than 1 drink a day and men less than 2 drinks a day. A “drink” is: one 350mL (12 oz) bottle of beer (5% alcohol) or one 145mL (5 oz) glass of wine (12% alcohol) or one 45mL (1.5 oz) shot of spirits (40% alcohol).
- Get 10 servings of fruits and veggies every single day
- Consume 25-35 grams of fibre each day (actually track your intake once in a while for a baseline!)
- Reduce sugar (here’s how…)
- Reduce bad fat, red meat and processed meat
- Get at least 30 minutes of moderate activity every day. In addition to protecting against colon cancer, research shows that women may be able to reduce their risk of breast cancer and uterine cancer by getting active.
For the good of all, do what you can to find a way to support cancer research and treatment, the Canadian Cancer Society holds all kinds of fun events to bring awareness, information and raise funds (I am personally going to fun shaving the heads of cops!)
To find out more or donate, visit MyFriendinFood.com