by Dr Albert Lim Kok Hooi
A report prepared jointly by the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) in 2007 details the findings of the most authoritative investigation ever undertaken into the link between lifestyle, diet and cancer. The message is overwhelmingly clear - obesity causes cancer.
Smoking is the most important lifestyle cause of cancer. Obesity ranks a close second. In other words, after smoking, obesity is the highest preventable cancer risk.
We used to say that one third of all cancers can be prevented if smoking were to completely cease. We can now say that two-thirds of cancers – 12 million new cancer cases diagnosed each year in the world – would not occur if we are all transformed to slim, fit non-smokers tomorrow.
Foods to be Avoided
What did the report say about the kinds of food we should not eat to avoid cancer? For starters, we should avoid all processed meats, including bacon (bak kua in our local context) and most sausages. It also advises against eating more than 6gm of salt per day.
One reason for avoiding processed meats is that they often contain nitrates – preservatives that may contribute to the production of suspected carcinogens called N-nitroso compounds. Processed meats also contain high levels of salt, which is linked to stomach cancer.
The fat and thin of it all is this. If you wish to avoid cancer – lung cancer, colorectal cancer, breast cancer, ovarian cancer, uterine cancer, cancers of the oesophagus, kidney, pancreas, the list goes on – stop smoking and maintain a body mass index (BMI) of 18.5 to 23 (as per international 'European' recommendations) – i.e. the healthy range.
Body Mass Index
A word or two about BMI. This figure is obtained by dividing your weight in kilograms by the square of your height in metres.
BMI = weight / height * height
In Asian societies, a woman who is 5 feet tall (1.5 metre) looks suspiciously overweight when her BMI is 23. Endocrinologists and dietitians have come up with our own Asian BMI, which is lower than the accepted BMI.
So, for all you women out there from 15 to 85, please try to achieve a BMI of 18.5 to 21. The nearer the lower figure, the better.
Lots of exercise and a strict low-calorie diet will enable you to achieve many goals : beauty, attractiveness, good mates and a much lower chance of getting cancer, diabetes, hypertension, stroke and heart disease.
What Should We Eat
What then should we eat? Eat 5 portions of fruit and non-starchy vegetables (brussel sprouts, broccoli, cauliflower, celery, mushrooms to name a few) each day and limit refined starchy food. White meat – chicken, turkey, rabbit – is much more preferable to red meat. Most of all, count your calories.
Aim for 30 to 60 minutes of moderate physical activity every day. Brisk walking is the easiest and most accessible activity. Diet and exercise go together. One or the other will not achieve your goal.
The science is there but the interventional methods to achieve a healthy lifestyle are something else. How do you overcome the virtue of white rice (and lots of it) in Malaysian and Asian societies?
They tell me there is 'semangat' (spirit or life force) in rice. White rice is an energy-dense food that is diabetogenic, has a high glycaemic index and a major culprit of obesity and getting cancer!
How do you tell the common folk that their 10 favourite foods are a no-no from the scientific health-wise point of view? Nasi lemak, roti canai, curry mee, wanton mee, burger, doughnuts, fries, char kuay teow, chicken rice and mee goreng are out.
How do you politely reject your mother-in-law's incessant heaping of seconds on your plate? How do you decouple the Asian-African notion of prosperity and a protuberant abdomen?
We spend billions of US dollars a year on research to treat cancer and rightly so. We also spend millions of US dollars on how best to get people to quit smoking and eat wisely and equally rightly so.
Wish we were more successful in our second endeavour.
More info on OBESITY here.