Obesity and Cancer

Obesity causes a host of medical problems. Now add cancer to the list.

That obesity increases risk of diabetes, hypertension and ischemic heart disease is well-known. But that obesity can also significantly increase cancer risk is even more chilling news; a 2008 meta-analysis of hundreds of cancer studies shows that 14 to 20 percent of cancer deaths were related to obesity! Fat can kill?

The traditional image of a cancer patient is of a thin, wasted person; so one tends to rationalize that a jolly, plump person would never get cancer. But the truth is otherwise. Among men, those with a BMI points above the normal run an increased colon cancer risk of over 55 percent. Women with a similar increase in BMI have a more than 50 percent increased risk of developing uterus or breast cancer. In both sexes, being obesity increases the risk of cancer of the esophagus, kidney, gall bladder and pancreas. It also increases risk of various types of leukemia’s and lymphomas.

Link Between Fat and Cancer

For over two decades, oncologists have had a hunch that fat spells disaster but they had no real evidence. But in 2008 an article in the Lancet analyzed over 250000 cancer patients across 200 studies. Without any shred of doubt obesity was nailed as a culprit aiding and abetting cancer; and the figures are significant: an increased cancer-risk of 34 to 59 percent in the obese.

What exactly is the link between fat and cancer? There are no simple answers; but fatty deposits are a big source of hormones like estrogen. Excess estrogen can result in endometrial and breast cancer. Fat cells also result in high insulin-like growth factors. These have a role in cell multiplication; some of these chemicals unleash our-of-control cell multiplication and result in cancer. Fat cells produce chemicals that cause inflammatory response may turn into a cancerous response. Basically, the key cause seems to be cell growth and cell multiplication getting “out of control.” Fatty tissue seems to produce chemicals that can affect the delicate balance of the immune system whole role it is to control cell multiplication, cell differentiation and cell death.

Though death spells the ‘end’ for the body; for the body’s own survival, cells have to die after their normal cell life-span and allow young new cells to replace them. Cells continuing beyond their “expiry date” and then going on to multiply could result in cancer. Chemicals produced by fat cells seem to aid the pro-cancer activities of such ‘geriatric’ cells.

Another factor that researchers at the National Cancer Institute, Bethesda, pointed out is that there seems to be a global immune impairment in the obese. Even vaccines do not work as well in them. An impaired immune system is fertile ground for carcinogenesis. In the case of food-pipe cancers, the link may be a little more straight-forward. The obese always have more acid refluxing back into the food-pipe from the stomach. This initially results in inflammation and heartburn; but later, the cells turn cancerous. We don’t have all the answers; but clearly being fat increases your cancer risk.

Will weight loss help reverse the cancer risks of an obese person or will it like bolting the stable after the horse has fled? We do not have the answer yet; but if you are obese and do not have any health challenge yet, get to the right weight and shape. A diet of vegetables, fruit juices, roughage and exercise – both part of any sensible weight management program – themselves have an anti-cancer effect; not to mention the salutary effects on the heart, blood pressure, glucose metabolism and so on.
Stem obesity epidemic

What does this news hold for Indians? Food shortage or no, 10 percent of our population is obese. We are already racing ahead of other nations by posting record incidence and prevalence of diabetes, ischemic heart disease, osteoarthritis, osteoporosis and so on. If we do not stem the obesity epidemic, we could be contenders for the cancer title as well.

So what do you do, did you ask? Step on the weighing scales and check your weight. Weight in kilograms divided by height in meters squared, gives BMI. For Indians, a BMI of 23 is fine. If you are at BMI 28 or more, then cut down calorie intake, start walking and exercising, increase anti-oxidants in your diet, take a good vitamin, sleep adequately and learn to find inner happiness; yoga, reading positive mental attitude books, joining laughter clubs, all are fine! Choose to be fit and firmed up; and not fat and flabby; and you will be fine!.