The expanding cancer watchlist now includes people suffering from obesity. According to doctors, there has been a 20 per cent increase in obesity-induced cancer in the city over the past few years.

Breast, ovarian and uterine cancer among women and colon and prostrate cancer among men have recorded a sharp rise due to increased obesity. ?A person overweight by 35 kg is in the cancer high-risk group,? said V.K. Bhartia, bariatric surgeon. ?To avoid the risk, an obese person must undergo a proper weight management programme or obesity surgery.?

?Breast and colon cancer are among malignancies that are directly related to high-fat diet. Lack of fibres in diet usually leads to colon cancer,? said an expert.

Stretching exercises, followed by a half-hour brisk walk, swimming and balanced diet help keep the chances of obesity-induced cancer down, doctors pointed out. Red meat and too much of sugar must be avoided.

Subhankar Chowdhury, head of the endocrinology department of Institute of Postgraduate Medical Education and Research and SSKM Hospital, said: ?The fat tissue is not just an inert storehouse of energy. It also produces several hormones and cytokines (chemical mediators produced by certain cells). Some of these are harmful for the body.?

The risk of death from uterine cancer is six times higher in women suffering from obesity than those having normal body weight. The risk of death from colon cancer is five times more for obese men than non-obese ones.

According to city-based endocrinologist Binayak Sinha, excess fat in the abdomen causes less secretion of Tumour Necrosis Factor Alpha, a chemical mediator which breaks the tumour. ?Also, excess fat cells cause excessive secretion of estrogen hormone, increasing the chances of cancer,? Sinha explained.

Earlier, most patients of uterine cancer were women over 50 years of age and of breast cancer, women between 40 and 60 years. But now, because of increased obesity, women of much younger age are suffering from uterine, ovarian and breast cancer.