A study conducted by The International Agency for Research on Cancer (IARC), the specialised cancer agency of WHO located at Lyon in France, has amassed solid evidence to label obesity as a major risk factor for cancer as the half a million new cases of the deadly disease (481,000) reported in 2012 was caused by a high body mass index (BMI).Reuters

Excess fat in the body can increase the risk of ovarian cancer in women, researchers reveal.

In a report, compiled by the American Institute for Cancer Research and World Cancer Research Fund, every five point increase in the body mass index (BMI) was associated with a six percent increased risk of developing ovarian cancer.

BMI is a number calculated from a person's weight and height, to measure body fat. A body mass index (BMI) of 19 to 25 is considered to be an ideal weight, while BMI above 25 and 30 is taken as overweight and obese.

Nearly 128 studies on ovarian cancer were selected for the study. Researchers looked at 25 studies that analysed the link between ovarian cancer and weight. Of the four million women in the studies, 16,000 women developed ovarian cancer.

"This is an important finding, because it shows a way for women to reduce their chances of getting ovarian cancer," report author Dr Elisa V Bandera, Associate Professor of Epidemiology at Rutgers Cancer Institute of New Jersey, said in a news release. "There is so much we don't know about preventing ovarian cancer, but now we can tell women that keeping to a healthy weight can help protect against this deadly disease."

Ovarian cancer is cancer that starts in the ovaries, the two small reproductive organs situated on sides of the uterus that produces eggs and hormones oestrogen, progesterone and testosterone. It is the seventh most common types of cancer affecting women across the whole globe. According to the World Cancer Research Fund International, nearly 239,000 new cases of the deadly cancer were reported in 2012.

Several studies in the past have linked obesity to an increased risk of different types of cancer. According to the American Society of Clinical Oncology, high birth weight, unhealthy weight gain in adulthood, the process of losing and gaining weight frequently can increase the risk of cancer. Until the date, obesity has been linked to cancers of breast, uterus, kidney, thyroid, colon and rectum, endometrium, gallbladder, oesophageal and pancreatic cancer.

(Edited by Anu James)