The higher the obesity, the higher the risk of cancer.
The International Agency for Research on Cancer said that overweight increases the chances of several types of cancer.
Researchers and oncologists analyzed nearly a thousand studies looking at the link between cancer and weight. The analysis was published late last month.
"This comprehensive assessment highlights the importance of maintaining a healthy weight as a means of reducing the chances of getting several different types of cancer," said Béatrice Lauby-Secretan, co-author of the analysis.
The results of the agency's study confirmed evidence from a 2002 assessment that maintaining a normal weight reduces the chances of colon cancer, rectal cancer, uterine cancer, esophageal cancer, kidney cancer, and breast cancer after menopause.
The analysis also provided sufficient evidence confirming the link between overweight and risk of liver cancer, pancreatic cancer, ovarian cancer, and cancer at the top of the stomach.
"The higher the obesity, the greater the risk of cancer," said Rudolf Kaaks of the German Cancer Research Center.
In contrast, the data failed to confirm whether weight loss reduces the risk of cancer.