(CBS) -- Diabetes and having a high body mass index or BMI cause nearly 6% of cancers worldwide. That's according to researchers in London.
"800,000 cancer cases each year that are attributable to overweight, obesity, and diabetes," says study author Dr. Jonathan Pearson-Stuttard.
The study looked at data on 175 countries and linked diabetes and obesity to 18 cancers, with liver, breast, endometrial and colorectal cancer accounting for the most cases.
Diabetes and obesity affect sugar levels, inflammation and hormones which can increase cancer risk.
Researchers say the number of cancer cases related to diabetes and high BMI is likely to keep increasing unless people around the world start getting healthy.
We must take big, big structural and innovative approaches to prevent obesity and diabetes. We have got a long way to do on that specifically tackling poor diet, says Pearson-Stuttard.
And with more than 2 billion people around the world overweight and about 420 million diabetics, researchers say it's time to get healthy now.