Obese and overweight people are more likely to develop colon polyps, a possible precursor to cancer, than slimmer people, according to an international study.
Previous studies have made the connection between obesity and colon cancer, a link recognized by the US National Cancer Institute. But the current study, which appeared in the American Journal of Gastroenterology, is the first to point to a higher risk of colon polyps - also known as adenomas - in heavy people.
"Because there is a known association between obesity and cancer, there is a logical extension to expect a connection between obesity and the step before cancer, which is adenoma," said Hutan Ashrafian from Imperial College, London, who co-authored the study.
Ashrafian and his colleagues analyzed data from 23 studies involving more than 100,000 people across the United States, Asia and Europe, looking at the relationship between polyps and body mass index, or BMI, a measure of weight relative to height.
All the studies followed World Health Organization (WHO) guidelines that define people with a BMI over 25 as overweight and above 30 as obese.
In most studies, polyps were identified during colonoscopy procedures while two large studies used self-reported questionnaires.
Overall, researchers found that 22 percent of overweight and obese people had colon polyps, compared to 19 percent in people of normal weight. The polyp risk grew with increasing BMI.
"The findings suggest that obesity may be having an effect (on cancer development) much earlier than we thought," said Ashrafian, who with his fellow authors recommended timely colon cancer screening for overweight and obese people.
The findings couldn't say whether obesity causes polyps by itself, but if it does, that may be bad news for a world where obesity is on the rise.
According to the World Health Organization, about 500 million people worldwide are obese. Colon cancer killed more than half a million people worldwide in 2008, WHO figures show. SOURCE: http://bit.ly/QgLHRO
Hundreds of thousands of climate activists have descended on Paris ahead of the UN Climate Conference and are preparing to defy a ban on street protests joining thousands of protestors around the world.
'This is all bad news for the planet,' head of the World Meteorological Organization says
UN agency calls for urgent climate deal as hundreds of thousands fall victims to weather disasters
Fifty grams of processed meat eaten daily increases risk of colorectal cancer by 18 percent, say experts
COP21 conference aims at securing a pact on greenhouse gases that would limit global warming to two degrees Celsius over pre-industrial times.
Earth is on track for average warming of 2.7 degrees Celsius by 2100, exceeding UN's anticipation
The London Project to Cure Blindness was established a decade ago to try to reverse vision loss in patients with age-related macular degeneration
Improvement has been seen around the globe, even in the key tropical rainforests of South America and Africa
Christiana Figueres says there is 1.2 million euros deficit to cover upcoming sessions
Some of the world's major cities, most Pacific island nations are at risk of disappearing due to rising seas
Yemen forces allied to the Houthi have launched a scud missile toward southern Saudi Arabia
Three dozens of fires may cause an ecological catastrophe to Lake Baikal in Russia
National and international slow responses to epidemies show how far the world is from achieving global health security
Call for action in madrassas and mosques around the world is intended to emphasize the role Islam can play in combating climate change
New reports claim parent company Alphabet is attempting to fight malaria and other diseases transmitted via insects
Scientists are predicting that Earth could be heading towards an extraordinary event which would see compasses point south and the sun rise in the West.