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
Laboratory tests conducted to ascertain exact cause of deaths in north central Kogi state, health official says
Health official decries lack of funds to fight malaria, appeals for donations to help fight disease
Surge in heroin use, other opioids seen as main reason for increased deaths
A separate 40-year-old male was returned to the zoo in Rajshahi where there are only females.
Millions of eggs have been pulled from supermarket shelves across Europe and dozens of poultry farms closed since the discovery of fipronil, which can be harmful to humans, was made public on August 1.
An immediate cull was ordered for all chicken, ducks and quail within a kilometre (0.6 miles) of the infected poultry in San Luis town, north of Manila, said Agriculture Secretary Emmanuel Pinol.
Heat due to long-term temperature rise, strong El Nino, report says
Multimillion dollar project aims at turning dirty riverbanks of Addis Ababa into attractions
Dutch authorities have temporarily closed 138 poultry farms and may cull millions of chickens.
Recalls in Germany, Netherlands and Belgium and criminal inquiry launched as tests show high levels of insecticide profile
WHO has recorded 419,804 suspected cholera cases in Yemen since April 27
More than 10,000 people had to flee raging fires in southern France this week, and several villages were evacuated in Portugal just weeks after another blaze killed more than 60 people there.
WHO says 396,086 suspected cholera cases have been recorded in Yemen
Japan has the highest suicide rate among Group of Seven (G7) advanced countries and the government describes the situation as "critical" in a country where more than 20,000 people kill themselves every year.
At present people have no option but to take lifelong, daily doses of anti-retroviral therapy (ART) which keeps the HIV virus under control, but does not kill it.