Certain chemical pollutants in food linked to type 2 diabetes

August 18, 2011 in Diabetes & Diabetes Prevention, Nutrition Topics in the News

Certain chemical pollutants in food linked to type 2 diabetes

According to a new study published in Diabetes Care, people with high blood levels of certain pesticides may have a greater risk of type 2 diabetes, especially if they are overweight.

Previous studies have linked diabetes risk with exposure to older pesticides (e.g. ones that are no longer in use) known as organochlorines, PCBs and other chemicals known as "persistent organic pollutants."

Organochlorines are now banned or restricted in the U.S. and other developed countries, after research linked them to cancer and other potential health risks. PCB's were widely used for industrial purposes until 1977, when they were banned in North America. 

However these chemicals stick around in the environment for years and accumulate in the fat of humans and animals.

In North America, diet is the main potential source of exposure, in particular fatty foods such as dairy products, meat and oily fish.

Research in the lab has hinted that some persistent organic pollutants impair the body's ability to regulate blood sugar which may explain the link to type 2 diabetes.

Some of the compounds also have been shown to promote obesity, which is a major risk factor for developing diabetes.

For the study, researchers from Finland's National Institute for Health and Welfare measured blood levels of several persistent organic pollutants in about 2,000 older adults of which 15% had type 2 diabetes. The risk of diabetes was higher among people with the highest blood levels of organochlorine pesticides.

Those with levels in the top 10 percent were about twice as likely to have diabetes as their peers in the bottom 10 percent. But the link appeared to be limited to people who were overweight or obese.

The researchers accounted for participants' age, sex, waist size and blood pressure levels. But they did not have information on diet and exercise habits which could explain the pesticide-diabetes link.

But the overall body of research, say the researchers, suggests a cause-and-effect relationship.

There is a fair amount of evidence that shows that these compounds disrupt hormone function in the body.

Other studies have found that people's blood levels of persistent organic pollutants predict their future risk of developing type 2 diabetes.

The major dietary contributors of these chemicals  are beef, chicken, and pork (34%), dairy products (30%), vegetables (22%), fish and shellfish (9%) and eggs (5%).

Choosing lean cuts of meat and low fat dairy products and using cooking methods that allow the fat to cook off (e.g. baking, broiling, grilling versus frying) will lower the amount of persistent organic pollutants in foods.
