The environmental pollutants we consume may be causing some people to develop type 1 diabetes. Even low concentrations of such pollutants can cause cells to produce less insulin, a new study from the University of Oslo (UiO) has found.
Approximately 400 children and adolescents are diagnosed with type 1 diabetes each year in Norway, and the number of new cases among children and adolescents has doubled since the 1970s. Adults are also diagnosed with this disease.
Type 1 diabetes is an autoimmune disease characterized by the destruction of pancreatic beta cells that produce insulin. The body’s own defense system makes the mistake of believing that these insulin-producing cells are harmful foreign cells that need to be destroyed.
What triggers the onset of type 1 diabetes is still unclear to scientists. Could it be heredity? Diet-related environmental factors, contaminated drinking water or viral infection? Researchers find more environmental pollutants in the blood of children with type 1 diabetes
In collaboration with the University of Tromsø and several research groups in the US, UiO scientists studied the levels of environmental pollutants in blood samples of American children and adolescents diagnosed with type 1 diabetes. They were compared with blood samples from a control group without type 1 diabetes.
“We found that a large proportion of type 1 diabetics had these contaminants in their blood. On average, they also had higher concentrations of several types of environmental contaminants,” says Sophie E. Bresson, PhD student in the Department of Molecular Medicine at the University’s Institute for Basic Medical Sciences. Oslo.
For a deeper study of their results, the researchers used beta cells from rats. Toxic substances were applied to these cells to find out what happened next.
“We found that beta cells produced much less insulin, even after only two days and at very low concentrations of pollutants. When beta cells were exposed to pollutants for a longer period of time, they died. Therefore, we believe that pollutants The environment plays a role in the onset of type 1 diabetes,” says Bresson.
Bresson, Professor Jérôme Ruzzin and the research team recently published their findings in an article in the journal Environment International.
Some of the environmental pollutants studied by the research team, such as PCBs and pesticides, were banned 20 years ago by the Stockholm Convention. However, these substances are found in food, plastics, paints, building materials, soil and water and are only slightly broken down naturally. They can also be trapped by ice, and when the ice melts due to global warming, pollutants are released.
In addition, a number of countries that have not signed the Convention still continue to use these substances to prevent insect attacks on crops.
“Most environmental pollutants we consume through the food we eat. Once these pollutants enter the body, there is unfortunately nothing we can do to destroy them,” says Bresson.
As part of the study, scientists received blood samples from the United States. Can the level of environmental pollutants there differ from the Norwegian one?
“We have no reason to believe that there are significant differences. But we need to find out for sure,” says Bresson.
90% of the environmental pollutants we consume through food come from fish, meat and dairy products, explains Professor Jason Matthews from the Department of Nutrition at the University of Oslo. Scientists note that oily fish such as herring, mackerel, halibut, salmon and trout contain more dioxins and dl-PCB than lean fish fillets. Examples of lean fish are saithe, cod and haddock.
“To start with, eat less meat and choose leaner fish. Organically grown foods will contain fewer trace elements of pesticides because they are not sprayed, but they will still absorb pollutants through water and soil,” Matthews says.