Mediterranean diet

Substituting Western-type diet products with Mediterranean could also decrease the risk of other chronic diseases. (© fascinadora -

Researchers say that pesticides and contaminants found on produce and whole grains can weaken your immune system.

OSLO, Norway — There’s been much fanfare surrounding the Mediterranean diet in recent years, which typically consists of fruit and vegetables, whole grains, nuts, olive oil, and fish. Now new research offers some alarming warnings. Switching from an ordinary “Western” diet to a traditional Mediterranean diet may triple one’s intake of environmental contaminants, the stunning new report reveals.

Many studies have hailed it as a healthy alternative to typical diets (high in saturated fat from red meat and dairy), making it highly popular with health-conscious individuals. In a surprising twist, however, authors of this new report say fruit, vegetables, and whole grains are the source of most of these toxins when they come from traditional farming techniques. Meanwhile, fish contains many fewer contaminants.

The international team says the Mediterranean diet could weaken the human immune system, fertility, and even stunt the growth and development of children. The study, led by scientists at the University of Oslo, looked at British students who follow the diet. They conclude that farming everything in a Mediterranean diet organically slashes the intake of these contaminants by 90 percent.

Researchers tested participants’ urine and investigated which contaminants were present in the foods they ate. Project Manager Carlo Leifert, a visiting professor at Oslo, says that several of the environmental contaminants discovered may affect hormones in the body.

“Many of the synthetic pesticides detected in both food and urine samples in this study are confirmed or suspected endocrine disrupting chemicals (EDC). The 10 times higher pesticide exposure from conventional foods may therefore provide a mechanistic explanation for the lower incidence of overweight/obesity, metabolic syndrome and cancer associated with high levels of organic food consumption in epidemiological/cohort studies,” Leifert explains in a university release.

Are all these toxins coming from the food?

The researchers say it is too early for health officials to start recommending against the Mediterranean diet. They note that the study of 27 British students was small and more research is necessary to confirm the results.

“This study provides clear evidence that both our diet and the way we produce food may affect the level of exposure to synthetic chemical pesticides and ultimately our health,” adds Chris Seal, a professor from Newcastle University.

A person’s intake of environmental contaminants also comes from other things such as skin creams and even the air we breathe in. The study did not account for these factors, although the researchers say it is unlikely to have affected the results.

“One of the difficulties of assessing the public health impacts of dietary exposure to pesticides is that once pesticides are widely used in food production everybody gets exposed. This study demonstrated the potential of using organic food consumers as a ‘low pesticide exposure control group’ to investigate the effect currently used and newly released pesticides on public health,” explains Dr. Leonidas Rempelos.

Fan of Mediterranean diet? Go organic.

Study participants ate “ordinary” British foods for a week before the study began and had to log what they ate. The team then took urine samples from each person before sending them off to a farm in Crete for two weeks. When they arrived, researchers split the group into two groups, one who ate food cultivated normally and the other eating organic produce. They had urine samples taken again before returning to the U.K. and their normal diets for another week.

“There is growing evidence from observational studies that the health benefits of increasing fruit, vegetables and whole grain consumption are partially diminished by the higher pesticide exposure associated with these foods. Our study demonstrates that consumption of organic foods allows consumers to change to a healthier diet, without an increased intake of pesticides,” concludes Professor Per Ole Iversen from the University of Oslo.

The findings appear in the American Journal of Critical Nutrition.

South West News Service writer Gwyn Wright contributed to this report.

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