Environmental Pollutants Linked to Insulin Resistance

Imagine. You add more fish in your diet, because you want to eat more healthfully, and after a month you notice you have gained belly fat. You go to your doctor, and after having some tests done, he or she tells you that you are now having trouble regulating your blood sugar. After asking you a few questions, your doctor discovers the culprit—you have been exposed to too many environmental toxins. 

This is exactly what happened to rats who ate fish oil contaminated with high levels of chemical pollutants. Although we look nothing alike, our makeup (as humans) has a lot in common with rats, which is why rats are studied so often. There have been numerous studies linking environmental toxins to weight gain in humans (and rats). However, the study I’m about to tell you about is the first to associate high levels of persistent organic pollutants (POPs) with the onset of insulin resistance.
A little over a year ago, European researchers published a very interesting paper in Environmental Health Perspectives. Theses scientists fed male rats for 28 days with fish oil from farmed Atlantic salmon. Half of the fish oil was free of chemical pollutants; the other half contained persistent organic pollutants.

Within 28 days, the rats who were fed the fish oil laden with chemical pollutants gained weight (belly fat), became insulin resistant (a precursor of diabetes), and had higher cholesterol, triglyceride, and other fat levels that affect the liver. Not only were these rats less able to process fat and sugar, scientists noted that a number of the genes that regulate metabolism were also altered.

For many years, POPs have been shown to negatively affect the health of people and animals. This is why POPs were banned in Europe and in the U.S. roughly 30 years ago. POPs include organochlorine pesticides, polychlorinated biphenyls (PCBs), dioxins, and furans.

Although called “organic,” they are nothing like a health-enhancing piece of organic fruit. Plus, POPs can remain in the environment—and your fat cells—for years. So they can still be found both in water in polluted areas and in some fatty foods, including dairy and fish. 

Now, I’m not recommending that you don’t eat fish or take fish oil. Both confer enormous health benefits and are available from pure, uncontaminated sources. However, you should be aware that any food which isn’t pure can put your health at risk by exposing your body to toxins. I also encourage you to have your doctor check your blood mercury level if you are eating a lot of fish to be sure you are not getting mercury toxic. I see so many of my own patients with mercury toxicity from eating fish, that I now discourage my patients from eating much fish of any type at all.

If you notice unexplained weight gain or if you go to your doctor and he or she tells you that you are becoming insulin resistant, consider whether environmental toxins could be to blame. If so, consider seeing a doctor who specializes in environmental medicine and can help you clear your system of these hidden health-robbers.  


Ruzzin, J., et. al., Persistent organic pollutant exposure leads to insulin resistance syndrome Environmental Health Perspectives, Apr 2010 118(4),


About Dr. Soram Khalsa

As an MD, Dr Soram specializes in Integrative Medicine combining diet, nutrition, acupuncture, herbs and nutrition. Visit Dr Soram’s Healthy Living Store where you’ll find high-quality nutritional supplements: