Is there a link between environmental toxins and diabetes?
There are some well known, accepted risk factors for diabetes, such as diet, obesity, lack of exercise, smoking, family history and ethnicity. But naturopath and medical herbalist Rosanne Sullivan says emerging research over the last nine or 10 years shows there “may be a new kid on the block”, and that’s environmental toxins.
In her work at the Wellbeing Centre in Auckland, Rosanne says she sees more and more people who aren’t well because of exposure to toxins in the environment, such as painters, builders, people who have worked on orchards or farms, or been exposed to toxins through food, water or air.
And she shared some alarming statistics about diabetes at a recent talk at our shop, including over 200,000 diagnosed cases of diabetes annually in New Zealand, 100,000 undiagnosed, and the fact it’s three times more prevalent among Maori and Pacific Island people here.
The World Health Organisation estimates nine percent of the global population aged 18 plus has diabetes and projects it will be the seventh leading cause of death by 2030. About 347 million people worldwide have diabetes, with type two diabetes accounting for about 90% of cases.
Type one diabetes is an autoimmune condition where a lack of insulin production means blood glucose levels go outside the normal range. In type two diabetes the body either doesn’t produce enough insulin or cells don’t recognise insulin, so it’s used ineffectively by the body, resulting in high levels of glucose in the blood. When cells become resistant to insulin, that’s the pre-diabetic stage.
Rosanne detailed some of the recent research exploring a link between environmental toxins and diabetes, including the long term US National Health and Nutrition Examination Survey. An article about the 1999-2002 survey of 2016 adults found a strong association between serum concentrations of six persistent organic pollutants (POPs) and the prevalence of type two diabetes.
“Persistent organic pollutants (POPs) have become widespread environmental contaminants and now represent a global problem,” the article says. “The toxicity of these pollutants in humans and wildlife is enhanced by their persistence in the environment and their bioaccumulation potential in the tissues of animals and humans through the food chain. POPs include a variety of man-made chemicals. Some POPs, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and several organochlorines used as pesticides have been highlighted by international organisations as being chemicals of concern.”
A 2006 study of US Air Force Vietnam War veterans exposed to dioxin (a herbicide contaminant in Agent Orange), found evidence of a diabetes-producing shift in the fatty tissues of those exposed. This effect also showed up among a control group whose exposure levels didn’t markedly differ from the general US population, so the researchers say the potential health hazard around dioxin at public exposure level should also be taken seriously.
Two years ago a study of plasma polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), and hexachlorobenzene (HCB) concentrations in 1095 US women who were blood tested as free of diabetes in 1989-1990, identified 48 incident type two diabetes cases up to June 2008. Pooling the results with prospective studies totalling 842 cases, the researchers found that HCB and total PCBs were associated with diabetes.
And in a study of the association between diabetes and PCBs and chlorinated pesticides among an adult native American population, there was an association between serum PCB and pesticide levels and diabetes among that population after adjustment for age, BMI, serum lipid levels, gender, and smoking.
Like the other studies, this one didn’t establish cause and effect, but the authors said “there is a growing body of evidence that environmental exposure to persistent organochlorine compounds is associated with elevated incidence of this disease.”
Persistent organic pollutants – of which there are hundreds including PCBs, DDT and dioxin – are among a wide range of potentially harmful toxins Rosanne raises concerns over. Others she mentions include endocrine disrupting chemicals (EDCs), which interfere with the natural function of our hormonal systems; about 150 known thyroid function disruptors; phthalates (listed in the Environmental Working Group’s EDC Dirty Dozen); mercury and other heavy metals.
Our blog has further reading about endocrine disruptors and their potential health effects.
The key sources of these toxins are agriculture and industry and consumer products, and we’re exposed by touch and consumption. Babies are exposed to toxins passed on via the placenta – Rosanne says the placenta was previously thought to protect babies from toxins, but it’s now known that the baby shares what’s in the mother’s bloodstream.
She says because only a low percentage of the more than 80,000 industrial chemicals in daily use worldwide have been tested for toxicity, the question is no longer who is at risk, but to what extent?
In light of this she recommends looking at the sources of toxins, which for POPs include animal fat, non-organic meat, dairy, chicken and eggs. Animal fat is also a common source of exposure to DDT, she adds, as it was applied to crops in earlier decades before being banned here in 1989.
Sources of PCBs include farmed US salmon, non-organic meat, dairy, eggs, breast milk and dust, while dioxins are by-products of wood manufacture, pulp and paper mills, and pesticide use, she says. We can be exposed through non-organic meat, eggs and contaminated soil, says Rosanne.
And another EDC to feature on the Environmental Working Group (EWG)’s Dirty Dozen List is BPA (bisphenol-A), which Roseanne says is found in some Tupperware, polycarbonate plastics and the lining of tin cans.
Check our blog for more about the debate over the safety of BPA.
A common source of mercury is amalgam tooth fillings more widely used before 2000, she says.
She stresses the research and literature on the potential harm of toxins in relation to diabetes is emerging, but she finds it compelling. She’s a strong advocate of the precautionary principle, which says that potentially harmful chemicals should be avoided if there is any doubt over their safety.
These are her tips for reducing exposure to some of the toxins mentioned:
- Avoid pesticides by trying organic food where possible.
- Kick plastics by storing food in glass, drinking from non-plastic bottles, not microwaving in plastic containers and not using plastic food wrap.
- Detox your home – go fragrance free, buy cleaning products that are free from nasty chemicals, ventilate your home to counter off-gassing from carpets and furniture, avoid deodorisers and plug-in insecticides, and allow drycleaning to off-gas for two days before wearing the clothes. Ecostore has a wide range of fragrance free products and we avoid using nasty chemicals in our products.
- Review your personal care products to avoid parabens, and avoid fake tan (which she says can be an EDC) and if you apply nail polish, do it outside.
Use these links for more reading about diabetes and toxins: