Environmental pollutants may alter the body’s metabolism and predispose some individuals to weight gain.
Sedentary lifestyles and poor diets have long been blamed for people’s inability to lose weight. But growing evidence points to environmental pollutants called “obesogens” that may alter the body’s metabolism and predispose some individuals to weight gain.
“There’s no question that diet and exercise are the major players in the obesity epidemic. But the environment plays a significant role, too,” says Dr. John Molot, a physician at the University of Toronto-affiliated Environmental Health Clinic at Women’s College Hospital in Toronto. “There are many chemicals in the environment that make you gain weight and make it more difficult to lose weight.”
These chemicals are found in many everyday products, including some plastic bottles and containers, liners of metal food cans, detergents, personal care products, flame retardants, food, toys, cosmetics and pesticides, according to the National Institute of Environmental Health Sciences, which has conducted research in this area for three decades.
What are Obesogens?
Obesogens are known as “endocrine disruptors” because they interfere with the chemical messaging of hormones to cells by turning on, shutting off or modifying signals. The endocrine system consists of glands that produce hormones that regulate metabolism, growth and development, and more. Some obesogens affect the number or size of fat cells, while others impact hormones associated with metabolism. Fetal and early life exposure to obesogens may alter fat-cell makeup and metabolism. Adults are at risk, too.
The World Health Organization has identified about 800 chemicals that are known or suspected to be endocrine disruptors, yet only a few have been investigated. The NIEHS has called endocrine disruption “an important public health concern.”
“The research is absolutely exploding in this area. There are many man-made chemicals that affect the receptor sites on cells so they respond differently,” says Margaret Sears, an environmental health researcher associated with the Children’s Hospital of Eastern Ontario Research Institute, the Ottawa Hospital Research Institute and other institutions.
More than one-third of American adults are obese, according to the Centers for Disease Control and Prevention. Obesity has more than doubled in children and quadrupled in teens in the last 30 years. Obesity-related conditions – such as heart disease, stroke, Type 2 diabetes and some cancers – represent the leading causes of preventable death.
Scientists once believed that fat cells primarily stored and released extra energy as needed. “Now we know that fat is a complicated hormone gland that is capable of communicating with other tissues, such as the brain and immune system,” Molot says.
One group of chemicals called persistent organic pollutants is difficult to avoid. “These chemicals don’t break down,” Molot says. “They get into the atmosphere and the water and travel around the world. They get into the food chain and climb up the food chain. They’re found in newborn children because their mothers have been exposed.”
Chemicals like flame retardants found in mattresses, pillows, computers, wall insulation and many other products are obesogens. These chemicals can be inhaled when they adhere to tiny dust particles in the air that can’t be seen.
“Even microwave popcorn bags contain chemicals so they’re less likely to explode,” Sears says.
Although people of all ages are at risk to chemical exposure, children and pregnant women are particularly vulnerable.
“We need to be super concerned about our kids,” Sears says. “There are chemicals that can affect the number of fat cells that your body makes as you’re growing as a child. Although fat cells can get larger or smaller, it’s much more difficult to destroy fat cells when you are older if you created a lot of fat cells as a child.”
Young children who crawl on the floor and put their hands or toys in their mouths are at a higher risk of ingesting flame retardants, stain repellents and other chemicals that land on tiny dust particles. “Although it seems trivial, this hand-to-mouth behavior is a major route of exposure for very young children,” Sears says.
Air pollution is a major risk factor for obesity, too. Polycyclic aromatic hydrocarbons from motor vehicle exhaust, residential heating, oil refining, charbroiled foods and cigarette smoke are obesogens. “One study found that kids with high exposure to these chemicals are more likely to be obese,” Molot says. “Children born to mothers who had higher exposures to these pollutants are more likely to be programmed to become obese.”
Protecting Yourself and Your Family
Although more research is needed to understand the potential adverse health affects of environmental pollutants, people can take steps now to protect themselves and their loved ones.
“There are lots of things you can do to reduce your exposure to these chemicals, save money, simplify your life and save the environment all at the same time,” Sears says. For example:
Choose organic products when possible, and make foods rich in antioxidants (fruits and vegetables) a main part of your diet.
- Avoid eating foods heavily wrapped in plastic. “Plastics don’t last long in the body, but we just keep eating them every day,” Molot says. “So the majority of humans have plastics in them.”
- Beware of canned goods. Some cans are lined with bisphenol-A and bisphenol-S, both considered to be hormone disrupters.
- Avoid scented products – air fresheners, fabric softeners and personal care products – that contain phthalates. “That’s why the smell doesn’t go away,” Sears says.
- Improve the ventilation at home, and work to reduce exposure to toxic chemicals.
- Use natural cleaning products such as vinegar, plain soap and baking soda rather than products loaded with chemicals. “It’s a lot cheaper and it works just as well,” Sears says.
- Clean dust off surfaces, and damp mop the floor often.
- Avoid food with artificial colors and flavors. “Food tastes good and looks good. You don’t need to add this extra stuff to make it a weird color,” Sears says. “It’s done for marketing.”
- Sweating from exercise and sitting in a sauna helps the body get rid of toxins.
While these steps can reduce chemical exposures, experts encourage consumers to call upon policy makers and politicians to address the health implications of environmental pollutants in a more comprehensive and long-lasting manner.
“We need to start proving that chemicals and products are safe first, rather than proving that things are unsafe after [the] fact, as people are being affected,” Sears says.