Environment and Diet are Factors in Rising Adult-Onset Diabetes

From: Robina Suwol
Date: 25 Oct 2002
Time: 23:21:16
Remote Name:


Thursday, October 24, 2002
By Melissa Knopper, E/The Environmental Magazine

Seventeen million Americans have diabetes, and the incidence of new cases has increased 32 percent since 1990, according to the U.S. Centers for Disease Control and Prevention. People are being diagnosed at younger and younger ages, and experts are still searching for the cause, but most say it is related to high-fat diets and a lack of exercise. "It's really mirroring the increasing trend of obesity," said Dr. Francine Kaufman, president of the American Diabetes Association.

Many scientists believe diets heavy in highly refined carbohydrates and environmental factors also play a significant role. In the past, researchers have considered everything from zinc and arsenic in drinking water to viruses and cows' milk. But dioxin exposure may be the most significant environmental risk factor related to adult-onset, or Type II, diabetes. Dioxin is a chemical byproduct of industrial processes that use chlorine, from plastic manufacturing and paper bleaching to waste incineration. It accumulates in fatty tissue and causes a variety of health problems, even at very low levels of exposure. Dioxin is known as an endocrine disrupter, and diabetes is a disease of the endocrine system.

AN AGENT NAMED ORANGE The most intensive studies of diabetes and dioxin focus on Operation Ranch Hand, a group of 1,000 Air Force veterans who sprayed the dioxin-laced herbicide Agent Orange during Vietnam. When scientists compared a group of Ranch Hand veterans to a control group, they found the Ranch Hand veterans with the highest exposures were 50 percent more likely to develop adult-onset diabetes. Between 1962 and 1971, Operation Ranch Hand soldiers used more than 11 million gallons of Agent Orange to destroy forested areas Viet Cong guerrillas used for cover. Vietnam veteran Rick Weidman said he was exposed to Agent Orange, along with a toxic cocktail of other herbicides known as Agent Blue, Agent White, Agent Purple, and Agent Pink. "I was a medic, and we sprayed it from backpacks," Weidman said. "It got on your hands, soaked into your clothes, and the dust blew it into your mouth, so you were essentially eating it."

Weidman, who now suffers from a degenerative eye disease and a mysterious condition that causes hair loss on his legs, said nobody in the field knew Agent Orange had dioxin in it. "No safety precautions were taken," he added. A report published by the National Academy of Sciences' Institute of Medicine, "Veterans and Agent Orange: Update 2000," offered new information that strengthened the case for a link between diabetes and dioxin, said David Strogatz, an epidemiologist with the State University of New York at Albany who helped write the document. For example, some of the original studies continued to show a stronger association over time, even after scientists adjusted them for other factors, such as obesity, that could also cause diabetes, he explained.

The Institute of Medicine report prompted the Department of Veterans Affairs (VA) to offer special compensation payments to veterans who believe they developed diabetes because they were exposed to Agent Orange. The department estimates that 9 percent of the nation's Vietnam veterans (about 200,000 people) qualify for the payments because they have diabetes. But Weidman, director of government relations for the Washington, D.C.­based Vietnam Veterans of America, wonders if the diabetic veterans who qualify will actually get the help they need. "The VA has done practically no outreach on this," he said.

In a related study of dioxin and diabetes, Matthew Longnecker of the National Institutes of Health showed a connection between dioxin exposure and diabetes in Vietnam veterans who did not work directly with Agent Orange. "He found those with higher background levels of dioxin contamination had a greater risk for diabetes," said Dr. Arnold Schecter, professor of environmental sciences at the University of Texas School of Public Health. BACKGROUND DIOXIN It's still unclear whether the background levels of dioxin we encounter in everyday life could be contributing to the rising number of diabetes cases, experts say. But Schecter said it makes sense to reduce your personal dioxin exposure just in case.

The U.S. Environmental Protection Agency (EPA) estimates we absorb a background level of approximately five parts per trillion of dioxin in our bodies from the air, water, and food. High-fat meats, fish, and dairy products are laden with the most dioxin, Schecter said, so it's best to cut back on those first. Substitute low-fat frozen yogurt for ice cream and go for grilled chicken instead of a cheeseburger, he suggested. Also, adding more fruits and vegetables to your diet makes sense. Schecter studied a group of 30-year vegans and found they had extremely low levels of dioxin in their blood. Under this low-fat dioxin elimination plan, it takes three to 11 years to cut the amount of the chemical in your system in half, Schecter said.

The real solution is to prevent factories from dumping dioxin into the environment in the first place, says activist Monica Rohde, director of the Stop Dioxin Campaign for the Falls Church, Va.­based Center for Health, Environment, and Justice. So far, industry executives have been arguing the science doesn't prove dioxin is a health threat, Rohde said. "The Vietnam veterans' exposure to Agent Orange has been an important case study to show there's a link," she added. The center is lobbying the EPA to release its dioxin reassessment report, which will officially spell out health risks. "We're saying we know enough: Let's keep studying it, but let's also start acting and put some policy in place so we can reduce the level of dioxin that is accumulating in people with each new generation," Rohde said. REDEFINING YOUR DIET When it comes to diabetes, however, fast food and too much television can be more toxic than dioxin, said Dr. Rich Jackson, senior investigator at Harvard University's Joslin Diabetes Center.

While sometimes genetics can work against you, the best way to avoid developing diabetes is to eat right and exercise more. In one study, Jackson found that walking 20 minutes per day helped subjects lose 7 percent of their body weight and reduce their incidence of diabetes by 50 percent. "Those lifestyle changes can be very powerful," Jackson said. The magazine Taste for Life wrote last year, "Although adult-onset diabetes tends to run in families, it can't develop without a steady supply of carbohydrates." The publication pointed out that people are eating large amounts of concentrated sugars for the first time in history, and it proposed a possible link between diabetes and "the modern American diet of highly processed snacks, white bread, refined pasta, sweetened cereals, and candy bars, which cause abnormal elevations of blood glucose."

Taste for Life advises consumers to minimize such processed foods and also to limit soft drinks and the intake of partially hydrogenated vegetable oils (including corn and safflower oils). In contrast, a diet rich in whole fruits and vegetables provides many vitamins and minerals that may help prevent onset diabetes. Specifically, alpha-lipoic acid, vitamin C, and trivalent chromium (as in the common forms chromium polynicotinate and chromium picolinate) are thought to be preventative. Some research even shows that simple sugars may cause bodies to lose beneficial chromium. The herbs milk thistle seed, American ginseng, and dandelion root may also help keep blood sugar levels in balance, according to Taste for Life.

Melissa Knopper is a Denver-based freelance science writer.
Copyright 2002, E/The Environmental Magazine All Rights Reserved

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