DIET DETECTIVE: Fact or fiction? Time to debunk culinary myths
Mar 22, 2006
You've heard about mad cow disease, bird flu and E. coli. But how much do you really know about these health scares? Here's the rundown, with expert opinions about real concerns versus hype.
Mad cow disease
What it is: Mad cow disease, or bovine spongiform encephalopathy, is a progressive, degenerative and ultimately fatal disease affecting the central nervous system of adult cattle. The exact cause is unknown, but scientists generally believe it results from infectious forms of a protein called prion, which is normally found in animals.
How you get it: "Humans don't get mad cow disease; the disease in humans is actually a variant form of Creutzfeldt-Jacob Disease," which is believed to be caused by eating beef products from affected cattle, says Dr. Henry Miller of the Hoover Institution at Stanford University. Once contracted, it is fatal.
Why it matters: The disease is scary mostly because it's always lethal. However, experts agree the risk it poses to public health is extremely low. "Very few cattle have been found to be infected," says Caroline Smith DeWaal of the Center for Science in the Public Interest in Washington. "Even in Europe, where many cattle were infected and entered the food supply, only 150 people contracted the human form."
Risk level: Very low.
How to avoid it: Unfortunately, there is no way to cook or prepare meat to eliminate the risk. Patty Lovera of consumer advocacy group Food & Water Watch says some types of beef -- including cuts that contain a bone and products that are ground or made using machines that scrape small bits of meat from large bones are more likely to be contaminated. "Those who are still concerned, despite the extremely low risk, can avoid processed meat products, such as hot dogs, because they are more likely to have nervous system tissue -- but even those foods have minimal risk," says Smith DeWaal.
According to Consumers Union's Eco-labels.org, "organic" and "biodynamic" are the most helpful labels.
Bird flu (from eating fowl)
What it is: Avian influenza, or "bird flu," is a contagious disease caused by viruses that normally infect birds and, less commonly, pigs. However, on rare occasions, avian flu has crossed the species barrier to infect humans. This is particularly true, says Miller, of the highly virulent H5N1 strain, which is spreading rapidly among fowl and which, it is feared, could become a pandemic strain.
How you get it: Humans contract H5N1 from handling infected fowl or their carcasses or from exposure to their secretions or excrement. Direct contact with infected poultry, or surfaces and objects contaminated by their feces, is considered the main route of infection. "There's no evidence that there is a risk of getting the influenza from consumption [of fowl]. People who have gotten sick had close contact with birds, e.g., they are in the chicken coops," says CSPI's Smith DeWaal.
Why it matters: Experts worry because H5N1 avian flu already has two of the three characteristics needed to cause a pandemic: It can jump from birds to humans, and it can produce a severe and often fatal illness. If H5N1 becomes highly transmissible among humans -- the third characteristic of a pandemic strain -- a devastating worldwide outbreak could become a reality.
Risk level: Very low (from eating fowl).
How to avoid it: The World Health Organization confirms that when poultry products are safely handled and properly cooked -- to 180 degrees Fahrenheit -- humans are not at risk of H5N1 through eating. But juices from raw poultry should never touch items eaten raw. Those handling raw poultry should wash their hands thoroughly and clean and disinfect surfaces that have been in contact with the poultry products. Soap and hot water are sufficient.
Nonstick coating on pans
What it is: The biggest concern is the fumes pans emit at high temperatures. They can give humans flu-like symptoms -- called "Teflon toxicosis," says Anne Singer of the Environmental Working Group -- and can kill small birds. At 680 degrees Fahrenheit, nonstick pans release at least six toxic gases, including two carcinogens and MFA, a chemical lethal to humans at low doses. However, Teflon toxicosis is not necessarily caused by the perfluorooctanoic acid, or PFOA, used in the manufacturing of Teflon coating. That acid, the EPA says, potentially causes cancer in rats.
How you get it: Teflon toxicosis occurs when Teflon and other nonstick surfaces are heated to temperatures at which the coating breaks apart and emits toxic particles and gases. This breakdown has been linked to hundreds, perhaps thousands, of pet bird deaths and an unknown number of human illnesses each year. As far as PFOA is concerned, it is not actually in Teflon coatings; they are a relatively minor source of exposure to PFOA. PFOA reaches our bodies because of the millions of consumer products containing PFOA that fill our homes, work and outdoor environments (waterproof clothing, stain-proof carpeting, leakproof food packaging).
Why it matters: Teflon toxicosis hurts birds and can create unhealthy symptoms in humans. According to the Environmental Working Group, PFOA is estimated to be in the blood of 96 percent of all Americans. Potential issues involve liver function, blood counts, prostate cancer, leukemia or multiple myeloma.
How to avoid it: Avoid overheating your pans.
Risk level: Very high for pet birds; unknown for humans.