7 Foods That Should Never Cross Your Lips

What the toxicologist won't eat: microwave popcorn

Olga Naidenko, Ph.D., is a senior scientist for the Environmental Working Group.

The problem: Chemicals, including perfluorooctanoic acid (PFOA), in the lining of the bag, are part of a class of compounds that may be linked to infertility in humans, according to a recent study from UCLA. In animal testing, the chemicals cause liver, testicular and pancreatic cancer. Studies show that microwaving causes the chemicals to vaporize—and migrate into your popcorn. "They stay in your body for years and accumulate there," says Naidenko, which is why researchers worry that levels in humans could approach the amounts causing cancers in laboratory animals. DuPont and other manufacturers have promised to phase out PFOA by 2015 under a voluntary EPA plan, but millions of bags of popcorn will be sold between now and then.

The solution: Pop natural kernels the old-fashioned way—in a skillet. For flavorings, you can add real butter or dried seasonings, such as dillweed, vegetable flakes, or soup mix.

Budget tip: Popping your own popcorn is dirt cheap.

What the farm director won't eat: nonorganic potatoes

Jeffrey Moyer is the chair of the National Organic Standards Board.

The problem: Root vegetables absorb herbicides, pesticides, and fungicides that wind up in soil. In the case of potatoes—the nation's most popular vegetable—they're treated with fungicides during the growing season, then sprayed with herbicides to kill off the fibrous vines before harvesting. After they're dug up, the potatoes are treated yet again to prevent them from sprouting. "Try this experiment: Buy a conventional potato in a store, and try to get it to sprout. It won't," says Moyer, who is also farm director of the Rodale Institute (also owned by Rodale Inc., the publisher of Prevention). "I've talked with potato growers who say point-blank they would never eat the potatoes they sell. They have separate plots where they grow potatoes for themselves without all the chemicals."

The solution: Buy organic potatoes. Washing isn't good enough if you're trying to remove chemicals that have been absorbed into the flesh.

Budget tip: Organic potatoes are only $1 to $2 a pound, slightly more expensive than conventional spuds.

Potatoes get a bad rap as carbohydrates. But see why eating carbs can help you slim down—and how to do it right.

What the fisheries expert won't eat: farmed salmon

David Carpenter, M.D., director of the Institute for Health and the Environment at the University at Albany, published a major study in the journal Science on contamination in fish.

The problem: Nature didn't intend for salmon to be crammed into pens and fed soy, poultry litter and hydrolyzed chicken feathers. As a result, farmed salmon is lower in vitamin D and higher in contaminants, including carcinogens, PCBs, brominated flame retardants, and pesticides such as dioxin and DDT. According to Carpenter, the most contaminated fish come from Northern Europe, which can be found on American menus. "You could eat one of these salmon dinners every five months without increasing your risk of cancer," says Carpenter, whose 2004 fish contamination study got broad media attention. "It's that bad." Preliminary science has also linked DDT to diabetes and obesity, but some nutritionists believe the benefits of omega-3s outweigh the risks. There is also concern about the high level of antibiotics and pesticides used to treat these fish. When you eat farmed salmon, you get dosed with the same drugs and chemicals.

The solution: Switch to wild-caught Alaska salmon. If the package says fresh Atlantic, it's farmed. There are no commercial fisheries left for wild Atlantic salmon.

Budget tip: Canned salmon, almost exclusively from wild catch, can be found for as little as $3 a can.

Could eating fish help boost your flu immunity?

What the cancer researcher won't drink: milk produced with artificial hormones

Rick North is project director of the Campaign for Safe Food at the Oregon Physicians for Social Responsibility and former CEO of the Oregon division of the American Cancer Society.

The problem: Milk producers treat their dairy cattle with recombinant bovine growth hormone (rBGH or rBST, as it is also known) to boost milk production. But rBGH also increases udder infections and even pus in the milk. It also leads to higher levels of a hormone called insulin-like growth factor in milk. In people, high levels of IGF-1 may contribute to breast, prostate and colon cancers. "When the government approved rBGH, it was thought that IGF-1 from milk would be broken down in the human digestive tract," says North. As it turns out, the casein in milk protects most of it, according to several independent studies. "There's not 100 percent proof that this is increasing cancer in humans," admits North. "However, it's banned in most industrialized countries."

The solution: Check labels for rBGH-free, rBST-free, produced without artificial hormones or organic milk. These phrases indicate rBGH-free products.

Budget tip: Try Wal-Mart's Great Value label, which does not use rBGH.

The organic-foods expert won't eat: conventional apples

Mark Kastel, a former executive for agribusiness, is codirector of the Cornucopia Institute, a farm-policy research group that supports organic foods.

The problem: If fall fruits held a "most doused in pesticides contest," apples would win. Why? They are individually grafted (descended from a single tree) so that each variety maintains its distinctive flavor. As such, apples don't develop resistance to pests and are sprayed frequently. The industry maintains that these residues are not harmful. But Kastel counters that it's just common sense to minimize exposure by avoiding the most doused produce, like apples. "Farm workers have higher rates of many cancers," he says. And increasing numbers of studies are starting to link a higher body burden of pesticides (from all sources) with Parkinson's disease.

The solution: Buy organic apples.

Budget tip: If you can't afford organic, be sure to wash and peel them. But Kastel personally refuses to compromise. "I would rather see the trade-off being that I don't buy that expensive electronic gadget," he says. "Just a few of these decisions will accommodate an organic diet for a family."

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