Tuna
This fish is a high-quality protein, low-fat and packed with heart-healthy omega-3 fatty acids. But watch out how much you eat – it’s responsible for 40% of all mercury intake from seafood. And that's not good news.Mercury affects brain function and development, says Sonya Lunder, a senior analyst with the Environmental Working Group (EWG). In fact, the Food and Drug Administration (FDA) advises women who may become pregnant, or are carrying or nursing, to avoid or cut back on tuna.
Wise up: If you’re eating fresh fish, a safer choice is wild salmon. Other low-mercury options include tilapia, shrimp and trout. (Check the Monterey Bay Aquarium’s Super Green List naming fish that meet food safety requirements, having the least amount of toxins while also being sustainable fish.)
And look at size. In general, “the smaller the fish, the less the toxic burden,” says Jeannie Gazzaniga-Moloo, Ph.D., a registered dietitian and spokeswoman for the American Dietetic Association (ADA).
Soy
Tofu, edamame and other soy products are a good source of vegetable protein. But they also have phytoestrogens.In high doses, they can produce estrogen-like effects and potentially raise the risk of some breast cancers, according to the American Cancer Society (ACS).
Wise up: Moderate amounts – no more than 3 servings per day – doesn’t produce dangerous effects if you ingest this food, according to the ACS. But talk to your physician about whether soy is right for you, based on your personal and family history of breast cancer.
Peaches
This sweet treat, full of potassium and other nutrients, is at the top of EWG’s Dirty Dozen, a list of foods with the highest levels of pesticides. Bugs love them, so farmers spray crops more.Insect repellents can cause health problems, such as birth defects, nerve damage and cancer, depending on the toxicity and amount consumed, according to the Environmental Protection Agency (EPA).
Even safer: Avoid them and eat thick-skinned fruits that you peel, such as oranges, mangoes, watermelon and grapefruit.
Spinach and lettuce
Leafy greens are excellent sources of vitamins K and C. But because they grow low to the ground and are soft and succulent, they attract bugs. So farmers use more pesticides, says Lunder.They’re also easily contaminated with bacteria such as E. coli, which can cause serious gastrointestinal troubles, even death. A Consumer Reports study found that nearly 40% of pre-washed salads – lettuce and spinach – may contain potentially harmful bacteria.
Wise up: Go organic and always thoroughly wash spinach and lettuce, even if it’s labeled pre-washed.
Kill E. coli by boiling the greens at 160˚ for 15 seconds, according to the Centers for Disease Control and Prevention (CDC).
Strawberries
These berries are rich in vitamin C but also “have the highest amount of pesticide residue of any berry,” Lunder says.Like greens, low-growing strawberries are easy for pests to infest. The fruit’s soft, seed-filled skin also makes food safety more difficult to maintain because it's harder to remove pesticide residue.
Watch out for bad berries too. Because they’re sold in baskets, moldy strawberries can contaminate the whole bunch. Most molds are harmless, but some contain harmful bacteria, including E. coli.
Wise up: Go organic – healthy foods are worth the expense. Before you buy, check for the mold.
At home, rinse strawberries under running water and cut out bruised or damaged areas where bacteria can thrive, advises Gazzaniga-Moloo.
Beef
Beef, a good but fatty protein source, contains traces of antibiotics that are used to prevent or treat diseases in feed cattle. Farm animals get about 70% of the antibiotics used in the U.S. annually, according to the Union of Concerned Scientists.Wise up: Look for beef labeled “organic” or “natural." It means the meat is free from growth hormones and antibiotics, and that the animal consumed organic feed.
Alfalfa sprouts
Sprouts have been a health food staple since the ’60s for good reason: They have disease-fighting phytochemicals.But they’re also a bacterial breeding ground because they’re grown in a watery, warm environment. Raw sprouts have been linked to salmonella and E. coli contamination.
Wise up: Avoid the food completely, especially pregnant women and children, the FDA and CDC advise.
You can’t make them safe: Sprouts are difficult to wash thoroughly because of their bundled shape, and cooking these delicate seedlings destroys them.
Microwave popcorn
Fiber-rich popcorn isn’t the problem. It’s the way it’s packaged: The inside of microwave popcorn bags is lined with a Teflon-like chemical, fluorooctanoic acid, which can contaminate kernels.Researchers are studying whether the acid causes cancer but have yet to find conclusive evidence, says Lunder.
Wise up: Pop it on your stovetop for ultimate food safety precaution – or make your own microwave-safe bags!
Place a quarter-cup of popcorn kernels in a brown-paper lunch bag, add a teaspoon of olive oil and staple it closed. Heat in the microwave for 2 minutes. To prevent burning, stop it earlier if the delay between pops is more than 2 seconds.
Canned food
Canned vegetables, fruits and meats are convenient for busy moms. But there’s a price: Nearly all are lined with BPA (bisphenol A), a hormone-disrupter that’s used to harden plastics.BPA can leach into food and our bodies, where it mimics estrogen and has been linked to birth defects and an increased risk of diabetes. The worst BPA offenders are chicken soup, ravioli and infant formula, according to the EWG tests. It turns healthy foods into unsafe foods.
Wise up: Rinsing canned fruits and vegetables may reduce BPA, but it’s safer to switch to frozen foods and eat fresh when possible.
Children and pregnant women should limit consumption of these foods. Also, use powdered baby formula, which may not have BPA in packaging and is more diluted with water.