When you really need to go organic … … and when plain "conventional" will do. Use this guide to make the best picks for your health

Shape, Sept, 2006 by Holly St. Lifer

In the dairy and egg case

Conventional dairy farms in the United States raise cows using hormones so they'll grow faster and produce more milk. The European government has banned the use of these hormones based on early research suggesting they may cause early puberty in girls, and raise the risk of breast cancer in women and prostate cancer in men.

Antibiotics are also given to cows and chickens to keep them from getting sick. Many consumers believe that they will ingest a dose of these drugs through food, but that's incorrect, say experts. Antibiotics are strictly regulated so the meat, dairy and eggs you buy don't contain any residue. Instead, scientists worry that overuse of the drugs in animals will raise the incidence of antibiotic-resistant infections in human beings.

* Go organic when buying milk, cheese and yogurt. You'll eliminate the potential risk caused by hormones. Plus, a recent Danish study found that organic milk contains more vitamin E, beta carotene and antioxidants than conventional kinds.

* Save on eggs. Organic chickens are given pesticide-free feed, so farmers say their eggs contain fewer chemicals too. But the amount of pesticides in a conventional egg is minimal in any case.

In the meat and poultry aisle

The reasons you'd pick organic meat are the same ones for milk and cheese: hormones and antibiotics.

* Go organic when you're making beef or lamb for supper. The hormones given to dairy cows are also used in sheep. And organic processed meats, like cold cuts, sausage and bacon, don't contain the preservatives, nitrites or nitrates, which have been linked to brain and bladder cancer.

* Save on pork and poultry. Pigs and chickens are never given any hormones under the conventional USDA guidelines.

In the seafood case

Unlike with produce and meats, the USDA has not set standards for organic claims on seafood, yet many suppliers still use the term. Because of this, California has banned the word "organic" when used with seafood, saying it's misleading for consumers. Although some fisheries insist they use organic feed, their fish and shellfish may still contain contaminants found in water, like mercury and harmful chemicals like PCBs and dioxins.

* Save on all organic seafood. A smarter idea: Base your decision on which species contain the least amount of mercury. Larger species, like swordfish and tuna, have higher levels of the heavy metal than smaller ones, such as shrimp, tilapia and whiting. (For a full list, go to cfsan.fda.gov.) Another tip: Opt for wild seafood. One study published in the journal Science found that farmed salmon has 10 times as many toxins as those raised in the wild.

In the frozen foods section and canned food aisle

Read nutrition labels first when making your pick. Then, follow the recommendations for going organic in each of the food categories above.

* Go organic when purchasing frozen/canned fruits or vegetables that belong to the "dirty dozen" list (the fruits and vegetables that are highest in pesticides). Also consider organic entrees, sauces and soups in which the main ingredients may contain pesticide or hormone residues, such as with beef, lamb, milk and whole-wheat grains.