No, that pastrami from 2009 is not OK

The holiday feasting is over, but plenty of food still remains in most people s kitchens. Yet before you tuck into the leftovers, a little caution is in order: According to the Centers for Disease Control and Prevention, about one in six Americans fall ill every year because of something we ve eaten. In the post-holiday spirit of prevention, The Wall Street Journal s Katherine Hobson spoke with microbial hygiene expert Dr. Elizabeth Scott, of Simmons College Center for Hygiene and Health in Home and Community, on the subject of bacterial contamination.

First of all, Dr. Scott says, make sure your food is prepared correctly separate raw meat from other ingredients and cook all ingredients to a proper temperature. Once the meal has been cooked, it s best to refrigerate it within two hours, making sure to separate larger quantities into shallow, covered containers in order for the food to cool quickly.

And make sure not to let those leftovers languish in the back of the fridge! Dr. Scott recommends eating the remaining food within three days, given that cool temperatures typically won t kill bacteria they just slow their growth. And, says Dr. Scott, try to avoid repeated reheatings; it s safest to reheat the food just once, to an internal temperature of 160 degrees.

Dr. Scott s advice gets the thumbs up from ACSH s resident nutrition expert, Dr. Ruth Kava. We also recommend that, for further information, you take a look at our publication that s all about Avoiding Foodborne Illness.

ACSH s Dr. Josh Bloom also reminds us that some bacteria, particularly staph, produce toxins that are impervious to heat. So even if you cook an already-spoiled food thoroughly and kill the bacteria, the toxin will still make you ill. The key, he says, is not to let the food spoil in the first place.