Americans enjoy one of the safest, most healthful food supplies in the world. But a lot has changed in the last few decades—from the way food is produced and distributed to the way it is prepared and eaten. Years ago, food was produced close to where we lived. People shopped daily, preparing and eating their food at home. Dining in restaurants was saved for special occasions. But today, food in your local grocery store comes from all over the world, and nearly 50 percent of the money we spend on it goes to buy food that others prepare, like “carry out” and restaurant meals.

Currently, we are more knowledgeable about illnesses that can be caused by harmful bacteria in food. What we used to call “stomach flu,” we now know that most of the time, it is really “food poisoning” or foodborne illness. In addition, we realize that some illnesses can be traced to foodborne illness, and that some people are more likely to get sick from this than others. The people most at risk are: pregnant women, young children, older people, and those with chronic illnesses, thus weakened immune systems.

Usually foodborne bacteria take one to three days to cause illness. But you can become sick anytime from 20 minutes to six weeks after eating foods containing dangerous bacteria. It depends on a variety of factors, including the type of bacteria in the food. The symptoms are commonly: vomiting, diarrhea or bloody diarrhea, abdominal pain, fever and chills.

One of the complications of foodborne illnesses is dehydration, caused by fluids lost through vomiting and diarrhea. When dehydrated, the body lacks enough fluid and electrolytes (ionic solutions or salts existing in nature in the form of minerals such as sodium, potassium and chloride) to function properly, especially to people at risk. Signs of dehydration are excessive thirst, infrequent urination, dark-colored urine, lethargy, dizziness or faintness. In infants and young children, signs are dry mouth and tongue, lack of tears when crying, no wet diapers for 3 hours or more, high fever, unusually cranky or drowsy behavior, and sunken eyes, cheeks, or soft spot in the skull. Also, when people are dehydrated, their skin does not flatten back to normal right away after being gently pinched and released. Seek medical help in this scenario.

Although foodborne illness can be dangerous, it is often easy to prevent. By following the basic rules of food safety, you can help prevent this illness for yourself and others. Rinse raw produce in water, but don’t use detergents; a vegetable brush may be appropriate. It may be important to reheat some foods that you buy pre-cooked, because they can become contaminated with bacteria after they have been processed and packaged at the plant. These foods include hot dogs, luncheon meats, cold cuts, dry sausage, and other deli-style meat and poultry products.

Using sponges is a bad practice in the kitchen. Bacteria can easily hide in the holes of the sponge and can cause serious problems of cross contamination, such as cleaning up from raw meat or poultry, then using the cutting surface that you wiped for fresh vegetables. The best idea is to avoid sponges altogether.

Eating out at a restaurant can be safe and enjoyable but look at how clean things are before you even sit down. If it’s not up to your standards, you might want to eat somewhere else. All food service establishments are required to follow food safety guidelines set by state and local health departments. But you can also take actions to ensure your foods’ safety.

No matter where you eat out, always order your food cooked thoroughly to a safe internal temperature. Remember that foods like meat, poultry, fish and eggs need to be cooked thoroughly to kill harmful bacteria. When you order a hot meal, make sure it’s served to you piping hot and thoroughly cooked, and if it’s not, send it back.

Don’t eat undercooked or raw foods such as eggs; they can be a hidden hazard in some foods like Caesar salad, custards and some sauces. If these foods are made with commercially pasteurized eggs (including egg substitutes, which are pasteurized), they are safe. The Department of Health in some states is asking restaurants to now use irradiated ground beef and pasteurized eggs.

Meal portions are getting larger these days, and many times people pack up those leftovers to eat later. But if you will not be arriving home within two hours, it is safer to leave the leftovers at the restaurant. The inside of a car can get very warm, and bacteria may grow rapidly, so it is always safer to go directly home after eating and put your leftovers in the refrigerator.

The single most important step you can take to prevent the spread of infection is washing your hands. And the old adage, “when in doubt throw it out” remains as sound advice.