We’re going on vacation next month, and I don’t know how I’m going to keep our diets on a healthy track. Do you have any suggestions?

In the sports world, there’s a phenomenon known as the “home court advantage.” From the field to the locker room to the dining room, the team’s home town is better set up for them than any other city. For most people, even those who pay little attention to their diet, the food at home will have less fat, salt, and preservatives than you’ll find in most restaurants.

If you want the dominant memory of your vacation to be that the children were sick a good deal of the time, just allow them to eat potato chips and soft drinks in the car. Feed them from fast food restaurants, and use a candy bar to fill in the between-meal munchies.

If you’re traveling by car, pack healthy snacks. Fruit, cutup vegetables, cold pasta, and slices of multigrain bread can all be packed and put in the car. Add several small, plastic bottles of water for refreshment. If you put the bottles in the freezer overnight before you leave, the water will melt slowly and remain cool for several hours. Take a paring knife and some unbreakable containers with you, and you can stop at grocery stores along the way and replenish your supply of most things.

If we’re traveling by plane, we also bring a few sandwich bags with munchies so our daughter doesn’t get fretful waiting for a meal. We usually bring a quart of mineral water along in case the flight attendant isn’t serving when our daughter is thirsty.

Vacationing in a foreign country presents some special challenges. Whether you’re going to Mexico, South America, Asia, Africa, or Europe, you’re going to find bacteria and viruses that the locals can tolerate but you and your family can’t. Especially when you leave the major cities, you must be very careful about what you eat and drink in order to avoid getting very sick. Fruit and vegetables need, at least, to be washed and, probably better, also peeled. Some countries require inoculations before you are allowed to visit. I have had people tell me they’ve traveled with supplies of antibiotics and over-the-counter stomach remedies. These medicines don’t do much good.

The important thing to watch if your children do get sick is their water intake. A young child who is vomiting or has diarrhea can become dangerously dehydrated very quickly. If the symptoms don’t go away within a day or if the child runs a fever, consult a doctor immediately, even if you must use sign language to be understood.

With a little care and preplanning, your vacation will be as much fun as you had hoped.