Protein and fat: a happy couple

Whether you're cobbling together a series of minimeals between taxis and airport stops, or having a long leisurely lunch on the train, build your repast with the protein-carbohydrate-fat triad. Protein and fat take longer to digest, providing you with extra staying power, while carbohydrates provide much-needed energy to prolong your travel stamina. Keep in mind that sitting on a train or car or on an airplane demands much less energy than your daily work-a-day activities, so listen to your body's needs and eat only when hungry.

• At home, prep bite-sized hunks of cheese, hard-boiled eggs, and edamame (cooked soybeans)
• Buy ready-made single-serving yogurts, protein-rich energy bars, and packs of nuts and seeds

Pack perishables in a small cooler.

Carb(s)-not a four-letter word

Your journey won't be complete without a carry-on of carbs. "Carbohydrates," says Elson Haas, MD, author of Staying Healthy with Nutrition, "are a quick source of energy for the body, easily converted to glucose, the fuel for the body's cells." Make your carbohydrates complex (not refined) by choosing whole-grain pretzels, crackers, cereal, and tortillas, and whole fruits and vegetables.

For fiber, vitamins, and minerals, as well as color for your menu, fruits and vegetables make ideal travel mates.

• Pack fruits that don't bruise easily, such as apples, grapes, pears, and cherry tomatoes
• Dried fruit-raisins, apricots, pineapple, mangoes, papaya, and so on-pack a punch with minerals and fiber
• Tuck into an assortment of sugar snap peas, cucumber spears, and carrot and celery sticks with a side order of salad dressing, hummus, or black bean dip for an abundance of antioxidants, fiber, and vitamins
• For a treat, make your own trail mix with nuts, seeds, dried apples, raisins, dates, chocolate or carob chips, and low-sugar, high-fiber cereal

This trove will come in handy if you find yourself out of food and in the midst of a long layover at the airport or at the tail end of a long drive.

Hydrate, hydrate, hydrate

Drink lots of water before you embark on your journey and by avoiding alcohol and caffeinated beverages while en route. Make water a constant travel companion or sip decaffeinated teas or fruit juice mixed with bubbly water.