Four days of traveling doesn't sound like much, yet those four days can put a serious dent in your budget and diet if you're eating every meal in a restaurant. Whether you're traveling by car, plane, bus or train, carrying one bag filled with food won't make traveling much more difficult and will save you precious time, money and energy in the long run.

Breakfast

Breakfast is perhaps the easiest meal of the day to pack ahead for, since many breakfast staples don't require refrigeration. A batch of muffins or banana bread frozen until the day of the trip will last all four days. Take a box of instant oatmeal packets, which you can either microwave in your hotel room or boil water to make. Buy a bag of oranges and a bunch of bananas or take along bags of dried fruits. Granola or protein bars are also easy breakfasts for travelers on the go.

Lunch and Dinner

A cooler and the hotel ice machine are key to preserving your lunch and dinner options. Make a few pasta dishes and soups at home, then freeze them and keep them icy in your cooler. Heat them up in your hotel or rental home's microwave oven. When you're camping or have a stove handy, freeze marinated chicken breasts or hamburgers and keep them on ice until mealtime. If you won't have access to heat or ice beyond what you bring from home, make sandwiches with hummus and sliced turkey to keep in the cooler the first day. Once the ice has melted, sandwiches edible at room temperature are your best bet for the last few days of the trip. Pack a few loaves of sliced bread and jars of peanut butter. Slice bananas to add some additional flavor to your sandwich. Take whole red or green peppers to munch on.

Snacks and Drinks

You don't have to worry about keeping snacks cold or hot. Buy packets of nuts, or make your own trail mix by combining nuts, dried fruit and chocolate and peanut butter chips. Take pre-sliced mini bagels or bags of popcorn, chips and pretzels for salty cravings and pieces of fudge or biscotti to satisfy a sweet tooth. Don't cut up fruit in advance unless you're going to eat it right away. Instead, take whole peaches and oranges to wash or peel just before eating. Pack juice boxes, which are delicious even at room temperature, as well as water bottles and juice drink mixes that you can add to water for additional flavor.

Traveling With Food

Most travel-friendly foods work on any type of trip, whether you're flying to a luxury resort or driving to a deserted campsite, but dealing with airport security does make things a bit more difficult. According to the Transportation Security Administration, you can carry frozen food onto a plane as long as it's completely frozen through. Rather than using real ice, you'll have to pack frozen foods with gel-based ice packs. Keep in mind that a bag full of food will count as one carry-on, and most airlines allow only one such item and one personal item like a purse or laptop bag. Try packing non-perishables in your checked bag and carrying frozen foods on in an insulated lunch bag that you can tuck into a larger piece of carry-on luggage. Unless you want to receive dirty looks from fellow passengers, avoid taking strong-smelling foods onto a plane, like anything including seafood. If you're not flying, pack foods into reusable plastic containers to protect delicate items from getting crushed.