Can fast food be part of a weight-loss or healthy diet plan? You might not think so. In fact, you might even think that you can't have a meal that's both quick and healthy.

But this isn't necessarily so. An occasional stop at a fast-food restaurant can fit into a healthy diet plan. The key is to choose wisely.

1. Keep portion sizes small. If the fast-food restaurant offers several sandwich sizes, pick the smallest or order half a sandwich, if available. Bypass hamburgers with two or three beef patties, which can pack more than 1,000 calories and 70 grams of fat. Instead, choose a regular- or children's-sized hamburger, which has about 250 to 300 calories. Also, skip the large serving of french fries or onion rings and ask for a small serving instead. This switch alone saves about 300 calories. Or better yet, select a lower calorie option.
2. Choose a healthier side dish. Take advantage of healthy side dishes offered at many fast-food restaurants. For example, instead of french fries choose a side salad with low-fat dressing or a baked potato. Or add a fruit bowl or a fruit and yogurt option to your meal. Other healthy choices include apple or orange slices, corn on the cob, steamed rice, or baked potato chips.
3. Go for the greens. Choose a large entree salad with grilled chicken, shrimp or garden vegetables with fat-free or low-fat dressing on the side, rather than regular salad dressing, which can have 300 or more calories per packet. Watch out for high-calorie salads, such as those with deep-fried shells or those topped with breaded chicken or other fried toppings. Also, skip salad extras such as cheese, bacon bits, croutons and fried chips, which quickly increase your calorie count.
4. Opt for grilled items. Fried and breaded foods, such as crispy chicken sandwiches and breaded fish fillets, are high in fat and calories. Select grilled or roasted lean meats — such as turkey or chicken breast, lean ham, or lean roast beef.
5. Have it your way. Don't settle for what comes with your sandwich or meal. Ask for healthier options and substitutions. For example, ask for reduced-fat mayonnaise or mustard on your sandwich. Or at a fast-food Mexican restaurant, request salsa with your meal instead of shredded cheese and nacho cheese sauce. Try to avoid special dressings, tartar sauce, sour cream and other high-calorie condiments.
6. Watch what you drink. Many beverages contain a large number of calories. For example, a large soda (32 ounces) has about 400 calories. Instead, order diet soda, water, unsweetened iced tea, sparkling water or mineral water. Also, skip the shakes and other ice-cream drinks, which can contain more than 1,000 calories and all of your saturated fat allotment for the day.

You can eat healthy away from home, even at fast-food restaurants. The bottom line: Be choosy. Make wise menu choices and focus on portion control.