Manners can be helpful if you're trying to make a decent impression on a date, at a business meeting or on any social occasion — they might even help keep a marriage together. However, there is an even better reason to eat with etiquette: It can help you lose weight. Here are a few table manners that will help you look better in two ways — your waistline and your eating style.

Don't talk with your mouth full: Take a peek around the next time you're at a restaurant — most people have forgotten this classic rule. "No one likes to see a mouth stuffed full of food — especially if the mouth is also attempting to talk. Put down your utensils occasionally and direct your attention to the conversation," says Robin Abrahams, the Boston Globe's manners expert.

"Not only will this remind your dining partners that the food is but an excuse for their company — not the other way around — but it will give your body a break in which it can tell you, 'We've had enough, thanks,' " says Abrahams. When you eat with your mouth closed you typically take smaller bites, so you probably will not eat as much.

Smaller is better: According to Susan Fox, the founder of Etiquette Survival and author of "Etiquette for Dummies," don't put more on your plate than you can eat. Overeating is bad for your health, and it isn't polite to overload your plate. Keep portions small; you can always take more later, says Fox.

Be formal: Always prepare a nice table for dinner — from tablecloth to wine glasses — even if you're eating alone, says Michele Wilson, creator of the "Manners by Michele" DVDs. Play smooth music to add to the ambiance and dress up. This may seem over the top — but it works.

Keep it straight: "Pay attention to your posture and body language. During the meal, keep both feet flat on the floor or cross your feet at the ankles. Don't cross your legs at the knees, and don't prop your feet on chair rungs or table legs," says Fox. She also recommends sitting up straight on the front three-quarters of your chairs so you don't bend over your food.

Stay balanced: According to Fox, you should keep pace with others at the table; do not eat too slowly or too quickly. "Everyone should be doing the same thing about the same time," says Fox.

"If everyone else wants dessert, order a cup of decaf or herbal tea so that they'll feel you're keeping them company. If you order only an appetizer or salad, make sure it's brought out with the dinner," says Abrahams.

Stick to your own plate: Not only is it bad manners to reach across the table and pick a morsel off your dining companion's plate, but also, those little "tastes" can add up to a lot of extra calories.

Don't dip: Fox advises against dipping, dunking or wiping sauces with your bread. The only time dipping is acceptable is if there's a dish of olive oil on the table or if you're eating fondue.

Charles Stuart Platkin is a nutrition and public-health advocate, and author of "Breaking the FAT Pattern" (Plume, 2006). Sign up for the free Diet Detective newsletter at www.dietdetective.com.