If you cut just 100 calories a day, you could lose a pound a month—as many as 12 pounds in a year. But where do those 100 calories come from, and how can you eliminate them from your diet? Here, we show you how.

Those one or two slices you devour before your meal can pack on an extra 60 to 200 calories.

While most mayo brands pack 100 calories into just one tablespoon, the average serving of mustard contains only three.

Split a piece of cheesecake with a friend. Eating half instead of a whole piece could save you up to 150 calories and 10 grams of fat (not to mention a few dollars, too).

Drink water instead. Or, for a refreshing twist, try seltzer with lemon or lime.

Enjoying a serving of roasted chicken instead of fried chicken can save you as much as 150 calories in one meal.

You don't even have to skip the fries altogether. Simply downsizing to a medium instead of a large will save you up to 188 calories.

Substituting some portabella mushrooms for a couple ounces of beef will reduce your calorie intake by over 100.

When ordering a cup of morning joe, do you get whipped cream on top? Next time, say no, and you'll cut 100 calories before you even start your day.

Eating two slices of thin crust pizza instead of thick pan pizza could save you about 160 calories. Skipping the pepperoni on those two pieces will eliminate another 80

If you like tuna fish, one of the simplest swaps you can make is to eat tuna packed in water instead of tuna packed in oil. This will save you about 140 calories.