Mustard is actually a good condiment to use because its mustard powder and vinegar. However, I have to agree with the individual who told you that eating sandwiches aren't a good ideawhen losing weight. Especially if you are using white bread, not whole wheat or multigrain. The thing is when trying to lose weight I have been told by my physician that limiting yourself to one carb per meal is recommended. Two slices of bread equal two carbs. So if you really mush have the sandwich cut it in half, and have something else such as a side salad, raw vegetables, no potato chips though once again a carb. b