A bran muffin can be a healthy snack or a veritable diet-buster, depending on the serving size. Some of the muffins sold in coffee shops and bakeries fall into the "jumbo" category, and they're best avoided if you're watching your weight. If you can't resist the giant treat behind the glass counter, spare your waistline by only eating half and saving the other portion for the next day.
At only 46 calories, a mini bran muffin weighing just 17 grams is a smart snacking choice. A small muffin of 66 grams is also reasonable at 178 calories. Medium, 113-gram muffins contain about 305 calories each, bordering on the size of a small meal. Large, 139-gram muffins have about 375 calories each, while an extra-large muffin of 168 grams will set you back 454 calories. Despite their relatively heavy calorie toll -- and high sugar content -- bran muffins are rich in nutrients such as protein, fiber and iron.
Daily Calorie Recommendations
If you fill most of your diet with low-calorie fare such as fruits and vegetables, bran muffins can fit into your weight-management plan. To maintain your size, Harvard Medical School advises eating 15 calories per pound of body weight: A 135-pound person would maintain a steady weight eating 2,025 calories per day. To lose 1 pound each week, eat 500 fewer calories than you need for weight maintenance each day.