Whether you’re looking at the nutrition info on a box of pasta, choosing from a fast-casual restaurant's menu or checking your fitness tracker's stats, calorie counts are everywhere. What do these numbers really mean? And how can you use them to improve your health?
To start, you should understand the term “calorie.” A calorie is a measurement of the amount of energy that’s released when your body digests food. Foods with higher amounts of calories can provide more energy. But if you take in too many calories, your body stores the extra amount as fat. The foods you eat contain different amounts of calories. Here’s how the macronutrients break down:
- Fats: 9 calories per gram
- Proteins: 4 calories per gram
- Carbohydrates: 4 calories per gram
How do you know how many calories you need?
In the Dietary Guidelines for Americans, you’ll find estimates. Depending on age and activity level:
- Adult men need 2,200 to 3,000 calories per day
- Adult women need 1,600 to 2,400 calories per day
You can also use free online calculators, such as the Body Weight Planner by the National Institutes of Health (NIH), where you can calculate your needs based on your height, sex, age, current weight and activity level. “Be sure you are choosing accredited sites like the NIH if you are using an online calculator,” said Lauren Turilli, a registered dietitian at Banner Health in Mesa, AZ.
What can change the number of calories you need?
A lot of factors play into how many calories you should take in:
- Age: You need fewer calories as you get older.
- Gender: Men generally need more calories than women.
- Height: Taller people need more calories than shorter people.
- Weight: People who are more muscular or heavier need more calories than lighter people (though if you want to lose weight, you may need fewer calories).
- Activity level: If you exercise regularly or have a physically demanding job, you’ll need more calories than someone who is sedentary.
- Pregnancy or lactation: You need more calories if you are pregnant or breastfeeding.
How should you adjust your caloric intake based on your goals?
Your body weight and your calorie intake are closely linked. So, you may want to change the number of calories you eat based on whether you want to maintain, gain or lose weight. To lose weight, you need to eat fewer calories than your body burns each day. Conversely, to gain weight, you need to consume more calories than you expend.
“But keep in mind that while the ‘calories in vs. calories out’ concept of weight loss may seem simple, there are a lot of factors that contribute to weight loss or the inability to lose weight, including medical diagnoses, hormonal changes, genetics and age,” Turilli said.
If you would like guidelines for changing or maintaining your body weight, you can enter your goal weight and the timeframe in which you would like to reach that goal or the weight you want to maintain, into the NIH Body Weight Planner. It will recommend a number of calories for you to eat per day.
If you want to lose weight, it’s essential that you only scale back your calories moderately. You might be tempted to eat a lot less, thinking you’ll lose weight faster. But cutting your calories too drastically is a bad idea—it can cause serious side effects and increase your risk of nutritional deficiencies.
“Many fad diets recommend restricting your calorie intake to around 1,000 to 1,200 calories per day, which is not enough for most healthy adults,” Turilli said. Restricting your calories to this extent can cause metabolic changes that make it difficult to manage your weight in the long term.
Should you count or track your calories?
Calorie counting is beneficial for some people since it can help you identify eating patterns and behaviors and create an overall awareness of your intake. But counting calories isn’t for everyone.
“Not all calories are created equal and counting calories has been linked to unhealthy relationships with food,” Turilli said. She recommends focusing on creating a diet that nourishes your body while making the adjustments you need to reach your health goals, rather than counting calories.
What are empty calories?
Empty calories are calories that don’t give you much nutrition but add to your total overall calories. Most empty-calorie foods are highly processed foods that contain fats that are solid at room temperatures, such as butter and animal fat. Many processed foods also contain empty calories that come from sugars, like high fructose corn syrup or white sugar, that have been added to beverages or food. If you eat a lot of empty-calorie foods, you’re more likely to gain weight, especially if you are sedentary.
The bottom line
Calories are closely linked to your body weight, so understanding what they are and how many you need can impact your overall health. To talk to a dietitian about how many calories you need and the best foods to choose, reach out to Banner Health.
