Calories are seen as the villain that contributes to our weight gain. However in dietary terms they are the units of energy that our food provides us. When we consumer more energy than we need, our body stores it as fat. Conversely, if we don’t take in enough energy we will lose weight in the form fat and eventually muscle.
A calorie is the amount of heat needed to raise the temperature of one gram of water by one degree Celsius1. The calories in the food we eat provide the energy in the form of heat for our bodies to function. We need this energy to maintain our health and perform our daily activities.
Calories and Weight Gain
The food we eat provides us with essential calories (energy) and nutrients we need to build strong bones and muscles. However, not all sources of calories are equal. Sugary drinks or snacks contain empty calories which means that they provide calories but have no nutritional value. Refined carbohydrates are considered an empty calorie because they lack essential nutrients.
The macronutrient composition of your food plays a role in your caloric intake. Protein and carbohydrates have less than half of the calories per gram compared to fat. Carbohydrates have 4 calories per gram, Protein has 4 calories per gram, and fat has 9 calories per gram2. Healthy eaters try to avoid fat in their diet while trying to lose weight because of its higher caloric content.
It is generally estimated that 3,500 extra calories will result in the gain of one pound3. In order to lose weight you need to create a caloric deficit by either reducing your caloric intake or burning off extra calories. For example, you can reduce your intake by 500 calories per day to lose 1 pound each week. A 1-2 pound decrease in weight per week is considered a healthy sustainable rate of weight loss.
It’s important to understand your daily caloric needs. You can use the daily caloric intake calculator below to find out how many calories your body needs to function properly. Additionally, you can use the calculator to find out how many calories you should be eating a day to achieve your target weight.
How to Lose Weight
To lose weight you need to eat less or burn more calories than you take in. Eating higher protein diets can help you manage your calories. Protein rich foods are helpful for building and maintaining muscle. When you have more muscle you can be more active during the day and burn more calories. Additionally, calories from fiber rich foods can help you feel more full. This helps you eat less and slim down4.
- Hargrove JL. History of the Calorie in Nutrition. The Journal of Nutrition. 2006;136(12):2957-2961. doi:10.1093/jn/136.12.2957
- Buchholz AC, Schoeller DA. Is a calorie a calorie? The American Journal of Clinical Nutrition. 2004;79(5):899S-906S. doi:10.1093/ajcn/79.5.899s
- CAB Direct. Cabdirect.org. Published 2020. Accessed December 30, 2020. https://www.cabdirect.org/cabdirect/abstract/19591402481
- Slavin JL. Dietary fiber and body weight. Nutrition. 2005;21(3):411-418. doi:10.1016/j.nut.2004.08.018