Now that we know what BMI is and our ideal body weight, lets talk about something that is a bit more simple: calories. While most people have a basic concept of what a calorie is, watching how many calories you eat and how many you burn off is an important concept, so lets talk about it a bit here.
First, it is VERY important to note that most overweight or obese people really don’t realize how many calories they eat every day OR how many calories they burn off with exercise. In fact, surveys show that more than 90% of obese people think they are eating fewer calories than they really are.
The scientific definition of a calorie is “the amount of energy needed to raise 1 kg of water 1 degree Celsius”. In normal language, it is simply term that we use to measure energy and how your body stores energy. Just like pounds is the unit to measure weight, calories is the unit to measure energy.
Now, as a general rule 1 pound of excess body weight holds about 3500 calories. So to lose 1 pound, you need to burn off 3500 more calories than you eat through exercise or other means. Sounds like a big number, but as you will see its not that bad when you break it down in detail.
Calories that you eat in your diet and calories that are stored in your body come in the form of fat calories, carbohydrate calories or protein calories. When we measure how you performed during an exercise session, one of the factors we will consider is the amount of calories you used up during the workout. The number of calories AND the type of calories that you use during exercise is influenced by a number of factors including:
- Duration of exercise
- Intensity of exercise
- Type of exercise
- Food intake before exercise
Now, it is import to note that the ACC/AHA/TOS Guidelines for the treatment of obesity recommends women keep their daily calorie intake to 1200-1500 calories and men keep it to 1500-1800 during a weight loss program. Most importantly, they recommend a net negative calorie deficit of 500-750 calories per day. This means that they want you to burn off 500-750 more calories every day compared to what you eat. This concept makes it seem like counting calories is critical, but as we previously mentioned, eating large amounts of fruits and vegetables in a whole foods plant based diet will make counting calories unnecessary.