Calories are how we measure the energy that our body uses for fuel. They power our bodies’ vital processes, like breathing or even sleeping.
The amount of calories in our food reflects the amount of energy that food provides our bodies. Calories come from macronutrients, a.k.a. carbohydrates, protein, and fat.
Carbs are the body’s main source of fuel and are easily used by the body for energy. Carbs break down into glucose, which is used for energy. They’re also stored in muscle and liver for later use and are important for the central nervous system, kidneys, brain, muscles, and intestinal health. You can find carbohydrates in grains, fruits, milk and yogurt.
Protein is essential for growth, tissue repair, immune function, preserving lean muscle, and producing essential hormones and enzymes. The body used protein for energy when carbs aren’t available. You can find protein in meat, poultry, fish, cheese, milk, nuts, and legumes.
Fats are essential in cell, nerve tissue, and hormone production. Fats are also essential for absorbing fat-soluble vitamins like vitamins A, D, E, K, and carotenoids. Fats are the most concentrated source of energy. If fats consumed aren’t burned as energy or used to build body tissues, they’re stored in the body’s fat cells for later use. Unsaturated fats such as olive oil, avocado, nuts, fatty fish, and canola oil.
In terms of energy they deliver, all calories are equal. However, the body uses each macronutrient differently. The right amount of calories from each source is very important to ensure the body can function properly.
When choosing what to eat and drink, it’s important to get the right mix – enough nutrient, but not too many calories.
To maintain weight, calories in (what you consume) must be equal calories out (what you burn on a daily basis through normal body functions and daily activity/exercise).
When you burn more calories than you consume, you lose weight. When you consume more calories than you burn, you gain weight. The general rule is consuming +/- 3,500 calories per week is equal to 1lb. of body fat gained or lost.