It is the word, regardless of its conotation, most often associated with weight loss. "Oh my god, do not become one of those calorie counting bitches." "Well, if I drink that, it'll be the rest of my calories for the day." "Think about how many calories are in that gigantic meal!" All these phrases, and more, have been present since I started actively improving my lifestyle almost two months ago. From Whole Living's Body and Soul, comes the following excerpts on the Calorie:
Back in science class, most of us learned the answer to this simple question: A calorie, like an inch, is a unit of measurement. It quantifies the amount of enery that our bodies get from food. To determine calorie counts, scientists burn food in a water-enclosed chamber called a bomb calorimeter; the number of degress by which the burning food raises the water's temperature equals the number of calories in food.
How do you use them?
To create the energy it needs, your body burns calories in a process called metabolism. It then expends this energy in several ways. The amount used for basic continuous functions (breathing, circulating blood) is known as the Basal Metabolic Rate. BMR. Even if you did absolutely nothing, your cells would still draw on energy to function; this accounts for 65 to 75 percent of your total calorie needs. Interestingly, some of your organs demand more energy than others.
Does it matter where calories come from?
From a nutrition standpoint, yes. Food provides more than just calories; nutrients such as vitamins, minerals, and omega-3s are essential for good health. But let's focus on two other factors; the energy a food provides and the pounds you gain, or more important, would like to lose.
Energy can come from any of the three macronutrients: carbohydrates, protein, and fat. For quick energy, it's hard to beat carbohydrates. Your body breaks them down and converts them to glucose, its favorite energy source, more easily than it breaks down fats and proteins (which is why marathon runners often indulge in a big pasta meal before a race.) While some cells in your body can use either fatty acids or glucose for energy, your brain and nervous system run solely on glucose. Fat contributes energy for sustained activity, but some of the fat you eat goes into storage to be used later when-and if- needed. So what about protein? It, too, can provide energy, but it takes the most effor to convert. Your body prefers to use it to build and repair tissue (muscles!).
How many calories do you actually need?
Your body requires enough calories to fuel its basic functions. To blankly calculate your needs, find an online calculator. Look for one that accounts for your height, weight, age, sex, and activity level (check this one out HERE). Keep in mind that these tools are generalized.
How do you burn them?
Programmed to hold onto energy (i.e. the extra weight you're trying to lose), your body doesn't likie to waste calories. To lose fat, you need to expend more calories than you take in--3,500 for each pounds.
Let's say you operate at a deficit of -500 calories per day. After seven days, you've added up -3500 calories, or one pound per week. Congratulations!
You can create that deficit by eating less, exercising more, or ideally, BOTH. For example, skip the roll (100 cal) with butter (100 cal) and that serving of chocolate ice cream (250 per 1/2 cup), and you're well on your way. Add a half-hour walk at a moderate pace (burns 100 calories) and you've already passed your 500 calorie reduction for the day.
Going too low--1,000 calorie deficit per day--is not only difficult to maintain but can sabatoge your efforts by causing your metabolism to slow down and conserve energy.
So....metabolism. Tune in next Tuesday for a Truth Tuesday all about how metabolism affects your body!