By: Raheel Anwar
How many calories can I really eat is a question that many of us ask ourselves, every single day. There is a specific amount that we should eat, and it’s based on our age, weight, gender, and general daily movement. We always hear words like metabolism, but many people don’t know what that truly means. Our body undergoes millions of types of chemical reactions every day, to keep us alive. Our metabolism is the total amount of energy our body uses to drive those chemical reactions. Thus, as you get older, and your metabolism slows down, your body is not undergoing as many chemical reactions in 24 hours as it used to when you were in your teens. This means that you technically need to consume less energy (calories) from food, per day, to stay at the same weight. If your food intake remains the same, then your weight will slowly increase. You can think of it as a car, if we keep putting more and more gasoline into our tank everyday, and our engine isn’t burning up all of its fuel everyday, eventually there will be an excess of fuel in the tank. Our body takes that excess “fuel” and stores it as fat, in our fat cells, also known as adipose tissue.
You’re probably wondering how to calculate how many calories you should eat in a day, and it starts out with calculating your Basal Metabolic Rate (BMR). What is that, you ask? Your BMR is how much energy your body requires every day to simply sustain life, with out any other expenditure. Suppose you woke up one day, and laid in bed all day and night until the next day, and didn’t even move an inch all day. We calculate BMR using the following formula:
BMR = 655 + (4.35 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)
BMR = 66 + (6.23 x weight in pounds) + (12.7 x height in inches)- (6.8 x age in years)
After you calculate your BMR, you can calculate your total caloric intake by multiplying it by an activity factor that corresponds to how active you are on average, per day.
If you are sedentary (little or no exercise) = BMR x 1.2
If you are lightly active (light exercise/sports 1-3 days/week) = BMR x 1.375
If you are moderatetely active (moderate exercise/sports 3-5 days/week) = BMR x 1.55
If you are very active (hard exercise/sports 6-7 days a week) = BMR x 1.725
If you are extra active (very hard exercise/sports & physical job or 2x training) = BMR x 1.9
So, for example, if I am a 20 year old, 6 foot male that weighs 200 pounds and I am
moderately active, my total caloric intake would be as follows:
Step 1 = Calculate BMR
(6.23 x 200 lb)
(12.7 x 72 inches)
(6.8 x 20 years)
66 + ((1246 + 914.4) – (136)) = 2090.4 calories
Step 2 = Multiply by Activity Factor (Moderately active in our example)
BMR x 1.55
(2090.4 calories) x (1.55) = 3,240.12 calories
This means that as a healthy, moderately active, 6 foot tall 200 pound male, I would need
to eat 3,240 calories to maintain my weight. If I eat more calories than that, I will gain weight, if I eat less calories than that, I will lose weight.
I hope this provided some initial insight into maintaining your weight, if you have any
Questions, leave them in the comments!