How Many Calories Do I Need A Day?


How many calories you need a day will depend largely on your goal: are you trying to lose fat, maintain your weight, or gain weight (be it muscle mass or fat)?
No matter which route you choose, the first thing you need to determine is your BMR. That stands for Base Metabolic Rate, and it's the total amount of calories you need to consume per day just to keep your body alive and functioning properly. (If you're not interested in this part, feel free to skip to the end of this text to find out exactly how many calories you need.)
To calculate your BMR, use the appropriate formula from the two below. I will go through an example in a moment so don't get scared if numbers aren't your thing.
For guys: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] + 5
For ladies: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] -161
This will tell you the number of calories your body would require to stay alive if you were laying in bed 24 hours a day and doing nothing at all. Obviously that wouldn't be enough, so now we need to determine your TOTAL daily calorie requirement. To do that, take your BMR and use the appropriate activity multiplier from below (again, I'll give you an example in a moment):
1.2 = Sedentary (Desk job, and Little Formal Exercise)
1.3-1.4 = Lightly Active (Light daily activity AND light exercise 1-3 days a week)
1.5-1.6 = Moderately Active (Moderately daily Activity & Moderate exercise 3-5 days a week)
1.7-1.8 = Very Active (Physically demanding lifestyle & Hard exercise 6-7 days a week)
1.9-2.2 = Extremely Active (Athlete in ENDURANCE training or VERY HARD physical job)
Let's go through that example I promised.
Suppose your a male, 25 years of age, 170 cm tall and weigh 80 kilograms. We use the BMR calculator for males from above, and substitute the values as follows:
BMR = [9.99 x 80 (kg)] + [6.25 x 170 (cm)] - [4.92 x 25 (years)] + 5
Using basic math, we calculate that:
BMR = 799 + 1062 - 120 + 5. This equates to exactly 1746 calories. That's your Base Metabolic Rate.
Now you will need to multiply it by your activity factor. Let's assume that you lead a sedentary life style with little or no physical activity whatsoever. A quick look at the list above will show that the activity multiplier you need to use is 1.2. So we get:
1746 (BMR) x 1.2 = 2095 calories. This is your TOTAL cost of living per day.
Now, to find out exactly how many calories you need a day, you do the following:
If you want to lose fat, subtract 500 calories from the above value. 2095 - 500 = 1595 calories that you need to consume per day. If you do that, you will lose a steady 1 lb of fat per week. If you want to lose fat a little faster, you can subtract a little more than 500, though it's unhealthy to go higher than 700.
If you want to sustain your weight, don't subtract any calories and eat exactly the 2095 calories from the example above. You might notice a very slight change in weight when you that - in that case, simply subtract 100 calories (if you gained weight), or add 100 calories (if you lost weight). Stop adding or removing calories once your weight stays constant for a minimum of 2 weeks.
If you want to gain weight, add 400 calories to the value above. 2095 + 400 = 2495 calories. What's important to note at this point is that if you are not lifting weights regularly (3 times a week), the weight you gain will be mostly fat with very little or no muscle at all. If you do lift weights, however, most of the weight you gain will be muscle mass, with little or no fat gain at all.
About the author: Mark Nazzal specializes in 1 on 1 online weight loss and fitness coaching. You can contact him for help with your specific dieting or exercising issue through his website, where a large number of helpful articles are also available: Help Me Lose Weight