Calorie calculation, consumption and side effects of minimum intake

In short, my question is "How actually calorie calculation works?" Now, I will try to describe my question in detail. While surfing net I found a calculator which claimed that it can identify my minimum calorie requirement. By reverse engineering I found the formula was nothing but

My Weight * 24 = Total amount of calorie required for my body

Now,

Total amount of calorie required - 500 = minimum intake for my body.

[which truly doesn't applicable for people having 0-45 Kg]

Having said that, I have two question,

1. How much minimum amount of calorie required for my body when I am doing cardio + normal gym routine + daily home and office work? I doubt about the above formula.
2. What is the best way to reduce weight via calorie control without damaging body. Ex. If my daily intake is 1200 cal , so do I have to burn more than 1200 cal everyday to reduce my fat?

from my knowledge, more muscle consume more calorie (just like car engine, more horse power more consumption of gas), so limiting calorie intake can cause damage to my muscle growth?

Sorry for my bad English

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the calorie calculation suggestion, was that based on total pounds body weight? If so, make sure you convert your body weight to pounds first (~2.2 lbs per kg). – Berin Loritsch Apr 14 '14 at 14:08
Also, what is your starting point and goal? – Berin Loritsch Apr 14 '14 at 14:08
I am 165 lbs and 5' 11''.. as per BMI I am 27.5 which is overweight. Other than my lower belly I can't say I have much fat. I mean, my arms are well toned and curvy, so does my legs. – Zerotoinfinity Apr 14 '14 at 14:23
BMI is a statistical measurement for populations, applying it to an individual doesn't account for the individual's true body composition. The question is, where do you want to finish? You might hit BMI and still have the lower belly pretty close to the same. BTW 5'11" and 165 is a BMI of 23.0 (normal). – Berin Loritsch Apr 14 '14 at 15:15
I have no specific target, I just want to loose my belly fat (may be six pack, if exercises works for me :) ). – Zerotoinfinity Apr 14 '14 at 17:08

I think that having at least calculated a few of your baseline TDEE values can be beneficial if you're overweight and have gotten your body "used" to under consuming calories based on something like say, willpower for example.

Body weight x 24 is an absurd amount, for me that means my body would require roughly 4200 calories for maintenance. My actual calculated TDEE is ~2536. Just google TDEE calculator and you'll find the ones that are based off scientific values and even ones that let you adjust based on activity level.

The best way to reduce weight without sustaining metabolic damage is to reduce your calories by 500 of your TDEE and then readjusting your TDEE for weight lost. If you go into a severe deficit you'll lose weight for a short amount of time and then plateau. A lot of the times when someone can't lose weight even through intense exercise they're either eating too much(e.g. surpassing their caloric maintenance) or just plain not eating enough(eating enough to reach their calculated TDEE MINUS the caloric deficit).

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The BodyWeight * 24 didn't specify the units, so that is a big factor here. It could be as much as 2.2x off. – Berin Loritsch Apr 14 '14 at 14:10

There are plenty of formulas for calculating required calories. Some are even based on science. However, since every individual has different requirements based upon lifestyle, etc., I find that the best way to control and monitor calories is to become knowledgeable on serving sizes and food content. So, to answer your first question, I would not use a specific formula. Rather, I would keep a food journal that tracked the amount of calories and nutrients being consumed over a baseline period of time (say two weeks for example). With all things being equal, if you are able to maintain your current weight during that time, that should provide your maintenance calorie and nutrient totals. Now, for the second question. Having loosely calculated your maintenance calories, it's easy to make small (eg. 250 to 500 calories) adjustments to raise/lower your calorie intake based upon your goals. I would repeat this process on a regular (6 month?) basis, again, based upon your specific goals.

The most important concept to grasp is do not guess at what you are consuming for nutrients. Most people guess on the low side and underestimate their calorie consumption.

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+1 for giving a real time calculator which will be specific to my body, i never thought about that. Quote > Rather, I would keep a food journal that tracked the amount of calories and nutrients being consumed over a baseline period of time (say two weeks for example). – Zerotoinfinity Apr 14 '14 at 12:36