Scientific approach to weight loss:
Everybody always wonders what the secret to weight loss is; well the fact of the matter is there is no secret to it. There are a few equations and scientific facts that, when used, can easily tell you exactly what you need to do in order to lose (or gain if that's your goal) as much weight as you want.
I am going to take this step by step, I just ask that you stick with me till the end and you will have a guaranteed way (mathematically proven!) to meet your weight goals!
Because the long term gain or loss of weight, by that I mean loss of fat or gain in muscle, starts with the number of calories we eat. This exhibits the first scientific law to weight management: the law of conservation of mass. Calories are fuel for our body, if you do not burn the fuel you ingest then it is stored. It is as simple as that, you will not gain weight if you are burning as much or more fuel then you consume, that simply is not physically possible.
Knowing this then we must first find out how many calories it takes for us to maintain our current weight. This is important because knowing this I will tell you exactly how many calories to cut to meet your weight loss goals, that final number of daily net calories is the most important.
Finding out the calories needed to maintain your current weight
In order to determine how many calories we need to maintain our weight, we first must determine our basal metabolic rate, which will be known as BMR from here on out. To calculate this is a simple task using one of the two equations below depending on your gender:
655 + (4.3 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)
66 + (6.3 x weight in pounds) + (12.9 x height in inches) - (6.8 x age in years)
Once you have that number you use what's called the Harris Benedict Equation, which is a multiplier that depends on what your activity level is, to give you the final result for number of calories needed to maintain your current weight.
Because this is somewhat subjective it's important to be honest with yourself and double check the final results with common sense. If you say you're moderately active but the final number of calories needed to maintain your weight is 30% higher than what you eat daily then chances are you're maybe more sedentary then you give yourself credit for.
That being said, the following are the Harris Benedict Equations, take your BMR (calculated above) and plug them into the appropriate place below:
Sedentary (no exercise, at most light activity once a week): BMR x 1.2
Lightly Active (Light exercise 1-3 days a week): BMR x 1.375
Moderately Active (moderate exercise/sports 3-5 days a week): BMR x 1.55
Very Active (hard exercise/pushing yourself hard in sports 6-7 days a week): BMR x 1.725
Extra Active (twice a day heavy exercising or work a job that is hard physical labor): BMR x 1.9
The resulting number will give you the number of calories you need to eat daily in order to maintain your current weight. Ta-Da!
Now that's all well and good, but I still haven't told you anything about using this info for weight loss, well wait no longer!
The key fact to remember here is that, in one pound of human fat there are approximately 3500 calories stored. That is to say that for every extra 3500 calories you don't burn, your body stores it in one pound of fat. Knowing this it is simply a matter of asking ourselves, well if we want to lose a pound of fat that means we need to burn 3500 calories.
Now let's go back to the number of calories we need to eat in a day to maintain our current weight, do me a favor and multiply that number by 7, this is now how many calories you need to eat in a week to maintain your current weight.
We now know that to lose a pound of fat we'd need to burn 3500 calories. Therefore we can reason that if we maintained the same level of activity, but reduced our weekly calorie intake by 3500, that we will have effectively burned an extra 3500 calories that week since you're still burning the same amount of fuel but reducing the amount you're consuming.
Now 3500 over a week is fine, but to simplify we'll just call it 500 a day (500 calories x 7 days = 3500 calories a week). So the final conclusion is to take the number of calories you need to maintain your weight (calculated above) and reduce that number by 500.
If you honestly keep the same level of activity you have been and carefully watch what you eat, sticking to this plan you should lose one pound per week!
A word on nutrition and metabolism
Everything I've told you is pretty common knowledge in the fitness and nutrition field and has been proven, but I will tell you right now that everyone's body is slightly different and it may take more than just a week or two in order for your metabolism to get to this point. The key here is that you will get to this point but it may not happen instantly.
Also it is important to note that I only discussed calories here, but calories come from many sources; fat, carbs, proteinsâ€¦ It is important not only to watch the quantity of what we eat, but also to watch the quality. You might lose weight if you cut your daily calories by 500 but if 90% of your daily calories are still coming from fatty junk food you'll still be in pretty poor health. All I'm saying is to use common sense with what you eat and watch the calories and you'll be just fine.