Nutrition 101...

Alright at last I got enough time to write this down. And I decided that it would be best to publish it in my blog too (Criss I hope you don’t mind). This is a very simple method to calculate your body needs & rearrange the amount of food you're consuming. Just take in mind that this is only about the energy you gain from the food not the vital nutrients you are supposed to get. That shall be discussed in another topic. (I don’t promise but if I would find the nutrition charts on line, I'd post them here. Mine are in Persian & it's no use to post them.)
To start our nutrition 101, we must learn a few expressions:
* Cal: in nutrition Science energy is measured by Cal (with capital C) which indicate Kilo Calories. So if I would write 9 Cal, then it means 9 kilo calorie. (Note: each Cal is 4.8 joules)
* REE: Resting Energy Expenditure: this is the minimum required energy for natural body reactions without any kind of physical action involved (like when you're sleeping).
Ladies generally need 0.9 to 0.95 Cal per hour for each Kg of body weight to survive. It means if you're 50 kg lady then you need: 50*0.9*24= 1080 Cal per day just to live on.
As for gentlemen the figure is 1 Cal per hour for each Kg of body weight. For example a 50 Kg man needs: 50*1*24= 1200 Cal per day.
The first step to start a diet is to calculate your REE. & no matter what, you shall not take a diet with less energy than REE (that is called straining diet)
REE is affected by some factors like fever, pregnancy, Lactation, growth age, stress, emotional experiences &.... in these cases REE might be raised up to 13%.
* Required Energy for Physical Activity (PA Coefficient):
Now comes the important part, how much Cal do you need to really get by per day? There are Coefficients which would determine your body need:
- sitting without Strenuous physical activity: 1.4-1.5
- sitting with Strenuous physical activity: 1.5-1.6
- standing: 1.8-1.9
- intense physical activity: 2.0-2.4
- Sportive physical activities 2 or 3 times per week for at least 30-60 minutes will add 0.3 to each figure.
If you multiple these coefficients (depending on your situation) by your REE, you'll get your required energy expenditure.
For instance suppose a 50 kg salesman who is standing most of the time:
REE: 50*1*24= 1200 Cal/day; 1200*1.8= 2160 Cal/day
This means he at least needs 2160 Cal per day to be able to do his job.
* TEF (Thermal Effect of Food): this is the heat released by your body after you consume food. TEF is usually around 10% of required Energy Expenditure.
So in the above example, it will be 2160* 10%= 216 Cal/day

Now we get to calculate the real Energy Requirement of your body: you shall add TEF to the Required EE. (2160+216= 2376 Cal/day in the example)
Therefore there is this simple equivalent for your body energy need: (REE*P.A) + TEF
Obviously, if you consume more Cal than the figure, you'll get fat & the less you consume, the thinner you become.
If you want to lose weight healthily, your diet should contain 10 to 15% (on top) less Cal than the figure you calculated above. Remember that a diet with less than REE Cal can damage both your health & sanity.
When you're done calculating, then it's time to manage your diet. You shall consume 40% of your Cal during lunch time. It is said that you can have 25% at breakfast & 10 to 15% at dinner time & divide the rest into 2 or 3 meals along the day.
You're supposed to receive 60-65% of your Cal through Carbohydrates (like sugar, Starch, Rice, Potato, Bread & Fibers), 20-25% through fats & 10-15% through proteins.
I hope this very basic information about Nutrition would help to somehow managing the diet & food consuming habits. Remember that this is just about the Cal you get. In a healthy diet there are other factors involved like the need for vital micronutrients, maximum & minimum level of consuming the three basic nutrients (Carbohydrates, fats & proteins), your health state & a lot more.
Please, please do not follow a diet before consulting your family doctor &/or a nutritionist. For an optimum diet you shall take into account different aspects. Even if a diet had worked fine for someone else it does not mean it's good for you too.
Yeah & remember to EXERCISE. That is the Magical Charm to lose weight.
Well, if I should be of any assist, Proshat@gmail.com is where you can leave me a message.