# A useful formula for fat loss

I transferred all my blogs to this new site, and somewhere is the first blog to this, which  talks about losing 1kg a week. Otherwise known as a 7000 calorie deficit / or 1000 calorie deficit a day.

This blog today talks about the numbers in more depth. So, let's get some numbers down to make this work for you.

B = your BMR (the magic number that we can only guess or use textbook guidelines for)
C = Calories eaten
E = Exercise
D = Deficit

We know that C - (B+E) = D

In english that means, We eat calories (C) we subtract our BMR and our Exercise (B+E) and we should have a calorie deficit (D)

And here it is with a couple of random numbers, C=1500 / B=2000 / E=400
1500 - (2000 + 400) = -900.

So if every day I eat 1500 calories, exercise 400 calories and assume my BMR is 2000 calories then I will get a 900 calorie deficit - which is pretty close to getting me a 7000 calorie weekly deficit and therefore a 1kg loss.

But I have to do this every day. Or at least make sure it averages out to this every week. Guess what that means? Dig deep and don't cheat yourself.

Righto - but what if we just don't know our BMR? We can still use the same formula.  This is where basic algebra skills are quite handy.

C - (B+E) = D

Lets say I KNOW that I burn around 500cals a day in exercise. Let's say I KNOW that I eat 1200 calories. Let's say I have also experienced a 1kg a week weight loss every week for the past 4 weeks, so I KNOW my calorie deficit is probably around 1000 a day.  I have 3 numbers and I just need to work out the 4th one.

1200(C) - (B+500)(B+E) = -1000(D) (note the minus sign)

all we do is move our  +C over to the D side and turn it into a minus (because it has crossed the equal sign)

1. (B+500)(B+E) = -1000(D) - 1200(C)
2. -1000(D) - 1200(C) = -2200(B+E)
3. So, our B+500(E) has to equal 2200(B+E)
4. -2200(B+E) - 500(E) = -1700(B)
5. B = 1700

OK, So I understand that we're not all algebra scholars. The easiest thing to do is to take your C, D, B and E numbers you know and replace my numbers for them into bullet points 1-5.

Why is this important?

Well, we don't know your exact thyroid function and we don't know what other factors are either speeding up or slowing down the magic theoretic number that we call the Basal Metabolic Rate. Sure, you can use the basic guidelines that says a female burns 2200cals a day just by living, but if you don't lose weight then you have to ask yourself, is your exercise not burning enough? Are your food calories too high? Or have we grossly over calculated your BMR.

Also, wouldn't you like to know why you're getting a 1kg loss a week? We can be simplistic and say - If I eat this and do this I will get 1kg a week. But what about in 2 years time when you get a little relaxed and start putting weight on? Surely you want to know what your numbers are so that you can work out what your MAINTENANCE calories are going to be.

If this is complicated, then its a good idea to hire me or someone like me to teach you this. Know your numbers, and don't give up if you aren't seeing weight loss.