who can answer the Math of Weight Loss?

zelannie

Can someone explain what the true math of calorie deficit is? i get it in principle but am confused by the calories eaten less the calorie burn at rest and the calorie burn of extra exercise to net the calorie deficit.

I am eating 1200 calories daily (tracked maniacally, weighing everything i put in my mouth for past 32 days).
according to my UnderArmour Heart Rate Monitor (which i plug into MFP), it says i am burning 1000 calories a day while running.
my resting calories burn is about 1600 a day.
One would think that i'd see a significant weight loss and i have not.

how much weight should i be losing weekly with the above stats? I would like to know the arithmetic of calculating this because i do believe that weight loss is simple math. Calories consumed less calories burned = calorie deficit. 3500 cals = 1 lb

i've seen no weight loss for 10 days and am now thinking of just ignoring the scale and continuing because it's likely a plateau and this is just simple math. it has to work. i am not cheating or miscounting calories because i weigh and scan everything i eat and in fact, probably overcount amounts logged to cover marginal errors; meaning there are days i eat 1000 calories. and I am running 6 days a week for last 3 weeks. i need to lose 40lbs which means that i should be easily losing 2 lbs a week or so?

i am frustrated but i am also not quitting. this has to got to work.
what am i calculating wrong?

SideSteel

It's not simple math.

Calories out consists of energy expenditure from disgestive processes, base metabolic rate, non exercise activity, and exercise activity.

When you weigh yourself, you're only determining your weight, you are not determining differences in non tissue weight such as water retention, food volume moving through your system, etc.

Calorie intakes all have sources of error to them because food labels are not necessarily accurate.

Human beings make substantial errors in tracking intake and we have several pieces of research to demonstrate this, some of which I've placed in this thread:

http://community.myfitnesspal.com/en/discussion/10012907/logging-accuracy-consistency-and-youre-probably-eating-more-than-you-think/p1

Also, calories in and calories out are related in that they can interact with each other. For example some people respond to additional calories by upregulating energy expenditure to burn off a greater portion of those excess calories than other people which is one mechanism that can explain differences in weight gain across people when given similar calorie surpluses.

Now to be clear, weight loss is still primarily a matter of calories in vs calories out and I'm not claiming otherwise. But the idea that it's a "simple" math problem is incorrect in my opinion. It is complex

Liftng4Lis

10 days is a stall, not a plateau and also, not long enough. Be patient, it will come.

Packerjohn

How many miles are you running a day to burn the 1000 calories? A 150 pound person burns around 100 calories a mile running or walking.

Sued0nim

1000 calorie burn ..sems extremely high please explain this?

The way the maths work is burn more than you eat = weight loss, eat more than you burn = weight gain

Roughly 3500 calories = a pound

However all calorie intake is an estimate, all calorie burn is an estimate, the body works like a black box and each one is unique so over time you have to work out your own calorie burn ...be as exact with the calories you eat as possible

Give it time

Allow for water weight by exercise change-up, hormones, sodium which can mask up to 10lbs of scale weight

kbsmitty

This is where I get confused. So on MFP I should be close to 0 on net calories after all calories from food is put in and all calories burned from exercise? I have a goal of 1155 net calories and stick to it but that is also factoring in my exercise so technically I may take in closer to 1800. It's been 2 weeks and no weight loss. Getting very discouraged but if I have been going about this all wrong that could be why. Please help.

Sued0nim

kbsmitty wrote: »

This is where I get confused. So on MFP I should be close to 0 on net calories after all calories from food is put in and all calories burned from exercise? I have a goal of 1155 net calories and stick to it but that is also factoring in my exercise so technically I may take in closer to 1800. It's been 2 weeks and no weight loss. Getting very discouraged but if I have been going about this all wrong that could be why. Please help.

What?

No on MFP your net calories should be your goal amount

That would never be 1155 as 1200 us minimum ever set

You need to weigh and log food

You need to adjust MFP calorie burn on exercise by 50% because it overestimates

EvgeniZyntx

The principal is a pretty simple, the actual math application as SideSteal notes, is quite complex.

Consider the principal:


Yet.... there are confounding elements. For example - one can see non calorie weight gain from:

-swelling after sport
-disease related inflammation
-time of month
-salt consumption
-water under-consumption
-undigested food
-medications, etc.

Those elements don't go into the general equations.

In order to eliminate those variables you focus on longer term process - average your weight measurements, average your consumption over time.

10-14 days is nothing in the matter of measurements.

If you want to understand the mathematics of weight loss - this post does a good job of covering not only the basics but also applying them to MFP settings:

http://www.myfitnesspal.com/topics/show/819055-setting-your-calorie-and-macro-targets