MASS BALANCE vs FAT LOSS
**Reality check please ? Am I thinking right with this **?
Bill the newbie here, Is there a way of standardising the measurement of weight in order to minimise the impact of the last meal / drink / exercise session / bathroom visit ?
ie after fasting for 24 hours and not drinking anything for 4 hours ?
Some Jumbled Thoughts
Seems to me that as you approach ideal weight then the scales become less relevant and other ways of measuring fat become more relevant. ie tape measure around tummy, calipers, etc
Unless you do some sort of cardio between measurements (weekly or daily or monthly) and are 100% confident you have burned some excess fat, you might only be measuring differences in mass balance ie food & drink in vs sweat + waste material out.
Made me start to think about what "weight" really is, mine can fluctuate by up to 1.5kg on a daily basis depending upon the timing of the measurement relative to the last input, output and exercise.
So when a doctor asks you what do you weigh and its really really important to get it right for example a critical dosage of drug XYZ which is very sensitive to body weight, what do you tell him ? I guess 1.5kg out of 82 is only approx 1.8% so wouldn't be too important.
You raise some really good points! There is no such thing as one "true weight"; our weight is in constant flux and a reflection of normal physiological processes.
Weighing yourself at the same time of day (i.e. when you wake up, after peeing, wearing no clothes) can help to control some of the outside influences since our body tends to operate on a 24 hour circadian rhythm.
Also, when you are measuring your weight, pay closer attention to trends and shifts vs. absolute numbers. (For example, I tend to look at month-to-month changes in weight since this is more reflective of true changes. In a weekly/daily period, I expect weight to fluctuate by as much as 5 lbs.)
The gold standard measures of body weight are DEXA (commonly used to measure bone mass) or bod pod. But accessing these machines can be quite expensive.
Also, medication dosing is typically for a weight range vs. an absolute number, so you should be fine.
Susan Macfarlane, MScA, RD
Registered Dietitian Nutritionist
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First thing I do each day after waking is go to the bathroom then weigh myself. There is still plenty of fluctuation in the daily measurement even if my clothing is the same every day. I think the primary driver of the fluctuation is water retention and suspect that there is some correlation with my recent sodium intake. I use at least two weeks worth of data to evaluate any trends. If reporting my weight to others, I usually round to a multiple of 10 (sometimes in the direction of my trend rather than to the nearest - especially if it's going on a long term document such as an id card).