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afcagroo t1_ittcp8c wrote

A lot of digital scales struggle with repeatability (and accuracy). As made, you might step on and off several times in a row and get somewhat different results each time.

So the scale manufacturers came up with a cheat. The scale remembers the last measurement, and if the new one is close to that, it just reports the old one. That makes it appear to have wonderful repeatability, when in fact it doesn't. This also leads people to believe that the scale must be more accurate than it actually is.

But most of them only remember the last measurement, so there's an easy way to beat them. Weigh yourself, step off and pick up a moderately heavy object (a kg is plenty). Weigh again. Now put the object down and re-weigh. You'll likely see that your 1st and 3rd measurements, which should match, don't.

Of course, with a scale like that you aren't going to get accurate measurements just by eating 421 g of chicken. Or at any time, really.

TL;DR - Your scale is crap.

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ScienceIsSexy420 t1_itt85t7 wrote

I've noticed a similar phenomenon on my home scale, it's almost like it has a memory or something. If I weigh myself while holding a 15lb weight, then weigh myself without the dumbbell, the number changes. Trying doing a similar experiment but while holding a heavy mass between weighs

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StarVoyager96 t1_itt932d wrote

Scales aren’t always 100% accurate and they may not be sensitive enough to pick up on small changes in weight. I would try the test again with a more accurate and sensitive scale. But regardless of what the scale says you can be assured that your friend’s weight increased by the weight of the food he/she consumed.

Try taking a heavy dumbell that you know the weight off and weigh yourself without it and then with it and see if the number changes by the same weight as the dumbell.

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meistermichi t1_ittagfj wrote

> But regardless of what the scale says you can be assured that your friend’s weight increased by the weight of the food he/she consumed.

Only if you disregard him also loosing a tiny bit of weight while he is eating those wings, be it by sweating or just his base consumption of calories.

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Flair_Helper t1_ittikki wrote

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