# Wording: 0% or NO?

I need to represent a stat for a weight loss stat. Right now I have this wording:

2% weight loss

the client hasn't think of the logical scenario of no weight loss or even worse, weight gain. So I'm working on this but still dubious on wording between these two:

0% weight loss

or

No weight loss

I really don't like the 0, it doesn't scan well and makes no much sense for me, however "no weight loss" seems widely open, since it could be "you didn't lose weight", or "you gained some weight" (and if so, how much?).

So, what is more appropriate? 0% or NO?

Note: 0 or NO are the only possible options because of space limitations

• If you're worried about "No weight loss" being misinterpreted, may I suggest "No change in weight," or something to that degree. – Andrew Gies Aug 27 '15 at 3:52
• Somewhat related... weight loss as a percentage of total body weight is a very difficult metric for most people to put into perspective. Considering normal dietary weight losses and measurement intervals you would usually be between 0 and 1 percent. – freekvd Aug 27 '15 at 6:18
• Stay positive. "No weight gain" sounds better than "No weight loss" (At least if the goal is to loose weight. If the goal is to gain weight then you might stick to your current wording) – BlueWizard Aug 27 '15 at 15:13
• Adding the 'weight loss' part to the heading of the question would be nice, since it is the text of all links leading to this page as well. Now the links are somewhat cryptic. – Pavel Aug 27 '15 at 16:26
• I'd argue those mean different things. %s could go into the negative if you actually gained weight, whereas 'no weight loss' wouldn't. – DA01 Aug 27 '15 at 21:33

Is there room for

no weight change

This is then easy to understand, and is clear that it's not any gain either.

Like the answer, I think you'd more than likely say something like "my weight hasn't changed since last week"

On a similar note, a 2% loss doesn't mean much to most, so would it be better to say

6lbs weight loss (2%)

• Another +1 for your final point. It might still be confusing, though: 2% of what? My weight? My weight loss goal? – Celos Aug 27 '15 at 13:16
• I was scratching my head figuring if it would mean 2% of my starting weight or from the last time i got weighed. Directly saying "6lbs loss" leaves 0% ambiguity ;D – NachoDawg Aug 27 '15 at 13:40
• KThank you for your answer. As for your last point, don't worry, it already has the absolute weight in lbs and/or kgs, but the percentage is absolutely required and even most needed than absolute values. In weight loss, percentage is the norm, since in a comparison between different people, users need to lose a percentage, which is more accurate than absolute. Someone with 300lbs weight needs to lose a lot more (in absolute terms) than someone weighin 180lbs – Devin Aug 27 '15 at 15:12
• @Devin but % of what? weight when starting the program? weight when last weighed? It would make some sense if it was % of weight loss goal, as then a person who wanted to loose 20 lbs could see that they made it 5% of the way to their goal if they lost 1lb. Or someone who wanted to gain 10 lbs could see a percentage towards their goal that makes sense. – Rick Aug 27 '15 at 18:02
• @Rick and NachoDawg: As you may imagine, I didn't add the complete context, because it wasn't needed, the only thing I needed is the wording, and I solved it. The context takes care of your concern and it's extremely clear (just in case you're curious, it's from an initial weigh in). This being said, I really appreciate your input, although can't see how is this related to teh question at hand, it helps me as well as anyone that reads this question in the future – Devin Aug 27 '15 at 21:14

The most appropriate is NO

According to one of the 10 Usability Heuristics for User Interface Design by Nielsen:

The system should speak the users' language, with words, phrases and concepts familiar to the user, rather than system-oriented terms. Follow real-world conventions, making information appear in a natural and logical order.

When you tell a friend that he has no weight loss, you don't tell him that he has 0% weight loss. Instead, you would just use the word "no".

• +1 Nature language is always a good choice/default when it doubt. Of course, it should be tested to see if this assumption is correct. – Michael Lai Aug 26 '15 at 23:36
• I voted this up and tempted to mark this as correct answer. however, what about the perception of "broadness"? Maybe it's just my idea since in my language it's even more undefined – Devin Aug 27 '15 at 1:22
• Devin, do you mean that the "0% weight loss" may be more natural in some languages than "no weight loss"? – Max de Mooij Aug 27 '15 at 1:29
• No, not really, just that it sounds more accurate while the undetermined option is... Well undetermined. Anyways, probsbly my OCD side acting up! – Devin Aug 27 '15 at 3:52
• Assuming you are weighing people, if you want to want to keep the precision add precision. 0.01% weight loss or 0.01% weight gain is 0.05 pounds on someone at 500 pounds. At a closer 100-300 range it's 0.01-0.03 pounds. "no weight loss" can be a problem if you show a graph next to it. Specially if that graph auto scales. "No weight loss" next to a big graph that shows big peaks and valleys is worse then "0% weight loss". All that is to say, it's dependent to what your trying to say. If it's for a new use, I would display "No Data Yet" and some tips. For an established user, 0%. – coteyr Aug 27 '15 at 4:39

# Neither

Who on earth measures weight changes in percentages?

## The problem with percentages

• In general, percentages are always a proxy variable and mostly little intuitive.
• Everyone has to expand some cognitive effort to do the maths, and quite a few struggle with the percentages maths (some can't do it at all).
• When time is a factor, percentages get ambiguous - if you lost 2% on week one and 2% on week two, did you lose 4%? Was the base rate for the second measure the weight on the first or second week?
• Percentages are relative - if two people lost each 10% in 3 months, it is much more of an achievement for someone who weighted 160kg (lost 16kg) than to someone who weighted 60kb (lost 6kg).

## The benefit of percentages

Percentages are great when there is a fixed lower limit (often 0), and fixed upper limit. If data allowance is 2GB per month, most people would prefer to know they have used 80% of it, than 1.6GB. I'm afraid weight neither has an absolute lower limit, nor an upper one.

Another place where percentages are great is when you compare change between figures that has different reference point. So if Apple stock went up 5% and so did Google's - their performance is on par; much easier than being given the start/end stock value (which in itself depends on the amount of stock shares). But I doubt you aim to compare such change.

# Summary

The point is that in everyday language, weight changes are measured in Kgs, lbs, or stones. So what is the case for percentages?

• stones? that is too geo localized and nowhere close to the widespread use of lbs! Either way, as I explained, the percentage is absolutely needed because the goal is to lose X percentage, so this is the correct metric – Devin Aug 27 '15 at 21:09
• @Devin OK. What you have just said puts the question in a completely different context (we do have fixed start/target), which I'm afraid may render current answers invalid. I ask you: If you haven't used any data this month, would you prefer a meter saying 'No data used' or '0%'? – Izhaki Aug 27 '15 at 21:13
• Thanks Izhaki! I think this is an interesting addition, especially the relative & absolute statistics. – Max de Mooij Aug 27 '15 at 23:17
• *percentages are also useful when the actual number is of little consequence. Imagine two companies who's stuck goes up by 2.5. That might mean a 0.01% growth for company A, or a 200% growth for another! – Dirk v B Aug 27 '15 at 23:56
• @Devin Your questions is precise, your comments in place and everything is cool, except that too geo localized comment - I don't know stones, and I can just approximate lbs ;) But you can probably only approximate kilograms, so all of them are geo localized. Just being a nitpick here, probably, but I had to let it out :) – Zlatko Aug 28 '15 at 14:11

I'd go with [+/-] <Amount> <Weight Unit>/<Duration unit> e.g. +1Kg/1Week or -2Lbs/1Week or 0Kg/1Day, so the difference per duration is clear.

Regarding the percentage, it isn't clear what the percentage is relative to - What does the 100% represent? E.g. initial weight, desired weight, weight at the beginning of the current time frame or (the best option in my opinion for encouraging people to continue, since it makes it more clear how effective the diet is...) initial weight - desired weight.

If you do choose to go with a specific definition of 100% (especially the latter example), then you could add it to the above e.g. for a 10Kg loss plan, if someone looses 1Kg in a certain week: -1Kg/1Week (10% lost) and then you can summarize the process so far with -6Kg/3.5Weeks (60% lost).

0% could potentially mean a small percentage, but not completely immeasurable. A 200-pound being losing just under 1 pound would have lost 0%, but it is by no means nothing at all. Use No weight change when nothing has been lost or gained within normal variation. Saying "No weight loss" sounds like "Well, you didn't lose any weight... you put some on instead."