Google ‘how to lose weight’ and you’ll come up with thousands of hits; the goal might be the one of the few true commonalities of the human race (right behind love of Coca-Cola — which perhaps explains a lot — and ahead of ‘back in my day’ reminiscences). But it’s actually the wrong goal, and fixating on the numbers of a scale can keep you from the right one: getting healthy. You see, it’s entirely possible to be fat and fit, or thin and unhealthy. Here’s why you shouldn’t use your kilos of weight loss as a measure of good health.

Seriously, throw out the scale, because …

Scales only tell you kilos, when what you really want to lose is fat.

When we talk about weight loss, what we really mean is we want to lose fat. But weight comprises a lot more than simply fat. Water, muscle, bone, and other tissues also contribute to our total body weight. (The taller you are, the more you’ll have and need of all of these things, fat included, so never try to hit the same weight as someone shorter.)

Fat, even for the heftier among us, is unlikely to contribute more than 30% to our total body weight, which means we have a lot of other important things to lose during weight loss. For instance, if you start eating fewer salty foods or carbs (a shift most diet plans are built around), you’ll probably notice a quick drop of a few kilos. But this is likely water weight, not fat.

In the same way, it’s entirely possible that gaining weight does not mean gaining fat. This is not only likely, but it can be a good sign. If you’ve upped your exercise regimen in your quest to lose fat, you’re likely building muscle, which is denser than fat. So, while your body may be changing shape, your scale may say otherwise and actually show you’ve gained weight because of your increased muscle mass.

Don’t be dismayed – building muscle (and the weight that comes with it) is a good thing for health. Not only do muscles burn more calories (6 a day, to fat’s 2 while you’re at rest), good muscle tone is linked to everything from increased immunity to a longer life.

Plus, weight variation is normal and frequent.

Weigh yourself throughout any given day, and you’ll find your scale turns up a different number each time. That’s not because it’s broken (although scales are frequently inaccurate due to their age, calibration, or the surface on which they sit). It’s because the human body is constantly in a state of flux, with every exhalation, drink, bite, bathroom break, workout and even weather pattern influencing weight variation.

To test this, two years ago, Martin Robbins, a reporter for The Guardian, did a little experiment: For three days, he weighed himself every hour, on the hour. He found his weight variation swung wildly up and down throughout each day.

“…what I think it shows is just how unreliable any single measurement of weight is,” Robbins wrote. “On any given day my weight varied by about four pounds, with a dozen pounds passing in and out of the giant meat tube that is me at only vaguely predictable times. When you consider that a sensible weight loss target is maybe 0.25lbs per day, you can see how on most days that’s just going to be swallowed up in the noise.”

Finally, weight loss is very difficult – and the effort may backfire.

We’ve written before about why it’s so difficult to lose weight and keep it off. Briefly, each body has a “set point,” that is, a weight norm, that it fights to maintain and return to, even once we lose fat. This isn’t to say it’s not worth the effort, particularly if you’re struggling with obesity or other weight-related health issues. But losing fat is a long-term challenge and progress isn’t best measured on the scale. Trying to do so – counting kilos – can actually hinder your efforts.

“Psychologically it causes havoc with individuals who weight themselves daily,” says fitness expert Neville Wadia, of Alchemy in Mumbai. “Having a weighing scale at home is a curse more than a boon; weight fluctuates daily, which leads to mood fluctuations and bad choices of nutrition.”

Wadia advises weighting yourself no more than once every two weeks and in tandem with measures of actual body fat, like waist circumference (endorsed by a group of experts including the American Diabetes Association as an accurate measure of body fat) and waist-to-height ratio, which was found to be more accurate than BMI, according to a 2014 study. (For a complete picture of body composition, however, you’d need a DEXA scan.)

“Clothes, mirrors and pictures don’t lie,” Wadia says. “The weighing scale does.”