My previous post walked you through 14 non-weight-loss ways to gauge how a ketogenic or low-carb diet is working for you. But what if you do want to lose weight? Sure, lower blood sugar, lower blood pressure, remission of migraines, disappearance of hypoglycemia and brain fog, and total resolution of acid reflux are all pretty great, but what if one of your goals is to see the number on that dastardly scale go down?
There’s nothing wrong with wanting to change the size and shape of your body. But a scale is a terrible way to assess whether you’re accomplishing that. Here are seven reasons not to depend solely on the scale when you’re using keto to change your physique. (Some of these are excerpts from my book, The Stall Slayer. Lots more info in there about using keto/low-carb for fat loss. I also recommend checking out this video I did on reasons to stay off the scale.)
1. Body Weight Fluctuates
It’s important to understand that fat loss is not linear. You don’t lose a little bit every day, steadily, until you magically arrive at your goal weight. If only, right?! There will be bumps and hiccups along the way—slight ups and downs, and days and weeks where the scale doesn’t change at all. This is completely normal, and you have to be mentally prepared for it. Going a few days or even a few weeks without any change on the scale doesn’t mean you’re doing something wrong. It’s your complicated and complex human body being complicated and complex.
Over the course of the months, years, or decades that you gained weight to get to where you are now, it’s unlikely that you gained a couple of ounces steadily every single day until reaching your highest weight. It’s more likely that it came on a bit at a time, stayed steady for a while, then increased a little more, stayed the same for another while, increased a bit more, and so on. The reason you didn’t see it going up a little bit once in a while and then staying the same for weeks or months is because you weren’t getting on the scale every day. So, just like you didn’t gain a little weight every single day in a steady pattern, most of us don’t lose weight every single day in a steady pattern. There’ll be a bit of loss, then some amount of time at a steady weight, then a little bit of loss again, then another period of time at a steady weight, maybe a little bit of weight gain, then some loss again…
Wait a minute. Weight gain? Did I just say weight gain?
Yes. Yes, I did.
Before you freak out, stay with me and look at the images below.
If you are addicted to the scale and weigh yourself every day—maybe even multiple times a day—you will drive yourself completely bonkers leaving your emotions at the mercy of that silly number. But don’t take my word for it. Let’s turn to some serious experts to see what they have to say on this issue:
Here’s an excerpt from The Art and Science of Low Carbohydrate Living, by renowned keto researchers Jeff Volek and Stephen Phinney:
“Don’t Trust the Bathroom Scale With Your Mental Health
We humans are about 2/3 water. Each of us contains about 40 liters (or quarts) of the stuff, and each liter weighs a bit over 2 pounds. Our bodies effectively regulate fluid balance by adjusting urine output and sense of thirst, but this is done within a 2-liter range. Within this range, your body doesn’t really care if it is up to a liter above or below its ideal fluid level.
What this means is that we all live inside a 4-pound-wide grey zone, so that from day to day we fluctuate up or down (i.e., plus or minus) 2 pounds. This happens more or less at random, so with any one weight reading you don’t know where your body is within that fluid range. Your weight can be the same for 3 days in a row, and the next morning you wake up the scale says you’ve ‘gained’ 3 pounds for no apparent reason. For people who weigh themselves frequently, this can be maddening.”
See? I told you!
For the sake of your mental health, I recommend weighing yourself no more often than once a week, and once every two weeks might be even better—if you choose to weigh yourself at all. Some people prefer to weigh themselves daily, and I understand that. They find that it helps keep them accountable and stay on top of things: after all, if you weigh yourself every day, you can catch weight gain in the early stage, before it creeps up very high. It’s easier to course-correct and get back on track when it’s just a little snowball of a couple pounds coming back on as opposed to an all-out avalanche of regaining everything you’d lost and then some.
Overall, though, I don’t recommend weighing yourself every day, so if you’re not doing that, don’t start. If you are a chronic weigher, however, and you want to keep weighing daily, there are some things you need to understand and have at the front of your mind every time you step on the scale. (These also apply to people who weigh themselves only once in a while.)
2. Body Weight Versus Body Fat
I was initially going to title this post “Five Reasons Why the Scale Lies,” or “Five Reasons Not to Trust the Scale,” but both of those would have been inappropriate. With regard to your weight, scales do tell you what you weigh. And unless your scale is wildly inaccurate, you can trust it. But let me emphasize: scales tell you what you weigh. You can trust them to tell you just that: your weight.
Your body weight. Nothing more. A regular ol’ bathroom scale does not know the difference between water, muscle mass, organs, tendons, ligaments, bones, and body fat. It cannot distinguish between any of these. Scales measure one thing and one thing only: the force of Earth’s gravity on your physical body. (That’s what your weight is, technically.) A bioimpedance scale can measure body fat, water weight, and other tissue mass, but if you’re using one that was relatively inexpensive and looks like most regular bathroom scales, I wouldn’t take the results as gospel. Some doctors’ offices and gyms have more reliable (and more expensive) models that will give you more accurate results if you insist on tracking things to this degree. But the bottom line here is, your body weight doesn’t tell you how much body fat you’re carrying.
Why does this matter? Well, you don’t want to lose “weight.” You want to lose fat. (If you know you’re carrying a lot of excess water/fluid, then yeah, you want to lose more than just fat, but for the majority of folks out there, the goal is fat loss, not necessarily weight loss.) When you’re using keto (or any other eating plan) for the purpose of losing body fat, it’s not uncommon for your size and shape to change even when your scale weight stays the same—or even goes up a little! When this happens, your clothing will fit differently. Your waist might be shrinking. If you wear rings, they might be looser. For this reason—changes in body size and shape even when the scale doesn’t budge—a tape measure and your clothing are often better tools than a scale for assessing changes to your body. It’s not unheard of for a woman to go down a dress size even while her scale weight is unchanged. Like Drs. Volek and Phinney said: don’t trust the scale with your mental health.
Don’t go solely by the scale when assessing how keto is working for you. The scale is only one tool among many that can give you information about how your body is changing from this way of eating, and it’s probably the most misleading. Take your measurements once a week or twice a month. Not just your belly, waist, and hips, but also your upper arms, thighs, calves, neck, or anywhere else you’d like, particularly if you’re looking to lose a large amount of fat. (This applies less to those who are already close to their goal weight or shape. These changes will be less noticeable for those people.) Notice how your clothes are fitting. If your size and shape are changing in the direction you want them to, who cares what you weigh?
3. Water Weight
As Volek and Phinney explained, scale weight can fluctuate by as much as 2-4 pounds from day to day, and this does not necessarily reflect a change in body fat. The short list of things that affect weight in the short term—and remember, this is just the short list—includes environmental humidity, sodium intake, exercise, and hormonal changes, particularly for women during the menstrual cycle. (Gotta love those hormones, right ladies?) Not everyone retains water when they consume a lot of sodium (salt), but some people do, and this can affect scale weight. Most people retain a bit of water when it’s humid out, and, surprisingly, when they exercise. Exercise can be helpful for building muscle mass and maintaining fat loss, but in the short term, physical exertion—especially weightlifting or resistance training—can make the muscles hang onto water, causing your scale weight to stay the same or possibly even go up a little. I hope it’s obvious that this not because you gained body fat. It’s just water, and it won’t stay around long. I understand it can be frustrating as all you-know-what when you don’t see your scale weight decrease, or maybe it even increases, but this is why I recommend against weighing every day. An increase in the number on the scale because of physiologically normal water retention does not mean you have gained body fat.
I’ll share another great excerpt from The Art and Science book:
“A Sore Muscle is a Swollen Muscle
Most people think that if they do an intense workout (say 90 minutes of circuit training in a gym) that they should lose weight. And indeed, if you weigh before and right after such a workout, the scale goes down because of sweating and water weight loss. However, if it makes you sore for the next few days don’t be surprised to see the scale go up. That’s because muscle soreness indicates that your muscles are temporarily inflamed, and inflammation causes fluid retention and swelling in that muscle. Once again, don’t let the scale make you crazy. Once the soreness is gone, the swelling is gone, and the scale comes back down to where it’s supposed to be.”
So yeah, in the short term, intense exercise can make your scale weight go up. Does that mean you should quit exercising? Of course not. (The same is true for blood glucose, y’know. Intense workouts raise blood sugar acutely—because they’re supposed to! If your blood sugar goes up during a hard workout, congratulations! Your body is doing exactly what it’s supposed to do. More on this in a future post, because elevated blood sugar on ketogenic diets is a hugely misunderstood topic that definitely needs some mythbusting.)
4. Gaining Good Weight
This might apply more to women than to men, but it’ll apply to some fellas out there, too: If you’ve spent several years (maybe close to your whole life!) restricting calories, over-exercising, undereating, and living on low- and no-fat foods that were high in carbohydrate (things we all thought were “good for us” – granola bars, bran muffins, fat-free yogurt, soy lattes), your body likely lost some very important tissue it couldn’t afford to hold onto when you were pushing yourself to the limits without adequate rest and nutritional replenishment. Now that you’re feeding yourself better foods—good quality proteins and fats—and your body is actually being nourished, you might be rebuilding critical tissue you lost during all the years your body wasn’t getting what it needed.
You could be replacing lost bone mass and muscle mass, or strengthening connective tissue such as tendons and ligaments. This is a good thing, but it might show itself in either no downward movement on the scale, or possibly even a little increase in your weight. Just because the scale isn’t moving, or isn’t moving as quickly as you’d like it to, doesn’t mean good things aren’t happening inside you—things that need to happen if you want to age gracefully and be able to get up out of a chair under your own power when you’re 85, or to not break a hip if you take a fall when you’re 70. Let me say this again for the folks in the back: just because your scale weight isn’t changing doesn’t mean very good, very important things aren’t happening inside you. If you’re gaining weight because you’re restoring muscle or bone mass, why get upset that you’re not losing weight?
As I mentioned in this video, Megan Ramos from The Fasting Method shared an experience with a client who had been doing very well losing weight with a low-carb diet and fasting, but she became downright horrified when, at one point, her scale weight started going up. Well, this seasoned older woman had osteoporosis, and Megan, being the expert that she is, suggested the client get a DEXA scan to get a better idea of her body composition, as opposed to just weight. And guess what? The increased weight was due to an increase in bone mass! Not body fat. This was critically important tissue that this woman needed to gain, and should have been happy to gain, but because all she saw at first was the weight, and not the composition of that weight, she was freaking out instead of celebrating.
And of course, there’s the issue of gaining muscle mass. Muscle mass is probably the most underappreciated contributor to health and longevity. (Watch this video or read this article to find out why. Bottom line: you want to have muscle on your body, and you want to use that muscle and keep it strong.) If you are lifting weights or doing other training to build or strengthen muscle mass, your scale weight might stay the same or go up even though you may be losing body fat, and your shape and size are changing in a favorable way.
The horse is already dead, but let’s beat it some more: your scale weight does not tell the full story of what’s going on inside you.
5. Menstrual Cycle
Ladies, you have got to stop driving yourselves crazy over fluctuations of only a couple pounds from day to day when you’re of reproductive age and are riding the hormone rollercoaster. Many women report that keto helps tremendously with PMS symptoms, and that their mood swings, irritability, cravings, breast tenderness, cramps, skin breakouts, and other issues are massively improved since going keto. But this isn’t true for everyone, and a little bit of bloating around “that time” is totally normal, keto or not. I can’t stress this enough: remember that it’s just water and it’ll be gone as soon as Aunt Flo leaves town. If you’re retaining water around your period, this is not body fat gain, so why not just stay off the d*mn scale altogether and save yourself the emotional stress?
6. Problems with Having a “Goal Weight.”
Did you start keto with a goal weight in mind? A precise number you were looking to get to? What if you get there and you’re still unhappy with yourself? Or what if you don’t get all the way there but you’re thrilled with the point you did get to? (This applies to aiming for a specific body fat percentage, too.) Because of these possibilities—reaching your goal weight or body fat percentage and still being unhappy with your appearance, or being totally satisfied with your physique even if you’re not at whatever goal number you set for yourself—I suggest not having a goal weight at all. Goals, yes. A goal weight, no. Remember what I said about body fat, water, muscle mass, bones, and all the other stuff that figures into scale weight: your weight doesn’t tell you much about how you look, and certainly not a whole lot about how healthy you are.
Don’t wait for a number on a scale or a body scan to tell you you’ve “arrived” when you’ve already been there for a while.
7. Your Weight Does Not Determine Your Value as a Human
Allow me to issue a personal plea to those who insist on weighing themselves every day: don’t use the scale as the judge of whether you are a good, lovable, worthy human being. Those qualities have nothing—nothing—to do with your size, shape, or weight. (They also have nothing to do with how “keto” you are, how many carbs you’re eating, or how “clean” your diet is.) Do not let the number you see on that blasted scale determine whether you have a good or bad day, what kind of mood you’ll be in, or whether you deserve to have a happy, fulfilling life. If the scale has this amount of power over you, take that power back. Take a sledgehammer to your scale and show it who’s boss. (Or at the very least, stash it away out of sight, at the back of a very deep, dark closet, where it belongs, and forget about it for a while.)
Like I said, I recommend weighing yourself weekly rather than daily. Or not at all! If you do weigh yourself daily for accountability, please, please remember what you’ve read in this post. Understand that fluctuations in your weight are normal. Don’t let these numbers define your mood for the day or your worth as a human being.
But what if nothing is changing? What if your weight, size, and shape have all stayed the same for a while?
A frustrating place to be! Here are two suggestions for addressing this and then I’ll leave you with some positive reinforcement.
One: Read this article I wrote on how to stay motivated during a weight loss stall. (I used “weight loss” in the title because for better or worse, that’s a bigger search hit than “fat loss.”)
Two: Check out my book, The Stall Slayer, which I wrote for exactly this purpose: helping people break fat loss stalls on keto.
And now for the positive reinforcement. Keep in mind that even if your weight and measurements aren’t changing, good things are happening on the inside. As long as your carbs are low, which keeps your blood sugar and insulin on the low side, you’re reaping the cardiometabolic benefits of this way of eating. You can have lower triglycerides, higher HDL, lower inflammation, better energy levels, less acid reflux, less joint pain, clearer skin, fewer cravings, sharper thinking, more stable moods, and less insatiable hunger even if you haven’t lost any weight. Researchers have shown that the cardiovascular and metabolic benefits of carbohydrate restriction occur even in the absence of significant fat loss. This means that people get healthier on keto even when they don’t lose weight. In my previous post, I presented 14 signs that keto is doing good things for you that are totally unrelated to fat loss. I included a bonus 15th thing, and frankly, I probably could have included 20 things if I wanted to. I know you want to lose fat. I know you do. But it’s not always about that. Repeat: it’s not always about that.
Stay the course and trust the process. If you’re eating keto, you’re getting healthier on the inside, even if you don’t see it on the outside just yet.
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Disclaimer: Amy Berger, MS, CNS, is not a physician and Tuit Nutrition, LLC, is not a medical practice. The information contained on this site is not intended to diagnose, treat, cure, or prevent any medical condition and is not to be used as a substitute for the care and guidance of a physician. Links in this post and all others may direct you to amazon.com, where I will receive a small amount of the purchase price of any items you buy through my affiliate links.