I have a new post that explains how and why the body produces ketones, It will help you understand much better the difference between burning fat and having a fat-based metabolism, versus being "in ketosis." It's very long, but I think it's worth reading if you'd really like to understand this -- and if you want to stop freaking out about your ketone levels. (If you click over to that post and want to read only the section that explains the difference between ketosis and running on fat, scroll way down to where it says Ketogenesis: How and Why Do We Make Ketones? Also: Fat Adaptation versus Ketosis.) Happy reading!
If I never hear or read those six words, in that order, ever again, I’ll be one happy individual.
Based on what I come across on low-carb forums, blogs, and videos, there is a lot of confusion about the correct use of urine ketone test strips (which I’ll sometimes refer to as ketostix, since “ketone test strips” is a mouthful, even when you’re only reading). So allow me to ‘splain a little bit about how to interpret these things, and what role they should play—if any—in your low-carb life.
First and foremost is the most important thing you will read in today’s post. (And it is so important that I will likely repeat it in all the posts to follow in this little series. Plus, you can tell it’s important because it’s red, bold, in italics, and all caps, hehheh.)
You can be in ketosis and not lose body fat,
and you can lose body fat without being in ketosis.
Here is an exhaustive, comprehensive list of everything urine ketone test strips tell you:
- There is acetoacetate in your urine.
That’s it. Nothing more. Nada más. Game over. Finito. The fat lady has sung, and Elvis has left the building.
Here is what they do not indicate:
- Your worth as a human being
- The efficacy of your low-carb or ketogenic diet
- What your level of ketosis was an hour ago
- What your level of ketosis will be three hours from now
- Whether a specific food you ate “kicked you out of ketosis” (or, rather, caused there to be less acetoacetate in your urine)
- Whether you are fat-adapted
- Whether you are losing body fat
I’m not saying ketostix are useless for providing any other information besides whether or not there is acetoacetate in your urine. We can certainly use ketostix to speculate about issues other than the presence of acetoacetate, but that’s all it is—speculation, based on your diet, activity levels, stress levels, and more. They provide information, but they do not always provide answers. Are you showing deep purple on your urine test strips but not losing body fat? All that tells you is that being in ketosis doesn’t guarantee fat loss. (Which you already knew, right? Right?!) It doesn’t tell you why you’re not losing fat.
Ketostix are a tool. They give us one measurement, and one measurement only—the approximate concentration of acetoacetate in urine. This single measurement is helpful for hinting at other things we might be interested in, and we can use this acetoacetate indicator to help us arrive at logical conclusions, but we must not let ourselves become beholden to these reagent strips as the end-all and be-all of how we’re doing on a low-carb diet. They’re good, but they ain’t that good, people. (And really, we can say the same thing about blood ketone meters. They tell us only the concentration of beta-hydroxybutyrate [BOHB] in the blood. They tell us nothing about whether we’re losing body fat. And in case you didn’t know, they’re not even really a great indicator of blood glucose levels. There’s a surprising bit of variability in people’s ability to reach and sustain high-ish levels of BOHB. Some people can have a blood glucose in the 90s and still see ketones of >2.0 or 3.0 mmol/L. Others might have blood glucose in the 70s but blood ketones of <1.0 mmol/L. So there is not an automatic correlation between the two, and we can’t necessarily use one as a proxy for the other. We can, however, assume that blood glucose is relatively low if BOHB and acetoacetate are elevated even slightly. BG might not be as low as the 70s, but it’s unlikely to be, say, 130 mg/dL)
There’s a lot to cover on this. (So much, in fact, that I ended up having to break this up into 3 parts. I seem to be physically unable to write anything short.) It’s a bit overwhelming, so let’s just ease into things, and little by little, we’ll get to all of it.
Probably the single most important thing to clear up first is:
Being “in ketosis”
versus being fat-adapted
They are not the same thing. You can have one without the other.
Let’s talk about the simpler of the two first: being “in ketosis.” (I’m going to stop using the quotes now, but you can picture me making the little marks with my fingers every time you see that phrase.) Being in a ketogenic state means that you are breaking down fatty acids at a fairly decent rate, and some of them are being converted into acetoacetate, acetone, and beta-hydroxybutyrate. For those of you who follow low-carb or ketogenic diets, think back to when you first began your low-carb lifestyle. If you jumped in with both feet and went low-carb quickly, rather than making a gradual transition, you likely experienced the “induction flu” or “keto flu” – pounding headache, dizziness, nausea, and some other fun stuff. This is what happens when you are in ketosis but not fat-adapted. Your body is deprived of the copious amounts of carbohydrate it’s accustomed to, and your insulin levels have fallen low enough that you are beginning to break down fats for fuel instead of that endless stream of glucose. However, because it’s only been a couple of days, your body has not yet fully ramped up the enzymes and mitochondrial machinery required to properly and effectively utilize those fatty acids and ketones. So you’re in this hellish limbo we call the induction flu. Your body is producing ketones, but it’s not using them (or fatty acids) very well just yet. (It is still wanting to use glucose. Glycolytic enzymes are going crazy looking for—but not finding—glucose.) This is probably the simplest example I can give of being in ketosis but not being fat-adapted.
We could probably say the same thing about the use of exogenous ketones in an individual who is not following a low-carb diet. Their urine (and blood) would indicate that they are in ketosis, but they don’t have the physiologic machinery in place to keep that ketosis going after the exogenous amount has been metabolized, never mind having their bodies fueled primarily by fat. The state of ketosis induced by exogenous sources is entirely temporary and has nothing to do with the processes the body uses to generate ketones naturally, not to mention ramping up the enzymes and metabolic pathways that make someone a "fat-burner." (I'm not saying exogenous ketones have no role at all in metabolic therapies. I believe they do, but that's a subject for another time. Or maybe I'll see you at this conference!)
Now, let’s look at the other side of this.
You can be fat-adapted without being in ketosis. I know for a fact people can be fat-adapted but not in ketosis because I have personally experienced this many times. In fact, I would say this is my default state most of the time: fat-adapted, but not in ketosis. I follow a low-carb diet, but I’m not always at ketogenic levels of carbohydrate intake, and some days I probably consume enough protein that I wouldn’t see a noticeable change on the ketostix. My carbohydrate intake and resultant insulin levels are low enough to allow my body to be fueled primarily by fat, but my carbohydrate intake is not so low as to have excess acetoacetate perpetually registering in my urine.
Here’s how I gauge my fat-adaptation:
- I can comfortably go several hours without eating and feel no hypoglycemic effects whatsoever
- I have good, steady physical energy levels
- My mind is sharp and my thinking clear
- When I do finally start feeling some hunger pangs, I am just that—hungry, rather than hangry. I will seek a protein- and fat-rich meal, and have no desire to jump head-first into a half-gallon of ice cream or consume a cheese danish. (One of my former favorites, waaaay back in the pre-low-carb days.) I have no interest in sweets or starch. I genuinely want something high in fat and protein—something like a burger, a fatty pork chop, sausages, etc. But if I were to pee on a ketostick, there would be no indication of ketones.
The most striking difference I notice when I am in a more deeply ketogenic state, versus just generally running on fat, is my MOOD. I am quite the gloomy Gus, the negative Nancy, the Debbie Downer, and all those other glass-is-half-empty people. (If you follow me on Twitter, you’ve seen this in action a time or three.) My natural state is one of almost crippling pessimism, self-doubt, and self-loathing. But something rather magical happens to my emotional outlook when my ketones are higher. It’s like someone flips a switch on my spirit, and suddenly I feel like I can accomplish anything—and more, that I am worthy of accomplishing more, and that I deserve to have a happy life. Since this is so different from my normal state of mind, this is basically my non-mathematical way of “knowing” I’m in ketosis. I don’t have to check; I can feel it. But sometimes I do check, if only to corroborate what I already know, and the test strips typically confirm that I’m keto-ing pretty hard.
Okay. Sorry for that little tangent into the dark recesses of my mind. My point is, there is a difference between being fat-adapted and being in ketosis. Maintaining a perpetual state of ketosis (especially deep-ish ketosis) may be particularly beneficial for certain conditions, such as cancer, Alzheimer’s, multiple sclerosis, epilepsy, and other neurological & neurodegenerative conditions. But as many of us know quite well, ketosis doesn’t guarantee fat loss. For fat loss, it is far more important to be fat-adapted than to shoot for high ketones all the time. This obsession with chasing ketones for the sake of bragging about them on social media has got to go. I feel like we’re getting to a point now of blood glucose & ketone “shaming”—whose are the lowest and highest, respectively. And if your blood ketones aren’t at 2.0+, or your A1c is above 4.8, you’re “doing it wrong.”
stuff like this makes me want to quit this industry altogether. It’s
*Continue to part 2 in this series: http://www.tuitnutrition.com/2016/01/dont-be-a-ketard2.html
Remember: Amy Berger, M.S., NTP, 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.