Recommendations for methods of checking ketosis?


It looks like it has been a while since this subject was actively discussed, so I’m bringing it up as a fresh topic.
I’ve eaten a ketogenic diet for about two years. During that time, however, I’ve judged whether I was or wasn’t generally in ketosis simply by differences in how I felt and looked. And I’m wondering what some of you might think about whether I should test, and if so, how often and in what way?
Any takers?

(Polly) #2

What might the benefits of testing be?

The old trope is if you are eating below 20g carbohydrates per day and still breathing then you will be in ketosis.

In the early days of ketosis some people who test show higher levels of blood ketones than in people who have adapted.

So I come back to my question. If you have been doing this for a good while what would be the benefit of testing?


@Polly1 I’m not yet convinced there are benefits (thus why I haven’t yet tested) but I’m interested in knowing to what degree other ketoers feel there are – or aren’t – benefits, and why they have adopted the stance they have adopted!
Potential benefits I can see would include finding my own personal ideal carb level, or perhaps my carb breakpoint at which I would slip out of ketosis. Like the careful measuring I did initially, it strikes me as perhaps being beneficial to test for a while just to get the data and learn from it, but from there on in being able to relax and trust the knowledge gained.
And I admit that sometimes I wonder if I’m kidding myself because I doubt I DO manage 20g a day, even if I know I eat very minimal carbs. Being accountable to myself strikes me as good rather than bad?

(Allie) #4

Best test.
Numbers mean nothing really.

(Old Baconian) #5

I began this way of eating, because I was pre-diabetic—or an undiagnosed diabetic, if you believe the late Dr. Joseph Kraft. I’ve never measured my ketones, nor have I ever counted calories. But I did lose 25-30% of my body weight effortlessly, and my blood pressure, pulse rate, and blood work all returned to normal within twelve months. Going by the way I feel and look is now second nature. I can tell I’m in ketosis by how my mouth feels when I wake up, and by the absence of arthritis and certain skin conditions.

I know that many people on these forums find it reassuring or satisfying to measure everything they can, and it seems this is necessary to them. I, however, would never have been able to embark on this way of eating if it had involved calorie-counting or other measuring. I even had to give up weighing myself, because it messed too much with my mind. It’s not as though our ancestors went around with scales and CGM’s while hunting mastodons, and yet they somehow managed, so I figure I can, too.

(Bob M) #6

You will never be able to find that. I have taken thousands of samples, breath, blood, urine ketones; CGM; pin-prick blood sugar; etc. I could never figure out anything. Really, nothing. Does protein affect ketosis? No idea. Every time I thought it did, I’d then find a test where it did not.

And, the longer you’re in ketosis, the lower your ketones will be in general. At least that’s the way it was for me. I stopped blood testing when every morning was 0.1-0.2 mmol/l by blood.

Further, consider this:


This is from continuous ketone sensors in a single person. Here’s the study:

I have no idea what this person ate, but if this is really what blood ketones look like in other folk, there’s no way to take pin-prick ketones and find out anything. You’d have to take them every 15 minutes or 30 minutes, and even then, you’d have no idea what happened.


Hey @PaulL, this is all very encouraging as that’s my leaning, too. The comment about how your mouth feels in the morning is a new thought to me, however. Would you mind elaborating a bit?


@ctviggen, okay, I’m halfway to giving up the idea already! Certainly if the results of measuring aren’t super clear with a single easy (and inexpensive if possible) test, I can’t be bothered. And of course there would presumably be a number of variables to account for.
This is so helpful, guys. Nice to get reassurance that my lazy keto method isn’t really all that bad after all. At least no convincing arguments on the other side yet!

(Robin) #9

If you have been at this for almost 2 years, you probably already know what you’re doing… what works and what doesn’t.

I’ve never tested. I just do everything I can and trust. My body is quite happy and so am I. If I were to test now, I don’t know what I would gain except perhaps something new to worry about. Also, I’ve heard those readings can fluctuate, just like the scales… for no apparent reason.

You haven’t yet received input from someone who tests on a regular basis. You will. Then you can decide what sounds like a fit for you. There is no right or wrong, just different approaches and mindsets. Either way, you’ve obviously got this.

(Bob M) #10

I should say that there could be reasons to test. For instance, if you’re one of those people who are clearer-headed when your ketones are higher, testing could help you figure that out. It can also be reassuring to know you’re in ketosis.

And I always wanted to do a test before and after eating a lot of carbs (such as I will at Thanksgiving) to see how fast I get back into ketosis. Or even if I don’t get out of ketosis. That would be interesting. (I have some tests that indicate I get back into ketosis quickly, but I’ve never tried a very scientific test; I just happened to be testing.)

(Jane) #11

I have the older Keto Mojo I can’t get strips for anymore, so when I use up what I have I won’t test anymore.

I got it about 6 months into keto eating out of curiosity and it was fun for a while, but as far as useful info - nope. I certainly didn’t change what I was eating based on the data. Now I only test when I am doing extended fasting - again just for grins.


I would also be aware of the potential psychological impacts of testing, especially if you have a history of dieting or disordered eating.

When I first started eating keto, I would sometimes have very “good” days but the test strips would show minimal ketones - likewise I would have “bad” days and the levels would be much higher. Either way it often left me feeling confused and bad about myself, and could quickly destroy the positive feelings of having stuck to my eating plan. It is like the scale in that way, and perhaps equally irrelevant. So if you are someone who is vulnerable to these kinds of insecurities and can easily lose confidence, be careful about giving too much power to these kinds of numbers, and develop your own metrics for success that are meaningful to you and provide lots of validation of positive habits.

(Eric) #13

My take would be that if your really curious, go ahead and test yourself. I would recommend blood or breath because the pee strips become a lot less reliable the longer you have been on Keto. Since the blood meters aren’t exactly cheap, you may want to balance that with how curious you are. The pee strips are definitely cheaper and last time I tested I did get some color change, barely, so at least I know they still worked.

When I started 5 months ago I tested myself daily on the strips and then got a Keto-Mojo and tested myself daily and sometimes 2-3 times a day. Ultimately all I got out of it was validation that staying under 20g of carbs was doing what was advertised. I was in ketosis. Now, I hardly ever test and haven’t for the last 2 months or so. I may check-in out of curiosity but I no longer feel the need to see what my score is. I am probably more curious about the state of my blood glucose reading than my ketones. Hopefully some of this is helpful.

(Robin) #14

Yes! scales and testers lead to head games for me. No thanks.

(Doug) #15

I never thought of testing ketones, but it would be cool to know, just for the interest of it, if nothing else.

IMO blood tests are the only way to go - urine and breath automatically are compromised by showing what is waste, on the way out of the body - doesn’t tell you what’s going on inside.


Zero! Checking ketones is a complete waste of time and money. If you’re been eating keto for 2 years, not eating the carbs and still alive… you’re in ketosis!

I got sucked into that crap years ago, pee strips, blood testing, ketonix, all a complete waste of money, your ketone levels aren’t connected to speed of fat loss which is why most want to test. If you’re not managing a medical condition that you’re replacing medications with keto… why bother?


@robintemplin I think I know what I’m doing, but obviously I do have just a tiny bit of gnawing doubt!


@ctviggen yes, it would be those sorts of situations – after a holiday binge, or even just after a wee bit of overindulgence. Suppose alternatively as a rule I could just fast afterwards. I guess I’m wondering if without testing I’d feel any difference if I were to ‘fall out of’ ketosis. @PaulL mentioned a different feeling in his mouth. Hoping he comes back to give more information on that.


@lfod14 I don’t mind wasting a bit of time if I’m convinced testing is worthwhile, but I’d prefer not to waste money on equipment I’d soon stop using. Nope, not managing a medical condition of any kind – just got into keto knowing how I didn’t want to head toward diabetes (and wanting to lose some weight).


@Camellia I have no history of any sort of eating disorders, however, I can see how measuring ketones could quickly become a compulsion. Although I’ve never been much of a weigh-er either prefering to judge instead by how my clothes fit, if and when I have dieted, I quickly start to pay a wee bit too much attention to the morning weigh-in! Thanks for the reminder about this aspect.