I've been paleo for about 2 months. I am very low carb. I bought some ketostix about a week ago just to check. I am a little suprised that I have negative results. I was even negative or trace amount maybe after a 24 hr fast. I am positive I am in ketosis through my breath, but I find it odd that there is negative for urine. Is there any other way to test for ketosis. Maybe I'm using the wrong type of ketostix since it says for In Vitro urine testing only. I may have had trace amount of 0.5 mmol/L as per the colour chart, but nowhere near what I was expectiing.
IIRC, ketostix will only show if you're excreting ketones. If you're burning most of them, they may not register very high. They would have shown more right after you switched than they do now that you're used to it.
I could be completely wrong, and either way why does it even matter what they say?
Oh that is not unusual at all. Everyone tests positive initially. However, once your body becomes adept at using fat for fuel more efficiently it also uses the ketone bodies for energy too. When the "brain fog" from the initial week or so ends...it's because your brain is using ketones for energy in the absence of excess glucose.
And I see that others have already given about the same answer... :)
Seconding Daniel Smith, by adding: ketonuria does not equal ketosis. Also, ketonuria => ketosis, but ~ ketosis => ketonuria. I.e., ketonuria implies ketosis but ketosis doesn't imply ketonuria. You can be in ketosis without spilling significant ketones in your urine, but you can't be spilling significant ketones in your urine without being in ketosis.
Ketostix aren't the end-all-be-all for being in ketosis. If you feel that you are, you probably are. Ketostix results can be altered by an array of things; most likely you're drinking a lot of water, and that has diluted your urine so much the ketostix won't read a dense amount of ketones. If you're losing weight and feeling good, I wouldn't worry to much about ketostix results.
Kestostix measure ketonuria, or the presence of ketones in the urine. As others have written, if you are using all your ketones for fuel, then excess ketones are not going to be excreted into your urine. So it's possible to be in ketosis without it showing up in a urine test. I suspect I am like you. I can go lo carb for days, close to zero carb, and the color of the ketostix doesn't even budge. But I get a lot of exercise and am probably running a calorie defecit during those extremely lo carb periods, so I'm probably burning all the avalable ketones for fuel.
Are you taking aspirin? Aspirin is one of the many factors that influence false ketone response. Diluted urine can. Make sure 1st morning urine is used and then don't forget to flush. Sulfhydryl drugs, including captopril, can produce a false positive ketone. TOM or "time of month" can give you false readings. Its not all in your head. On a more positive note, Attorneys are more often challenging the results of breathalyzer tests. Among some of the complaints are that if the machine is not re-calibrated properly, or often, it can give false reads. Health conditions like asthma, ketosis, or diabetes can change the readings on a breathalyzer. Keep this handy for that late night pullover after you party to celebrate your 30 day ketone response. Ha, Ha, one more reason that becoming Diabetic was a gift...
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