Ketone testing

(Mark McDole) #1

Hi everyone! I started Keto on November 30, 2020. I just tested my blood ketone level for the first time and it came back as 0.0. I am really confused since I have been on this diet for 15 days. I will give some background information and if anyone could let me know if this is possible I would appreciate it.
Before I started the Keto diet I kept track of my carbs for 5 days and I was averaging just over 900 grams each day (not sure how crazy this is, but it is true). I am 50 years old, I am 6ft tall and weigh 216 lbs. I work out with weights. I can bench 300 pounds, I am giving this information not to brag, but to let the reader know that (1) I have been lifting for a while, (2) I am not using light weights as cardio, and (3) because of muscle my body looks different then someone with my weight and height who has never worked out. I would not mind losing 10 pounds but my main reason for going on Keto is for better health. I am using a calorie count app that I pay for. During this time I have averaged about 50 carbs and 25 net carbs. My daily calorie intake has has averaged around 1,600. I lift weights 5 days a week. Since I only do one body part each day, my workouts only average about 30 minutes. The only meds I take are Lipitor and a daily multi vitamin. I was very disappointed when my 15 days of hard work came back as 0.0! Does anyone know what I may be doing wrong?


(Bob M) #2

Are you using the urine strips? Those can be deceiving. Urine strips are problematic, because they also rely in part on hydration. Drink more water, get a lower value.

For any ketone measurements, try taking them multiple times per day. My ketones are lowest in the morning and highest in the evening.

Also, if you’re lifting that much, it could take a while (probably longer than a month) to transition to where your workouts are good. How are your workouts now?

(Mark McDole) #3

Thanks for responding. I am using the blood testing strips. My workouts are good. I have not felt any weaker.
Does it really not matter how high your total carbs are as long as your net carbs are very low and your caloric intake is reasonable?

(Bob M) #4

That’s a difficult question to answer. Some people believe in only total carbs, others are fine with net carbs. But since you’re lifting a lot, exercise also factors into this: the more you exercise, the more you can “use up” carbs. I believe most of the studies have been done on endurance athletes, though, not lifters.

So, as long as you keep your carbs “low” (where this exact amount is difficult to find, especially if you’re exercising), you should be in ketosis. It’s just a matter of time, really.

(Mark McDole) #5

I just re-tested my blood and this time it came back at 1.6. I think this is better.
The monitor is brand new so the 1st time I used it maybe it was off. When should I check it again? Do you check your blood every day, twice a week, or once a week?


(Bacon by any other name would taste just as great.) #6

First, most people who measure tend to do it once a day. Don’t stress over the readings, since they will vary. You probably had a bad strip, the time you mention in your first post. Just pick a time of day and be consistent. The cleanliness of the finger you prick for a blood measurement can affect the reading. A lot of people don’t measure ketones at all, since if our carbohydrate intake is low enough and we are still breathing in and out, our liver has to be making ketones.

Now, as for whether to count total or net carb intake, that is something you are going to have to determine for yourself. The idea behind net intake is that fibre is indigestible and therefore need not be considered. However, the experts vary.

On the Ketogenic Forums, we recommend an upper limit of 20 g/day, but leave it up to you whether to count net or total. Dr. Stephen Phinney at Virta Health gives patients a limit of 50 g/day total, in the hope (as he has stated) that their net intake will be under 20 g. Dr. Eric Westman gives his patients a strict limit of 20 g total and said in at least one lecture I’ve watched that there is evidence to suggest that fibre may not be as indigestible as we have heretofore thought. Some of the old weight-loss diets before the current nutritional dogma took hold told people to avoid sugar, grains, and starches, but allowed unlimited amounts of leafy greens, etc. The diet that worked for William Banting in the 1850’s (described in his Letter on Corpulence) would look a bit high-carb today, but it worked for him.

The key point, no matter what the diet, is to lower carbohydrate intake sufficiently to avoid a chronically elevated serum insulin level, since that way, we are avoiding damage from hyperglycaemia and hyperinsulinaemia. Measuring ketones is an indirect way of ensuring that insulin is low, since elevated serum insulin inhibits ketogenesis in the liver. But this way of eating is not solely about avoiding elevated insulin, it is also about the hormonal and nutritional benefits of the three ketone bodies (acetone, acetoacetate, and β-hydroxybutyrate). They not only serve as useful alternative fuels to various organs (especially the brain and the heart), but they also have epigenetic effects that promote health and well-being.

ETA: Caloric intake is less relevant when we give the body the proper food, since the hormonal response determines what happens with that food. The metabolism speeds up, under the right circumstances, and although a ketogenic diet involves eating more fat than the standard diet does, increased fatty-acid metabolism results in more fat-burning, not less, particularly when we give our body enough food for it to feel safe shedding some of its reserves. The idea is not to restrict calories intentionally, but to let our appetite guide us to how much to eat. When we have excess fat to shed, the caloric restriction will occur naturally, as the appetite hormones do their proper job (since insulin is no longer high enough to interfere).

(Bob M) #7

You’re asking the wrong person that question. :wink: I have several engineering degrees and have been a scientist since as early as I can remember. I have thousands of samples in a spreadsheet. The samples include blood glucose (5 meters), ketones (4 blood ketone meters, 1 breath ketone meter, urine strips), etc. I have tried to test all kinds of theories: what does protein do to ketones? fat? carbs?

After a while, I gave up testing, when answers to those questions were difficult to find.

I think for most people, maybe once a day or less isn’t bad. I’d also test in the evening, as the morning values can be low. Or, I should qualify this with “my morning blood ketone values are low”. I gave up on urine testing when both blood and breath showed ketosis, but urine did not.

But that was after I had been in ketosis for a long time. Initially, urine strips work fairly well. Some people believe they work even for those of us doing this for a while. I have not retested this, though.

(Bacon by any other name would taste just as great.) #8

As far as I can tell from reading forum posts, they continue to work for some people and stop working for others. Lots of individual variation.

(Bob M) #9

That could be true. I started with urine strips, and they did work for a while, but then I went to breath and blood. I circled back and did a test with urine strips, and they weren’t great.

Here’s one. After the time is blood ketones (Precision Xtra), then breath (ketonix), then urine, then blood sugar (forget which meter, though it was pin-prick).


At 5:08 am on Tuesday, I’m in ketosis, 0.4 mmol/l for blood, 73 for ketonix (which, by the way, I never get close to, now that 4 years have passed – I’m lucky to get into the 30s!), but a negative urine. But the Wednesday morning test was okay for the urine.

(Bacon by any other name would taste just as great.) #10

Well, as we know, the urine strips were invented to provide a rough early warning to Type I diabetics to get to the hospital if their serum ketones and glucose start to get out of control. They are certainly not intended to provide a high degree of accuracy, but given their primary function, they are adequate to the task. That they give us some indication of our degree of ketosis is merely an added bonus.