How to test blood ketones for reaction?

(Candra ) #1

I want to test my blood ketones after I eat something to see if it kicks me out of ketosis. How soon after I eat the item should I test?

#2

When testing blood glucose, I usually test just before (T0), 30 minutes (T30), 60 minutes (T60) and 90 minutes (T90), but ketone strips are more expensive, so I usually do T0 and T60.

(Tim Scudder) #3

Candra, I’ve found that I have to wait many hours before I see a true reaction. For example, if I have a carb-refeed meal @ dinner (I do carbs like rice/sweet-potato once every few weeks), I won’t see my ketones drop much until at least the next morning (and I can usually feel that I’m out of Ketosis). My theory/hypothesis (based on data like the chart below and the few times I’ve dropped below 0.5 ml/mol over the past year since I’ve measured BHB with the Precision Xtra), is that the ketones measured in your blood are the “surplus” ketones your body has not consumed - it’s not what your cells are consuming but what’s left over - so if your cells shift to consume glucose, this level won’t drop precipitously after a carb meal. If you eat enough carbs to push your blood sugar high (assuming your body has filled it’s glycogen stores), your body is going to focus on utilizing the glucose first (glucose is toxic at high levels), leaving your ketone levels somewhat unchanged, but signaling to your liver to slowly reduce ketone production. As you can see in the chart below, it slowly lowers over a few days. I’ve personally found that (once keto adapted) I can have a high carb meal every few weeks and regain my ketone levels the next day after skipping a meal and having a low carb lunch/dinner…hope that helps.

https://thequantifiedbody.net/wp-content/uploads/2016/02/10daywaterfast-ketones-glucose.png

Progress on long stall broken -ketones up-weight still going down
(Candra ) #4

Thank you @BillJay and @Tim_Scudder …

I did an n=1 on an item today to see what my reaction was to it. I am not sure I quite know how to interpret the results.

Blood Glucose results after eating “X”

T0 = 81
T30 = 96
T60 = 111
T90 = 110
T120 = 100

My questions are: How much of a rise in BG constitutes a spike? And how much of a spike will stop ketosis?

I did not do my blood ketone levels because I just can’t afford it. (I bought 10 three days ago for $30 and on a limited income that is a chunk of change!)

Note: My blood ketone level yesterday was 1.2 after a 19 hr fast but was at .7 (I had a few berries last night) this morning at 10 am. Also, my BG level was unusually low this morning probably because of fasting yesterday. I usually run 110-112.

Thank you for your help!

(Candra ) #5

Thanks! That is helpful! I decided that I really can’t afford to do a n=1 with blood ketones because it is too cost prohibitive. I will have to stick with BG testing.

#6

Unfortunately BG testing is a poor proxy for inferring ketosis, so there’s no fixed BG level that is the cutoff, but your postprandial numbers don’t look high enough to cause an anti-ketogenic effect, but as we know from Dr. Kraft, it’s more about the insulin and less about the glucose, so if your body is generating a lot of insulin to keep BG at those levels, it could drop you out of ketosis.

Like @Tim_Scudder says, often effects on ketosis can be quite delayed since we’re measuring the circulating ketones and it can take some time for a reduction in ketogenesis to show up as lower BK.

Yeah, those strips are expensive, so you probably won’t be able to infer if foods are kicking you out of ketosis from BG testing, but if you see spikes in BG, it’s a sign that those are foods to avoid.