Insights into my personal life.

This blog includes the personal details of my experiences as a recently diagnosed Type I diabetic and the impact of that diagnosis on my endurance athletic pursuits.

Please understand that I consider myself to be a work in progress. I am willing to share both my successes and failures, so please do not take my words to be professional dietary or medical advice. This is a blog, this is only a blog. I research my choices carefully, and take my health very seriously. The choices I make are my own, I am doing the best with the resources and support that I have. If you have questions or concerns feel free to comment, but please be constructive and understand that this is my life. I value it dearly.

My goal is to live a happy, healthy and active life where I can balance my internal drive to push my physical limits and the challenge of safely maintaining stability despite the challenges of Type I diabetes.

Wednesday, September 18, 2013

Measuring Ketones

I finally started doing something that I should have done a while ago - measure my ketones.  It's something that I initially thought I was doing by using ketostixs, which are cheap and easy to use.  All you do is pee on a stick, wait 15 seconds and then match a color.  But there's more to it than this.

The method above is quite crude.  It's actually not too far from how they used to measure blood sugars not too long ago.  Measuring anything in the urine can be easily thrown off by hydration levels - and considering that I have a sweat rate measured to be more than twice the standard person, it can really get thrown off. Plus anything measured in the urine is old data if you're really concerned about what going on in the blood.  

And finally - ketostix actually measure Acetoacetate (AcAc), which is only one of the three types of ketones produced by the body.  When I initially began my ketogenic journey I was measuring very high levels on the ketostix, but after a couple of weeks, my ketones barely registered.  This is likely due to the fact that over the first couple of weeks of ketoadaptation, things change.  It seems that initially AcAc is produced, but eventually you start to make a greater proportion of the ketone called beta-hydroxybutyrate (BOHB).  The kidneys also change their ability to filter out or hold in different ketones.  Together this may explain why I wasn't seeing much for ketones in my urine, but judging by my performance I'm rather confident that I was still making them.  

While ketostix measure AcAc, a blood ketone detected such as my newly acquired Precision Xtra measure the blood concentration of BOHB.  BOHB is the ketone that is preferentially used by the muscles.  Much of this info I learned from the Phinney & Volek books "Art & Science of Low Carb..."  I also learned the actually levels that I should be aiming for.  

It appears that there is a physiological curve where ketones are most useful.  Most people produce some level of ketones - pretty sure that less than 0.2mM.  In order to be considered to be benefiting for the physiological benefits of ketosis, a person should be targeting a concentration between 1-5mM with 5mM being the peak of benefit, but then the benefit tapers off beyond that. Ketone levels supposedly aren't as variable as blood sugar levels, but I'm still learning how they vary as an effect of both diet and exercise.

I've been testing for a week now.  My first test was last week after I ran 18 mile over the course of two runs during the day.  That test showed 2.3mM.  Bingo!  Then I continued to test over the course of the week - still running each day - distances ranging from 6 to 12 miles, but each day the ketones in the evening measured less and less.  0.9mM, 0.6mM, and then last night 0.4mM.  

While I'm very relieved that the numbers are on the conservative side, I was concerned that I might be doing something wrong.  I'm able to run for 2-3 hours at a time without carbs, with stable blood sugar and consistent energy (all done at an easy aerobic pace). I'm confident I'm in ketosis - and I feel very good, but 0.4mM is pretty low.  

But then today I got in a 5 hour ride.  Easy pace again, reduced my temp basal to 0.1U/hr and achieved very steady blood sugar numbers ranging from 75 to 90 mg/dL - energy felt fine.  I haven't been spending much time on the bike since I've been focusing on my running lately - so I didn't feel incredibly strong on the bike, but I felt good.  I should could have stopped for more water and perhaps packed some salt, but I managed fine in the cooler weather.  It was just an easy ride - a good opportunity to finally log some miles on the tri bike.

I ate some dinner post-ride since I was hungry.  I'm learning to manage my habit of post ride eating.  I'm still used to the urge to have to eat right when I finish riding, even when I'm not actually hungry.  I have to be careful with what I eat post workout since my insulin levels are much lower than usual, even a small amount of carbs would spike me - I would love to have a nice green juice but even the carbs in that would spike me pretty quickly.  So I found a nice dinner with plenty of fat.  And then I enjoyed a nice cup of home made chicken broth to replace some of my electrolytes.  Feeling good now!

What did the long ride mean for my blood ketones?  3.2mM!  Boom.  From 0.4mM last night up to that.  Now higher isn't always better - their is no benefit to running blood ketones higher than 5mM.  But I'm also nowhere near the levels that would be a concern as far as the dreaded diabetic ketoacidosis, which can be found in the range of 15-20mM.  

I had planned to run afterwords, but I'll save figuring out how to transition from bike to run for another day.  That task is going to have some nuance to it as well.
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