The following Mark's Daily Apple article was written by Mark Sisson, and is narrated by Tina Lehman.

Stop obsessing over the numbers.

My friend, former co-competitor, business partner, and writing buddy

Brad Kearns had been on a quantified self-kick, tracking biomarkers, testing blood sugar and

ketone levels, and staying abreast of all the various ways we can quantitatively check our progress.

He's months into a ketogenic experiment and had hoped to marry

his subjective impressions to objective measurements to strengthen his intuition and improve his

results. Then, several weeks ago, it all changed. Using the same finger prick sample, he checked

his fasting blood sugar using three separate devices. Same blood

sample, three devices purporting to give accurate readings. You'd think the results would be similar,

if not identical. They weren't. That's not just a few points here or there. That disparity is

well outside standard deviation. The numbers can't be trusted

because which one's right? And if you can't trust the numbers, what's the point of gathering

them? Brad's results were extraordinary, but making any conclusions from the measurement of an

organism's secretions, emissions, and fluids must be tempered with the fact that biology is chaotic.

It isn't clean, neat, or predictable.

If you dig deep enough, it might be predictable, but we don't yet have the technology capable of untangling it.

This isn't just limited to over-the-counter glucose monitors either.

Three other methods are, one, gut biome testing.

The different gut biome sequencing services can provide different results.

One person had about as contradictory a pair of results as you can get from the same sample.

In another case, taking samples from different sections on the same poop gave different bacterial readings.

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