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ph, mention of blood, math/chemistry (possibly incorrect)

When you think about it, blood glucose meters need to be shockingly precise. Let's take a real-world example to illustrate this.

This morning, my glucose levels were 6.7mmol/L. What does that mean? Let me dust off my high school chemistry and bust out a calculator.

The internet tells me that glucose has a chemical composition of C6H12O6, which would give 1mmol of glucose a mass of about 180mg (0.18 grams).

A reading of 6.7mmol/L means that in a litre of blood, there would only be about 1.2 grams of glucose.

For perspective, a litre of water is 1000g. I don't off hand know the density of blood, but I imagine it's not too far off.

My meter was able to tell this from a drop of blood.

That's pretty wild. Can someone check my math on this?

in reply to Jonathan Lamothe

ph, mention of blood, math/chemistry (possibly incorrect)
Your math is good but would you redo you calculations in ounces and gallons so us Americans can make sense of them? 😜
in reply to PerryM ✅

ph, mention of blood, math/chemistry (possibly incorrect)

@PerryM ✅ I don't understand Freedom Units, but I tried to put everything in the same unit (grams) to give an idea of the sense of scale. My main takeaway is that the glucose measurement makes up somewhere in the ballpark of 0.1% by mass. The fact that it's possible to get that precise a reading from a single drop of blood is downright bananas.

Edit: 0.1%, not 1%. 1% would probably be lethal.

in reply to Jonathan Lamothe

ph, mention of blood, math/chemistry (possibly incorrect)

Jon, I was "pulling your chain". Your math is perfect and your amazement logical.

Not questioning the accuracy is nearly the same as not questioning the building an ARK big enough to hold 2 of every animal on earth and feeding them and what comes next and even getting all of them on the Ark without DHL!

in reply to Jonathan Lamothe

ph, mention of blood, math/chemistry (possibly incorrect)
My guess is that you never worked for Elizabeth Holmes and Theranos either!

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