The “rule of 15” is so 15 years ago

If I lived in mmol/L land, my blood sugar would be a diminutive 'two'.

Someone, somewhere, came up with this so-called “rule of fifteen.”  If your blood sugar is low, treat it with a fifteen-carb snack, then patiently watch the second-hand spin ’round the clock fifteen times before testing again.

You have got to be kidding me.  This rule is so flawed, that even the glucose tablet confectioneries don’t make products which comply.  (Speaking of confectioneries, I went to college down the street from Just Born, makers of delicious [I’m told] candies such as Mike & Ike and Marshmallow Peeps.  The place itself looks like a hospital, and it took years to realize what really went on in that building!  Now I hear that Mike and Ike might be splitting up.  So sad.)

Back on topic.  With no individual customization whatsoever, or no evaluation of just how low a person might be, fifteen carbs will always do the trick.  And if it doesn’t. try again.

Well, when my blood sugar hit 36 mg/dl (2.0 mmol/L) last week, I knew 15 carbs wouldn’t do the job.  No way.  Not if I was that low.

So I had four glucose tablets: 16 carbs.  Feeling a bit unsatisfied and unconvinced by the tropically-flavored chalk, I also had an orange.  And a handful of almonds (because they were there, and I really like almonds), and some raisins.  Finally, I washed it all down with a Diet Coke.  Because even if I’m indulging on carbs (whether treating or just cheating), my commitment to Diet Coke is unbreakable.

I spent the rest of the evening rage-bolusing against the 300 milligrams of glucose coursing through every deciliter of my bloodstream.  I knew it would happen, but I just didn’t want to drop down to a 35.

(By the way, that 36 came after vacuuming my car interior, because cleaning is almost always the first sign of hypoglycemia.  Despite the slight dizziness and sweat dripping down my back, the absense of a down-arrow on my pump/CGM made me believe everything was alright.  As I discussed on Monday, that was not the case.)

What should I have done?  Well, that little back box with the tiny motor and the Energizer battery that stays clipped to my belt has a whole bunch of ratios programmed into its Bolus Wizard.  Carb ratio: 1 unit of insulin is needed for 9 carbs of food.  Sensitivity: 1 unit of insulin will lower my BG by 60 mg/dl.  Therefore, 9 carbs will yield a 60 mg/dl.  Factor the denominator and carry the one, and you learn that 1 carb should give me a 6.6 mg/dl bump.

Thank you for these words of wisdom!

No way in hell am I going to do this math when my BG is normal, much less when it’s 36.  But my pump could’ve done that, it’s really good at math.  It could’ve told me that, to get back to normal range, 10 carbs would do the trick [hard to believe, but the numbers don’t lie].  But no, it just told me that it wouldn’t be a good idea to bolus right now, and that I should do something about my low sugar.  Gee, thanks.

Now I know why PWDs always, always, ALWAYS overtreat lows.  It’s that damned Rule of Fifteen.  It must harken back to the days of Ye Olde Exchange Diet, where every starch and fruit exchange were measured in intervals of 15, and everyone’s suggested insulin needs were 1 unit per exchange/15 carbs.