When will US switch bG units from mg/dl to mM?

I hope soon.

Pros? millimolar is more logical, used in Europe and elsewhere, easier to work with, used in research labs everywhere at the bench-level, the publication standard in peer-reviewed material in biochemistry and related fields, and ultimately better than milligrams per deciliter to express bG.

Cons? The US adopted the obsolete system in common practice and people are lazy to change from what they are familiar with.

How to convert? It's easy. Just remember the number 18 as a conversion factor until you get used to thinking of the new unit. It's this simple: 18 mg/dl = 1mM.

What's your opinion on a US switch-over? What say you? Make your case here.


The euglycemic range is typically 3.9 - 10 mM.
(same as 70 - 180 mg/dl)

The desired clinical clustering of bG data is around 6.0 to 6.5 mM.
(same as 108 - 117 mg/dl)

Hypoglycemia is defined as bG <3.9 mM. (same as <70 mg/dl)

Severe Hypoglycemia is commonly described as bG <2.5 mM. (same as <45 mg/dl)

The range of bG meters is 1.1 to 33.3 mM which pretty much covers all values one is likely to encounter. (same as 19.9 to 599 mg/dl)

My own morning f(bG) meter reading today was 7.0 mM. (same as 126 mg/dl)

I like triple digit measurements. 119 to me is different than 111 and I'm not enamored of the trails of infinite decimals generated by 18.

Acid,This non-mathmetician imagines a "formula for pi" result on the pump,continuing around the earth several times; as it computes my dosages needed for whatever units are compatable to 1/2 cup of diet cranberry juice. I am not "enamored " with the change, either.
God bless,

Europe is not using mmol/L but the majority of European countries are. Germany for example is using both systems because in the GDR mmol/L was standard.

However there are good reasons to not switch to mmol/L:

a) the mg/dl scale gives small differences more weight. For mmol/L some of the importance is in the decimal places. Psychologically people do not give much importance to small numbers. 8.8 does not look high compared to 6.6. But the small difference of 2.2 it is already hurting the kidneys. In comparison 160 mg/dl is clearly 40 mg/dl higher than 120 mg/dl.

b) more math for corrections: as a general standard it is assumed that one unit of insulin will decrease the glucose by 30 mg/dl. In mmol/L terms this is 1.66 and simplified this is just 1.6. Now the calculations with these numbers are more complicated. Example: you have 190 and want to calculate the dosage for a correction to 120:

(190 - 120) / 30

(10.5 - 6.6) / 1.6

c) I do not see any advantage to switch to the mmol/L metric. It is just data and for scientific evaluations this data can be converted easily.

We use mmol/l but the hospitals use mg/dl, even the blood services uses mg/dl, probably a standard that everyone understands in their setting, so be it, it’s just data!

I think I will stick with mg/dL, it's the clinical standard for the US and if my pump and meters where uploading data as mmol/l it would be useless when my clinic uploaded it for use with their programs. And then there is also the life's to short don't sweat the small stuff...;-)

But I would like to have a cool green bird dog like that...if he could talk...wow how cool would that be.

us aussies use mmols...come to the dark side my american friends!

Nooooo!!! Never!!!!!

But seriously, such a change would confuse me to no end. What about folks who have been using mg/dL for the last 30 or 40 years (i.e., since home BG monitoring was available)? Even in a foggy, hypo state, I know that a number like 50 needs to be treated. If I was in some hypo fog and saw a 3.3, I would be so confused. Now what would help is if my meter displayed BOTH numbers so that I could learn to associate mM numbers with mg/dL numbers.

I agree that we would adjust. I have lived in countries on the metric system and I stopped "translating" after awhile, but I don't want to change either. In the case of "switching" to the metric system I found it to be much simpler and cleaner - units of 100 and 1000 rather than arbitrary 12's and 16's. But I think the opposite is true here - whole numbers are "cleaner" than decimal numbers.

But the bottom line, even if you want the change - don't hold your breath. I'm old enough to remember the various attempts of the U.s. to switch to the metric system - they went nowhere - fast. We're a country of pioneers, remember "I do it my way!

I like the bigger numbers better, Holger made some good points earlier in the thread. While the metric system the rest to the world uses is clearly superior, in this case I think ours has the advantage.

I adopted the term "metric" for the mmol/L system but actually mg/dL is also metric: Milligram (metric) per Deciliter (metric = 1/10 of a Liter). The fundamental difference is just how the concentration is expressed:

mg/dL: expresses the Milligrams per Deciliter
mmol/L: expresses the mols per Liter. 1 mol is equivalent to the number of atoms found in 12g of the carbon isotope 12C. BTW: why 12g and not 10g (head scratch)?

So one unit expresses weight the other the amount of atoms. In scientific terms the mmol/L is independent from the actual weight of the atoms. It expresses pure concentration in a fluid and thus it is favoured by scientists. In a weightless environment like the IIS you can only measure mmol/L.

Still I think this type of descriptive exactness is not important for us. It is important that things are measured metrically and both are measured this way. It is not the same as miles VS kilometers or feet VS meters.

You beat me to it... i was scratching my head here thinking, don't these people realize they are both metric units of measurement??

Actually I was referring to the metric system of measuring things like centimeters vs inches being superior, but did not state it very well. Although I do realize the numbers are equivalent, measuring in atoms does strike me as pretty cool :)

Interesting discussion! The other component of Aeon's "all new learning involves a little discomfort" argument is that it would also entail quite a bit of $$$, reprinting leaflets to read "your goal should be 7.8..." instead of "140", training doctors- "we know everything...we don't need training...", training nurses, dietitians, family members "OMG, your BG is 4.2!" *dials 911...*, etc. In an economic crisis of which health concerns are a big part, I don't see an innovation like this getting a lot of traction.

I fail to see why either system is better or worse and see no reason to change just for the sake of change. I'm like Zoe in that I remember the attempts to go all metric in this country. The attempts all failed, life goes on and no one is any worse off because they failed.

As long as I can get a meter that will read in mg/dl then I will continue to use that system. If my doctor, heatlh dept or anyone else wishes to switch then that's just fine and I will be glad to let them do the math.

I live in the southern US and there is sometimes seen an amusing bumper sticker on cars that reads simply "WE DO NOT REALLY CARE HOW YOU DID THINGS UP NORTH" I hope I have not Pissed off any of my northern friends. It is after all just a joke to me and a statement of southern pride.

I see no reason to change just to be like someone else if the change will not bring improvement.

Gary S

I think the rest of the world needs to switch to teaspoon per gallon.

I understand that to a mathematically trained person such as yourself that this makes perfect sense. But in everyday life both units of measure are abstract since the average person does not use either deciliters or moles in their daily life. As the saying goes "I would not know a deciliter if it walked up and bit me". Same could be said of a mole.

Again I fail to see the difference.

Gary S

I don't think the problem is the measurement, it's the target. 4-7 is a bit too broad to "aim" at. I would prefer resources be poured into marketing more aggressive targets and positive attitudes towards achieving them than in spending resources changing a scale. I still prefer 3 digit #s to 2 digit numbers. Except those two digit numbers < 100...

I like the clock thing, it is a unit I could get use to. A repeating 12 hour clock makes no sense in a 24 hour day. Your ten hour clock is just a different division of a known quanity, a day. Good luck with that one too. :-)

Gary S

And don't forget the Celcius /Fahrenheit calculation ...more to ponder over ?? I may admit having lived in the Netherlands till age 23 , it all seems in my mind easier " to get " :)