H1A levels

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

The latests, most scientific discussion I have found is at:

care.diabetesjournals.org275Open ↗

The mathematical equation is:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

That assumes that your Clinical Lab uses an HbA1c
calibration which corresponds to the U.S. DCCT calibration.

Regards
Old Al

Thank You

"oldal4865" <[email hidden]> wrote in news:2hgpcnFcebs0U1@uni-
berlin.de:

Quoted message said:

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

The latests, most scientific discussion I have
found is at:

care.diabetesjournals.org2Open ↗
5/2/275

The mathematical equation is:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

That assumes that your Clinical Lab uses an HbA1c
calibration which corresponds to the U.S. DCCT
calibration.

Regards
Old Al

oldal4865 <[email hidden]> wrote on Tue, 25 May 2004 07:36:13 -0400:

Quoted message said:

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have
found is at:

Quoted message said:

care.diabetesjournals.org2Open ↗
5/2/275

Quoted message said:

The mathematical equation is:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

Wow! Didn't know that. Mind if I calculate a little table?

Ave bG HbA1c 80 4.4 120 5.5 160 6.7 200 7.8 250 9.1 300 10.6
400 13.4 (is this patient still alive?)

Quoted message said:

That assumes that your Clinical Lab uses an HbA1c
calibration which corresponds to the U.S. DCCT
calibration.

Quoted message said:

Old Al

--
Alan Mackenzie (Munich, Germany) Email: [email hidden]; to
decode, wherever there is a repeated letter (like "aa"😉,
remove half of them (leaving, say, "a"😉.

Alan Mackenzie <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

oldal4865 <[email hidden]> wrote on Tue, 25 May 2004
07:36:13 -

0400:

Quoted message said:

Quoted message said:

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A

level

Quoted message said:

Quoted message said:

Quoted message said:

correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have found
is at:

Quoted message said:

care.diabetesjournals.org25Open ↗
/2/275

Quoted message said:

The mathematical equation is:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

Wow! Didn't know that. Mind if I calculate a little table?

Ave bG HbA1c 80 4.4 120 5.5 160 6.7 200 7.8 250 9.1 300
10.6 400 13.4 (is this patient still alive?)

Quoted message said:

That assumes that your Clinical Lab uses an HbA1c
calibration which corresponds to the U.S. DCCT
calibration.

Quoted message said:

Old Al

Yes they may very well be alive. I ahve seen Bg as high as
700 wiht patient acting normal.

In article <[email hidden]>,

Pimamedic said:

Alan Mackenzie <[email hidden]> wrote in
:"]news:[email hidden]:

Quoted message said:

oldal4865 <[email hidden]> wrote on Tue, 25 May
2004 07:36:13 -

0400:

Quoted message said:

Quoted message said:

Pimamedic wrote in message ...
>I am a type II diabetic I am wantiong to understand hwo
>does a H1A

level

Quoted message said:

Quoted message said:

>correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have found
is at:

Quoted message said:

care.diabetesjournals.orgcare.diabetesjournals.orgOpen ↗
2/275

Quoted message said:

The mathematical equation is:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

Wow! Didn't know that. Mind if I calculate a little
table?

Ave bG HbA1c 80 4.4 120 5.5 160 6.7 200 7.8 250 9.1 300
10.6 400 13.4 (is this patient still alive?)

Quoted message said:

That assumes that your Clinical Lab uses an HbA1c
calibration which corresponds to the U.S. DCCT
calibration.

Quoted message said:

Old Al

Yes they may very well be alive. I ahve seen Bg as high as
700 wiht patient acting normal.

I had an HbA1c of 15 at diagnosis. I was tired and thirsty a
lot, but the complaint that had brought me to the doctor was
joint pain that turned out to be totally unrelated to the
diabetes (and uncorrelated with bG levels).

--
AF

Pimamedic said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

It DOESN'T !! Two different measures, no matter what the
others here say there is NO DIRECT correlation between
average BG as average BG is a MYTH and nealry IMPOSSIBLE to
measure accurately !!

(gman99) said:

Pimamedic said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

Quoted message said:

It DOESN'T !! Two different measures, no matter what the
others here say there is NO DIRECT correlation between
average BG as average BG is a MYTH and nealry IMPOSSIBLE to
measure accurately !!

If it's nearly impossible to measure accurately it can't be
a myth. And it's actually quite easy to measure accurately
in a by using a permanently attached blood glucose monitor
supplying its readings to a data collection computer. Not
much more complicated than a Holter heart monitor.

--
Chris Malcolm [email hidden] +44 (0)131 651 3445 DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
["]http://www.dai.ed.ac.uk/homes/cam/]

oldal4865 <[email hidden]> wrote on Tue, 25 May 2004 07:36:13 -0400:

Quoted message said:

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have
found is at:

Quoted message said:

care.diabetesjournals.org2Open ↗
5/2/275

Quoted message said:

The mathematical equation is:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

I have constructed two spreadsheets, one looking like what
my average daily blood glucose levels would have been when I
innocently scoffed down shepherd's pie, pasta, big bowls of
muesli for breakfast, slugged down half a pint of fresh
orange juice etc.. That one frequently exceeded 11 mmol/l
(200 US). The other is based on my new careful avoid-the-high-
spikes diet. That one rarely exceeds 7.5 (135). I then
averaged the readings throughout each of the two types of
day and converted to HbA1c using the above formula. The
difference is approx .5 -- not much!

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG behaviour)
is making changes in the fasting BG level.

What is interesting about this is the papers which have
shown a linear reduction of risk of various diabetic
disorders with decreasing HbA1c. If HbA1c actually gives
the result of average BG over time -- which it would do if
the glycation of the hemoglobin followed the usual mass
action law of chemical reaction in aqueous solutions --
then I can deduce that getting *fasting* BG down, and
keeping it there for long periods, will make (for me) the
most dramatic reductions in risk, i.e., reduce progressive
diabetic damage the most.

I don't know how the blood glucose of all you folk behaves,
but the behaviour I've observed in mine tends to drop after
a meal in a few hours to about 5.5 (100), and then takes a
few more hours drifting slowly down to to 4.5 (80). Getting
down to bottom fasting level takes a long time. As a
consequence I get the lowest BG averages by having a few
meals with long enough intervals between them to get down
low and stay low for a good period of time, rather than, as
is often recommended here, having frequent smaller meals
with smaller spikes.

In sum, at least with my typical BG behaviour, it looks like
the thing to aim for is excavating the valleys of the BG
graph deeper, rather than trying to minimise the spikes. And
that is achieved by leaving longer gaps between meals, i.e.,
fewer bigger meals rather than more smaller meals.

It's obvious once I think about it: the thing about spikes
is they're spiky, i.e., steep side and pointy. Whereas the
valleys between are much more rounded. If you turned a
valley upside down it would have much more stuff in it than
in a spike, a rounded hill rather than a sharp peak. Hence
the larger effect of valleys rather than peaks on the
average. Hence (for me) fewer bigger meals looks like the
best way to get low HbA1c levels.

--
Chris Malcolm [email hidden] +44 (0)131 651 3445 DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
["]http://www.dai.ed.ac.uk/homes/cam/]

Quoted message said:

If it's nearly impossible to measure accurately it can't
be a myth. And it's actually quite easy to measure
accurately in a by using a permanently attached blood
glucose monitor supplying its readings to a data
collection computer. Not much more complicated than a
Holter heart monitor.

And your measuring device has WHAT margin of error ??
5..10...15% ?? Is the error consistant ???

As I said, the supposed DIRECT correlation between
average BG and HbA1C is a myth. There is a relationship
between the two but it is NOT direct as the provided
formula would suggest.

Chris Malcolm said:

(gman99) said:

Pimamedic said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

Quoted message said:

It DOESN'T !! Two different measures, no matter what the
others here say there is NO DIRECT correlation between
average BG as average BG is a MYTH and nealry IMPOSSIBLE
to measure accurately !!

If it's nearly impossible to measure accurately it can't
be a myth. And it's actually quite easy to measure
accurately in a by using a permanently attached blood
glucose monitor supplying its readings to a data
collection computer. Not much more complicated than a
Holter heart monitor.

Average BG and degree of glycation (hb1ac) are *not* the
same thing, because all average bg is IS average BG.
Glycation is glycation. Propensity to glycation is not
standard, and may vary within the individual over time. Your
bg may average 7 and yet your hb1ac is 6 whereas my average
might be also be 7 but my hb1ac is 5 because I am more
resistant to glycation. This is why it is folly to say that
a hb1ac corresponds to an average - it doesn't. It
corresponds to control, and the closer you are to 5% the
less statistically likely you will have diab. complications.

Remember that even non-diabetics can have diabetic
complications for the same kind of reasons (they glycosolate
to a detrimental extent even with bg #s in the normal range)

--
John38 - T2

On Thu, 10 Jun 2004 13:14:29 +0000 (UTC), [email hidden] (Chris

Malcolm) said:

oldal4865 <[email hidden]> wrote on Tue, 25 May 2004
07:36:13 -0400:

Quoted message said:

Pimamedic wrote in message ...

Quoted message said:

I am a type II diabetic I am wantiong to understand hwo
does a H1A level correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have found
is at:

Quoted message said:

care.diabetesjournals.org25Open ↗
/2/275

Quoted message said:

The mathematical equation is:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

I have constructed two spreadsheets, one looking like what
my average daily blood glucose levels would have been when
I innocently scoffed down shepherd's pie, pasta, big bowls
of muesli for breakfast, slugged down half a pint of fresh
orange juice etc.. That one frequently exceeded 11 mmol/l
(200 US). The other is based on my new careful avoid-the-high-
spikes diet. That one rarely exceeds 7.5 (135). I then
averaged the readings throughout each of the two types of
day and converted to HbA1c using the above formula. The
difference is approx .5 -- not much!

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG behaviour)
is making changes in the fasting BG level.

What is interesting about this is the papers which have
shown a linear reduction of risk of various diabetic
disorders with decreasing HbA1c. If HbA1c actually gives
the result of average BG over time -- which it would do if
the glycation of the hemoglobin followed the usual mass
action law of chemical reaction in aqueous solutions --
then I can deduce that getting *fasting* BG down, and
keeping it there for long periods, will make (for me) the
most dramatic reductions in risk, i.e., reduce progressive
diabetic damage the most.

I don't know how the blood glucose of all you folk behaves,
but the behaviour I've observed in mine tends to drop after
a meal in a few hours to about 5.5 (100), and then takes a
few more hours drifting slowly down to to 4.5 (80). Getting
down to bottom fasting level takes a long time. As a
consequence I get the lowest BG averages by having a few
meals with long enough intervals between them to get down
low and stay low for a good period of time, rather than, as
is often recommended here, having frequent smaller meals
with smaller spikes.

In sum, at least with my typical BG behaviour, it looks
like the thing to aim for is excavating the valleys of the
BG graph deeper, rather than trying to minimise the spikes.
And that is achieved by leaving longer gaps between meals,
i.e., fewer bigger meals rather than more smaller meals.

It's obvious once I think about it: the thing about spikes
is they're spiky, i.e., steep side and pointy. Whereas the
valleys between are much more rounded. If you turned a
valley upside down it would have much more stuff in it than
in a spike, a rounded hill rather than a sharp peak. Hence
the larger effect of valleys rather than peaks on the
average. Hence (for me) fewer bigger meals looks like the
best way to get low HbA1c levels.

Hi Chris

My philosophy is diametrically opposed. I will still do my
best to get the spikes down, and I've found that my FBG and
A1c have eventually followed. I also eat less more often,
small meals through the day. I must admit I've never worried
much about the averages, because they are so dependant on
the timing of the tests.

From my reading the spikes are also causing damage, not just
the A1c levels.

You will find discussion of this point, and a different
logic on the relationship between post-prandial excursions
and HbA1c at medscape.com3036 indexOpen ↗
, although there are some other references. There doesn't
appear to have been a lot of research specifically on post-
prandial/HbA1c relationships.

For example, Slide 12:

"Is it fasting or postprandial hyperglycemia that is
important? Hemoglobin A1C measures total exposure to
hyperglycemia over about a 3-month period of time. Both
fasting and postprandial hyperglycemia contribute to this.
We have no evidence that there's anything more toxic for
postprandial hyperglycemia vs fasting hyperglycemia. The
relative contributions depend on the relative degree of
glycemic control. When your HbA1C is very high, when you
have a fasting glucose level over 200
mg/dL, most of the HbA1C will be due to fasting
hyperglycemia. However, earlier in the stage of diabetes,
when HbA1C levels are lower, it's going to be the
postprandial values that contribute most to HbA1C."

Cheers, Alan, T2 d&e, Australia. Remove weight and
carbs to email.
--
Everything in Moderation - Except Laughter.

[email hidden] (Chris Malcolm) wrote in
:"]news:[email hidden]:

Quoted message said:

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG
behaviour) is making changes in the fasting BG level.

If you look at the FAQ section on A1c, there are a
references to a series of papers by Henrik Mortensen
describing the reaction, the forward and reverse reaction
constants, and a numerical solution to a two box model of
the reaction. The numerical model at least is relatively
insensitive to short term spikes.

--
-------
Charly Coughran [email hidden]

[email hidden] (gman99) wrote in misc.health.diabetes:

Quoted message said:

And your measuring device has WHAT margin of error ??
5..10...15% ?? Is the error consistant ???

This is a general measuring problem and has nothing to do
with a supposed correlation.

Quoted message said:

As I said, the supposed DIRECT correlation between average
BG and HbA1C is a myth. There is a relationship between
the two but it is NOT direct as the provided formula would
suggest.

Both measurements refer to the abundance of BG in your blood
- one to short term, one to long term levels. It's very well
possible to have a direct yet rough indication of your
average BG values and your HbA1c, but there's indeed not
much use to measuring HbA1c if you can calculate it with
long term BG's.

My BG tells me something about the effectivity of my insulin
_now_, and my HbA1c tells me something about my general
regulation. I agree that there's not much use in using a few
snapshots to tell the overall story of a movie.

--
CeeBee

EMH Mark I: "Stop breathing down my neck." EMH Mark II: "My
breath is merely a simulation." EMH Mark I: "So is my neck.
Stop it anyway."

Quoted message said:

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG
behaviour) is making changes in the fasting BG level.

that's because there is NO causal link between the two.
Glycation (measured by the HbA1c) is a chemical reaction
which takes a while. It is therefore logical to assume that
the spike needs not only height, but duration in order to
affect the HbA1c...therefore, a spike of 10.0 reduced to 6.0
within a short period of time will produce fewer glycated
cells than say a moderate spike of 8.0 that lasts longer....

On Thu, 10 Jun 2004 13:14:29 +0000 (UTC), [email hidden] (Chris

Malcolm) said:

I have constructed two spreadsheets, one looking like what
my average daily blood glucose levels would have been when
I innocently scoffed down shepherd's pie, pasta, big bowls
of muesli for breakfast, slugged down half a pint of fresh
orange juice etc.. That one frequently exceeded 11 mmol/l
(200 US). The other is based on my new careful avoid-the-high-
spikes diet. That one rarely exceeds 7.5 (135). I then
averaged the readings throughout each of the two types of
day and converted to HbA1c using the above formula. The
difference is approx .5 -- not much!

Chris,

I ran into this when I was setting up my own spreadsheet.
For the calculations to be accurate you need to have a meter
continually monitoring your BG level and spitting out the
readings to your spreadsheet values say every 5 minutes of
the day. Unless you have this you are going to be subject to
the vagaries of when you take a measurement and whether that
is on a peak or a trough or somewhere in between.

Say, for example, you have readings of 7.5 and 4.5. The
average of these figures is 6 but you have no way of knowing
if these readings are actual maximum and minimum readings
and how the BG varies between those readings. Depending on
whether the BG peaks are narrow or broad your real average
could be anywhere between say 5 and 7.

Your calculations will be a useful guide but may be in error
by +/- 0.5 or more so don't take them too seriously.

Cheers, John

Use au instead of invalid for emails to me.

---

"Chris Malcolm" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

[ ... ]

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG
behaviour) is making changes in the fasting BG level.

[ ... ]

That is my practical experiance as well, and I have
found a logical explanation for it, based on my
observations of myself.

If my fasting BG is low, the whole day is likely to be great
and life is easy.

If my fasting BG is high, the whole day may be high or at
least jogging up and down. Sometimes I overcompensate for
the high BG. Sometimes I take far too little.

--
Have a nice day! Bjørn BL.

Chris Malcolm <[email hidden]> wrote on Thu, 10 Jun 2004 13:14:29
+0000 (UTC):

Quoted message said:

I have constructed two spreadsheets, one looking like what
my average daily blood glucose levels would have been when
I innocently scoffed down shepherd's pie, pasta, big bowls
of muesli for breakfast, slugged down half a pint of fresh
orange juice etc.. That one frequently exceeded 11 mmol/l
(200 US). The other is based on my new careful avoid-the-high-
spikes diet. That one rarely exceeds 7.5 (135). I then
averaged the readings throughout each of the two types of
day and converted to HbA1c using the above formula. The
difference is approx .5 -- not much!

Quoted message said:

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG
behaviour) is making changes in the fasting BG level.

Chris, who gives a damn about HbA1c? OK, that was a
hysterical rhetorical question, but an HbA1c isn't going to
do you any harm. HbA1c is an indicator, a _mere_ indicator
of how your BS has been on average. On the other hand, high
BS is might well damage you, even in short spikes, short
enough not to be "recorded" in HbA1c levels.

Quoted message said:

What is interesting about this is the papers which have
shown a linear reduction of risk of various diabetic
disorders with decreasing HbA1c. If HbA1c actually gives
the result of average BG over time -- which it would do if
the glycation of the hemoglobin followed the usual mass
action law of chemical reaction in aqueous solutions --
then I can deduce that getting *fasting* BG down, and
keeping it there for long periods, will make (for me) the
most dramatic reductions in risk, i.e., reduce progressive
diabetic damage the most.

HbA1c is _correlated_ with risk of disorders. If you
actively try to reduce your HbA1c, you may just be breaking
that correlation rather than reducing the risk. Think of
HbA1c as the temperature gauge of a nuclear reactor core. If
the gauge tells you the core's getting unexpectedly hot, you
investigate why - there could be serious damage in there.
What you don't do is slam in a few control rods to reduce
the temperature and then carry on as if everything's fine.
And you certainly DON'T "recalibrate" the gauge.

Quoted message said:

Chris Malcolm

--
Alan Mackenzie (Munich, Germany) Email: [email hidden]; to
decode, wherever there is a repeated letter (like "aa"😉,
remove half of them (leaving, say, "a"😉.

Alan said:

On Thu, 10 Jun 2004 13:14:29 +0000 (UTC),
[email hidden] (Chris Malcolm) wrote:

Quoted message said:

Quoted message said:

oldal4865 <[email hidden]> wrote on Tue, 25 May 2004
07:36:13 -0400:

Quoted message said:

Quoted message said:

Quoted message said:

Pimamedic wrote in message ...
>I am a type II diabetic I am wantiong to understand hwo
>does a H1A level correspond to a average bg reading.

Quoted message said:

The latests, most scientific discussion I have found is
at: care.diabetesjournals.orgcare.diabetesjournals.orgOpen ↗
25/2/275 The mathematical equation is:

Quoted message said:

Quoted message said:

Quoted message said:

Ave bG (mg/dL) = 35.6 x HbA1c - 77.3

Quoted message said:

Quoted message said:

I have constructed two spreadsheets, one looking like what
my average daily blood glucose levels would have been when
I innocently scoffed down shepherd's pie, pasta, big bowls
of muesli for breakfast, slugged down half a pint of fresh
orange juice etc.. That one frequently exceeded 11 mmol/l
(200 US). The other is based on my new careful avoid-the-high-
spikes diet. That one rarely exceeds 7.5 (135). I then
averaged the readings throughout each of the two types of
day and converted to HbA1c using the above formula. The
difference is approx .5 -- not much!

It surprised me is to find how little difference bringing
the spikes down a lot has on Hb1Ac. But it's a logical
consequence of the arithmetic. What *does* make a large
difference in HbA1c (in this simulation of my BG
behaviour) is making changes in the fasting BG level.

What is interesting about this is the papers which have
shown a linear reduction of risk of various diabetic
disorders with decreasing HbA1c. If HbA1c actually gives
the result of average BG over time -- which it would do if
the glycation of the hemoglobin followed the usual mass
action law of chemical reaction in aqueous solutions --
then I can deduce that getting *fasting* BG down, and
keeping it there for long periods, will make (for me) the
most dramatic reductions in risk, i.e., reduce progressive
diabetic damage the most.

I don't know how the blood glucose of all you folk
behaves, but the behaviour I've observed in mine tends to
drop after a meal in a few hours to about 5.5 (100), and
then takes a few more hours drifting slowly down to to 4.5
(80). Getting down to bottom fasting level takes a long
time. As a consequence I get the lowest BG averages by
having a few meals with long enough intervals between them
to get down low and stay low for a good period of time,
rather than, as is often recommended here, having frequent
smaller meals with smaller spikes.

In sum, at least with my typical BG behaviour, it looks
like the thing to aim for is excavating the valleys of the
BG graph deeper, rather than trying to minimise the
spikes. And that is achieved by leaving longer gaps
between meals, i.e., fewer bigger meals rather than more
smaller meals.

It's obvious once I think about it: the thing about spikes
is they're spiky, i.e., steep side and pointy. Whereas the
valleys between are much more rounded. If you turned a
valley upside down it would have much more stuff in it
than in a spike, a rounded hill rather than a sharp peak.
Hence the larger effect of valleys rather than peaks on
the average. Hence (for me) fewer bigger meals looks like
the best way to get low HbA1c levels.

Quoted message said:

Hi Chris

Quoted message said:

My philosophy is diametrically opposed. I will still do my
best to get the spikes down, and I've found that my FBG and
A1c have eventually followed.

Of course they will. Any decrement in BG level is a
decrement. The question at issue is which strategy gives the
most bang for the buck.

Quoted message said:

I also eat less more often, small meals through the day. I
must admit I've never worried much about the averages,
because they are so dependant on the timing of the tests.

That's not the right kind of average. To average BG through
the day you need to sum the area under the curve. For
example, doing it numerically, you could interpolate
readings every 10 mins, adjusting every reading to that
interval, and then average the lot.

Quoted message said:

From my reading the spikes are also causing damage, not
just the A1c levels.

The important question is whether the spikes cause *more*
damage than their simple averaging into the HbA1c. The way
that so many risk factors have be found to decrease linearly
with decreasing HbA1c suggests strongly that the spikes
cause damage simply proportional to their size and width. If
so, then averaging them completely captures the amount of
their damaging effect, with no extra special "spike factor"
left over.

Quoted message said:

You will find discussion of this point, and a different
logic on the relationship between post-prandial excursions
and HbA1c at medscape.com3036 indexOpen ↗
, although there are some other references.

Yes, I'm familiar with that.

*If* HbA1c is a simple derviation from the average BG, and
there are good general biochemical reasons for supposing
that by default, and *if* decreasing HbA1c numbers relate
linearly to decreased risk, which several papers have found
for different risks, we can then reasonably assume that
average BG should also simply correlate with risk values.

Quoted message said:

For example, Slide 12:

Quoted message said:

"Is it fasting or postprandial hyperglycemia that is
important? Hemoglobin A1C measures total exposure to
hyperglycemia over about a 3-month period of time. Both
fasting and postprandial hyperglycemia contribute to this.
We have no evidence that there's anything more toxic for
postprandial hyperglycemia vs fasting hyperglycemia. The
relative contributions depend on the relative degree of
glycemic control. When your HbA1C is very high, when you
have a fasting glucose level over 200
mg/dL, most of the HbA1C will be due to fasting
hyperglycemia. However, earlier in the stage of
diabetes, when HbA1C levels are lower, it's going to be
the postprandial values that contribute most to HbA1C."

I agree with everything except that last sentence, which
will only be true given a certain kind of shape to the meal-
response BG curve, a shape which my own personal BG response
curve very definitely does not have. The problem with that
last statement is that it is trying to express a complex
mathematical relationship without doing any maths. As it
happens, today we have to hand spreadsheets which are easily
capable of doing the requisite maths. Biochemical mass
action reactions, in which the speed of reaction depends on
the amount of the chemical present, follow simple Newtonian
dynamics, and the control of blood sugar by insulin, if you
still have at least a partly functioning control system,
follows the simple rules of a damped proportional control
system. There are lots of homeostatic mechanisms in the body
which behave like that. It's the simplest most basic control
mechanism.

It's that kind of control which gives the spikes their spiky
nature, compared to the wider scooped out valleys.

Of course if you're a type 1 using insulin in feedforward
estimate control (e.g. "I'm going to eat so much carb, so
I'll inject this much insulin to take care of it"😉, rather
than natural continuous feedback control, then the spikes
will be of a different shape and my argument may not hold.
--
Chris Malcolm [email hidden] +44 (0)131 651 3445 DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
["]http://www.dai.ed.ac.uk/homes/cam/]

Quoted message said:

Both measurements refer to the abundance of BG in your
blood - one to short term, one to long term levels. It's
very well possible to have a direct yet rough indication
of your average BG values and your HbA1c, but there's
indeed not much use to measuring HbA1c if you can
calculate it with long term BG's.

Ah...no, HbA1c measures glycated Haemeglobin, NOT blood
glucose, they are two COMPLETELY different things !!

BG tells you how much glucose is swimming around in your
blood at a given point in time. HbA1c measures glycated
haemeglobin. Heamoglobin becomes glycated when one's BG is
at a certain point for a certain amount of time, glycation
is a fairly long reaction. HbA1c indicates overall control
of one's BG but cannot betranslated into spikes or any other
BG measurement.