Fasting Blood Glucose Questions

On 13 Feb 2004 09:39:36 -0800, [email hidden] (King David)

Quoted message said:

I'd like to better understand how Fasting Blood Glucose "FBG" works or means. For a non-diabetic
person who fasts for 12 hours I gather the FBG is the quiescent glucose in the plasma and will stay
at that level until the fast goes on for too long at which point other things will start to happen.
Is that pretty much it? I assume if diet is motified the FBG will likely not substantially change.

For an insulin impaired person, what are the dynamics? Do they also reach a quiscent state with
a higher FBG or does it take them more time than 10-12 fasting hours? I suspect that they may
have a higher BG reading immediately after a meal, but how long does it take to reach a quisent
state. If diet is changed I assume it can affect the post-meal BG, but, will it show on the FBG
and if so why?

Finally, what are the dynamics for a T-1 person?

are you type 1 or type 2?

your weight? your average carbs per meal? your meds?

Mack Type 1 since 1975 alt-support-diabetes.orgalt-support-diabetes.orgOpen ↗ insulin-pumpers.orginsulin-pumpers.orgOpen ↗

In tribute to the United States of America and the State of Israel, two bastions of strength in a
world filled with strife and terrorism.

BG levels are not constant, even during fasting. (Hormone levels fluctuate and trigger the release
of stored glycogen before waking, for example.) In fact this is often why a fasting bg test is used
for diagnosis - it's more consistent. Insulin resistance (for type 2) is often more pronounced early
in the morning and those with insufficient insulin levels can't regulate the overshoot either.

Meal choices sometimes can change the fbg result - but this tends to be more common if someone has
been going low overnight and then getting the liver "dump" correction (more common for type 1). In
that case an evening snack with a slow and steady carb release (ie with fat and protein) will
eliminate the result. Waking up at different times over a week and testing in the middle of the
night can show how bg levels are changing for a clue on how to adjust things. Exercise timing and
activity level can shift morning bg results.

As to how long it takes to return to "normal" after a meal, it depends on the meal - % of calories
as carbs (versus fat and protein), and the "speed" of digestion for those carbs. (Fiber content is
important.) Again, exercise will shift this result too.

Insulin users have to consider the type of insulin (peaks, dispersal rate, etc.) as well as the carb
load. (Pumpers and MDI people have an easier time in some respects but still have to consider their
meal speed.) Cindy Wells (I hope this helps somewhat - your numbers will be different than mine.)

King David wrote in message <[email hidden]>...

Quoted message said:

I'd like to better understand how Fasting Blood Glucose "FBG" works or means. For a non-diabetic
person who fasts for 12 hours I gather the FBG is the quiescent glucose in the plasma and will stay
at that level until the fast goes on for too long at which point other things will start to happen.
Is that pretty much it? I assume if diet is motified the FBG will likely not substantially change.

For an insulin impaired person, what are the dynamics? Do they also reach a quiscent state with
a higher FBG or does it take them more time than 10-12 fasting hours? I suspect that they may
have a higher BG reading immediately after a meal, but how long does it take to reach a quisent
state. If diet is changed I assume it can affect the post-meal BG, but, will it show on the FBG
and if so why?

Finally, what are the dynamics for a T-1 person?

FbG will measure an equilibrium which your body reaches during the night.

That equilibrium is a moving balance between your particular:

a. Level of insulin resistance
b. Degree of damage to beta cells
c. Morning Hormones Release Rates
d. Level of carb in your belly and glucose in your blood when you go to bed

Folks with diabetes have elevated FbG because they have damaged beta cells and can't make
enough insulin.

Folks with Type 2 diabetes usually have high Insulin Resistance so the effects of the damage to
their beta cells is amplified. However, in early days, Type 1 diabetics have more damage. Thus, the
need for medication in both types can be monitored by following their FbG.

Hormone levels are a genetic [censored] shoot.

The general pattern of bG during the night is a tendency to fall until about 3 am, and a strong
tendency to rise between 3 am and sometime in the morning. My morning effect is still going strong
at 10 am. Thus, your FbG also depends on the time of day you choose to measure it.

All in all, FbG is a marker, useful for detecting damage due to diabetes. However, the bG needed for
a formal definition of Diabetes is an arbitrary and somewhat capricious level set by committees
composed of folks with differing agendas.

Some FbG/Diabetes Diagnosis Reductio ad absurdum examples:

1. Best I can tell, some of the Insurance Companies would prefer a 200 mg/dL level. Anybody
with a lower FbG must pay for their own meds since they "don't have diabetes"

2. My personal opinion: Since 85 mg/dL is "normal", anybody with an 86 or higher should start
immediate insulin.

Regards
Old Al

[email hidden] (King David) wrote in
:"]news:[email hidden]:

Quoted message said:

I'd like to better understand how Fasting Blood Glucose "FBG" works or means. For a non-diabetic
person who fasts for 12 hours I gather the FBG is the quiescent glucose in the plasma and will
stay at that level until the fast goes on for too long at which point other things will start to
happen. Is that pretty much it? I assume if diet is motified the FBG will likely not
substantially change.

For an insulin impaired person, what are the dynamics? Do they also reach a quiscent state with
a higher FBG or does it take them more time than 10-12 fasting hours? I suspect that they may
have a higher BG reading immediately after a meal, but how long does it take to reach a quisent
state. If diet is changed I assume it can affect the post-meal BG, but, will it show on the FBG
and if so why?

Finally, what are the dynamics for a T-1 person?

Non-diabetic: Although there are differences in fasting response in men and women, the first order
model for bg vs. time up to 24 hours is a linear decline in bg. The lower normal bound for males at
24 hours is 55 mg/dl. For females it is 38 mg/dl. Things get more complex beyond 24 hours, but in
all cases bg continues to declines. There is no flattening out to a stable fasting glucose level, at
least as far out as 72 hours.

Type 2: Remember that type 2 diabetes is a family of diseases with common clinical features, not
a single monolithic disease. This leads, as you might expect, to a variety of responses depending
on the details of the particular patient's problem influenced by the particular medications
taken, if any.

Type 1: Again, type 1 is a family of diseases, but since the hallmark is an absolute deficiency of
insulin, the dynamics of bg cannot be separated from the interaction of the dynamics of insulin
input and the dynamics of food input. The variability of insulin input regimens is huge, from a
single shot of medium or long acting insulin per day to a pumper with multiple basal inputs at
different times of day and variable insulin:carbohydrate ratios depending on time of day and
activity level. The simple model for the 1 shot/day regimen is a continuously falling bg level,
punctuated by meal induced increases in bg level.

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

Quoted message said:

Non-diabetic: Although there are differences in fasting response in men and women, the first order
model for bg vs. time up to 24 hours is a linear decline in bg. The lower normal bound for males
at 24 hours is 55 mg/dl. For females it is 38 mg/dl. Things get more complex beyond 24 hours, but
in all cases bg continues to declines. There is no flattening out to a stable fasting glucose
level, at least as far out as 72 hours.

So you're saying that the liver will not act and deliver more glucose to the body ? You say that it
keeps going lower ??