I believe I have hypoglycemia. After eating a lot of fruit and sugar
and alchohol I frequently test my blood sugar level with those
personal machines. It reads then about 140. Normally it is 90. I have
been told that the normal level is between 70 and 110. Other doctors
have told me its between 60 and 120. My question is, what is the
'normal' blood sugar level reading and with a reading of 140 (after a
lot fo sugar) what problems might I expect and how dangerous is that
level?

Declan

Hi declan,

As you know, it would be best to have your blood sugar tested by a
physician who can review your entire medical history to interpret the
results. That said, if you'd like to test yourself before your
appointment, it would be best to follow some guidelines.

Diabetes Mellitus--Understanding Lab Tests: Screening Tests:
"Screening tests are generally fast, easy to perform, and cheap.
(Health fairs often offer free screening tests, for example.)
Screening tests require as little as a drop of blood from your
fingertip and take only a minute or two to complete.
Many doctors do not screen everyone for diabetes during regular
checkups. The chance of finding the disease in most people is just too
low. But screening tests are useful for people who may be at risk for
developing diabetes. If you or a family member suspect diabetes a
screening test should be done.
Who Is at Risk for Diabetes?
1. Individuals with a family history of diabetes, specifically mother,
father, brother, sister or grandparent or other close relatives.
2. Women with unexplained miscarriages or stillbirths or who have had
babies weighing 9 pounds or more at birth.
3. African Americans, Hispanics, Hawaiians and Native Americans.
4. People with a condition known as "impaired glucose tolerance" (see
Oral Glucose Tolerance Test below).
5. People with high blood pressure or very high blood cholesterol or
triglyceride levels.
6. People who are obese.
7. People over age 65.
It is recommended that these individuals should have a screening test
at least every three years. This is okay as long as the results are
entirely normal. If you have an abnormal screening test result, you
should have a diagnostic test performed.
Never compare your test results with other family or friends, this can
confuse or alarm you unnecessarily. You may not have had the same type
of test, therefor your results may not only have a completely
different meaning, they may not even be comparable.
http://www.well-net.com/diabetes/dmunderstandinglabtests-1.html

Rather than taking a sample after ingesting alot of sugar, it would be
more accurate to test your blood in the morning before you eat
anything (make sure your finger is completely dry).

Fingerstick blood glucose:  Fasting plasma glucose: 
"...You will be asked to eat or drink nothing for 8 hours before
having your blood drawn (usually first thing in the morning). If the
blood glucose level is greater than or equal to 126 mg/dL without
eating anything [on two or more tests on different days], you probably
have diabetes."
http://www.emedicinehealth.com/articles/17044-5.asp

"The fasting blood glucose (sugar) test is the preferred way to
diagnose diabetes. It is easy to perform and convenient. After the
person has fasted overnight (at least 8 hours), a single sample of
blood is drawn and sent to the laboratory for analysis.
Normal fasting plasma glucose levels are less than 110 milligrams per
deciliter (mg/dl). Fasting plasma glucose levels of more than 126
mg/dl on two or more tests on different days indicate diabetes. If the
overnight fasting blood glucose is greater than 126 mg/dl on two
different tests on different days, the diagnosis of diabetes mellitus
is made. A random blood glucose test can also be used to diagnose
diabetes. Random blood samples (if taken shortly after eating or
drinking) may be used to test for diabetes when symptoms are present.
A blood glucose level of 200 mg/dl or higher indicates diabetes, but
it must be reconfirmed on another day with a fasting plasma glucose or
an oral glucose tolerance test."
http://www.medicinenet.com/diabetes_mellitus/page3.htm

Additional Links of Interest:

How do you find out if you have diabetes?
"The Fasting Plasma Glucose Test is the preferred test for Type 1 and
Type 2 diabetes or pre-diabetes. You will fast overnight -- don't eat
anything for at least eight hours. The next morning your doctor will
draw blood from a vein and send your blood sample to a laboratory to
test how much glucose (sugar) is in your blood. It is best to have
this test done in the morning because afternoon results tend to be
lower.
* A normal glucose level is 110 milligrams per deciliter (mg/dl) or below.
* A pre-diabetes level is between 110 mg per dl and 125 mg per dl,
sometimes called impaired fasting glucose(IFG). This range is between
normal and having diabetes.
* A diabetic level is 126 mg/dl or higher."

"An Oral Glucose Tolerance Test (OGTT) may be done by your doctor to
test for Type 1 or Type 2 diabetes or gestational diabetes. After you
don't eat for 8-12 hours, your doctor will test the sugar in your
blood. Then you will drink a liquid rich in sugar (glucose) dissolved
in water. Over the next few hours, your doctor will test the sugar in
your blood again and check your numbers against standard numbers.
Here's what the test results can mean:
* A normal glucose level will be less than 140 mg/dl.
* A pre-diabetes level is between 141 mg/dl and 199 mg/dl, sometimes
called impaired glucose tolerance(IGT).
* A diabetic level is 200 mg/dl or more."
http://www.handsonhealth-sc.org/page.php?id=1141

The American Diabetes Association (ADA) recommends that you keep your
blood sugar levels within:
* 90 mg/dL to 130 mg/dL before meals and 110 mg/dL to 150 mg/dL at
bedtime when using a blood sample drawn from a fingertip (plasma blood
sample).
http://my.webmd.com/hw/health_guide_atoz/aa135726.asp

If you don't take insulin, test your blood sugar:
* When you wake up
* One to two hours after meals
http://yourmedicalsource.com/library/diabpreg/DPG_bloodsugar.html

How to Get a Good Blood Sample for Home Blood Glucose Monitoring:
Self Blood Glucose Monitoring Tips:
http://diabetes.about.com/cs/glucosemonitoring/qt/blqt_blood_drop.htm

About Diabetes Meter Master Quiz:
Twenty questions to measure your glucose monitoring knowledge:
http://diabetes.about.com/cs/glucosemonitoring/l/blsmbgquiz.htm

I hope this helps and you find your blood sugar to be well within
normal range. If you have any questions, please post a clarification
request *before* closing/rating my answer and I'll be happy to reply.

Thank you,
hummer

Google Search Terms Used:

normal blood sugar range 140
testing blood sugar level home kit
screening test blood sugar

Maybe, like me, you simply have low Glucose tolerance.

I discovered this years ago.

The presumption was that I might have had diabetes which would have
been worrying but over the years I've always been advised 'Nothing to
worry about'.

Hope your high sugar reading is also 'Nothing to worry about'.

Have you been for a Glucose Tolerance Test?

If not, I suggest you take one, to put your mind at rest.

Good luck!

The normals you quote, whether 70-110 or 60-120 are fasting levels -
i.e. nothing with calories for 8-12 hrs prior to test.  There are also
standards for the glucose tolerance test, which is done with an 8-12
hr fast, followed by a measured amount of glucose, with the test being
done at a set time after that glucose load.  With this test, a level
of 140 is the lower limit for impaired glucose tolerance, which can be
a warning sign that you are headed toward diabetes and will need
follow up.
However, your situation, which presumable does not involve fasting
first, and could involve larger or lesser amounts of sugars, which
probably include others than glucose, and also involves alcohol, which
can affect the test, is impossible to interpret - there are no
standards.  If the level was over 200, I would definitely be worried. 
Otherwise, would be reasonable to do either an 8-12 hour fasting level
(which if 110-125 may indicate impaired tolerance, or >125 might mean
diabetes) or a glucose tolerance test at your doctor's.

Either way, what you are talking about is hyperglycemia, not
hypoglycemia, which is low blood glucose, and is a more controversial
topic.