Good Morning, Mr. Fonorow...
I have a question about Ascorsine and diabetes.
Dad has his diabetes pretty well under control, but he has been getting some abnormal readings of late. He was reading (not sure where.. it was in a newspaper, but he cannot remember the source) that excessive levels of Vit C can cause erroneous readings in the regular blood glucose testers.
Do you have any information about this? Are you aware if it is a known problem? It would go a long way towards explaining some of his readings.
Apparently it might... I've been doing some looking, and on the FDA site..
it states (only the relevant part pasted here):
Factors That Affect Glucose Meter Performance The accuracy of your test results depends partly on the quality of your meter and test strips and your training. Other factors can also make a difference in the accuracy of your results.
Other Substances. Many other substances may interfere with your testing process. These include uric acid (a natural substance in the body that can be more concentrated in some people with diabetes), glutathione (an "anti-oxidant" also called "GSH"), and ascorbic acid (vitamin C). You should check the package insert for each meter to find what substances might affect its testing accuracy, and discuss your concerns with your health care provider.
Unfortunately, they don't suggest what to do. From reading about the errors with the urine test, it seemed that Vit C caused false positives (glucose appeared to be present when it was not). The excerpt above from the FDA site notes that Vit C can cause errors with the blood meters, and I am assuming that it will similarly cause a reading higher than the actual reading (which is what seems to be the case with Dad).
They speak about checking each meter's package insert for info as to if Vit C will affect it... so perhaps Dad might need to change his meter. I don't know if there are any meters that do not have a Vit C sensitivity, however.
From http://www.nlm.nih.gov/medlineplus/ency ... 003438.htm
Range from before-meal glucose levels of 90 to 130 milligrams per deciliter (mg/dL); after-meal values of less than 180 mg/dL. Values can vary depending on physical activity, meals, and insulin administration. Normal value ranges may vary slightly among different laboratories.
Vitamin C blood levels range up to 1.5 mg/dl - so even if vitamin C were being counted by the blood analysis, the vitamin would only add a maximum of 1 to 2 percent to the reading.
Urine is a different animal because "replacement " (not excessive!) doses of vitamin C wind up in the urine, but since a) animals make these amounts all day long, and b) most blood tests are probably tested on laboratory animals, one would think the urine tests would be able to account or filter ascorbate by now.