New Findings About Blood Sugar Tests
The blood test used by most doctors to clearly determine whether a patient is diabetic or pre-diabetic, the hemoglobin A1C test, measures how the body is managing sugar. However, Chris Kresser, an acupuncturist, functional medicine practitioner and author of the book, 9 Steps to Perfect Health, in Berkeley, California, has cast some doubt on its reliability in that regard.
The sugar circulating in our bloodstream is glucose. It binds to the red blood cells, where hemoglobin stores both iron and glucose for distribution to cells. The lab test most of us are familiar with checks our fasting blood sugar level in the morning, when we haven’t eaten for many hours. Another common test is the finger prick self-test with a glucose meter that thousands of diabetics and other people use daily to keep track of their blood sugar levels.
The hemoglobin A1C test is used to give a picture of how the body deals with sugar over a period of three months via a measure of glycated hemoglobin, or the glucose/hemoglobin combination, because it was determined that the life expectancy of the typical red blood cell is 90 days. Kresser noticed that test results for some of his patients’ A1C tests did not seem accurate. Those that were following a low-carbohydrate Paleo diet had higher A1C readings than they should. After doing some research, he learned that red blood cells in non-diabetics can last as long as 146 days and those of a diabetic could live
as few as 81 days.
The older red blood cells have more time to accumulate sugar, so the test results would be higher than they should be in a non-diabetic individual. The opposite would be true for the diabetic; the results would not reflect use of glucose over a 90-day period because the cells wear out faster and will have less sugar clinging to the hemoglobin.
A rarely used fructosamine test is another gauge of blood sugar utilization that measures the amount of glucose bound to protein (glycated serum protein) in the blood as an average over a two-to-three-week period. This test is not affected by the varying lifespan of red blood cells, so it is particularly useful for people that are anemic, have sickle cell disease or are pregnant.
For these reasons, Kresser likes to have his patients get both the fasting, post-meal, fructosamine and A1C tests for a complete picture. The test he thinks is the most reliable is the one we can do ourself at home with a simple finger prick.
For more information, visit ChrisKresser.com.
Susan Bischak, CNC, CCT, is a nationally certified nutritional consultant and certified clinical thermography technician at Vista Natural Wellness Center, in Oakland, NJ. Contact her at 201-644-0840 or VistaNaturalWellness.com.
