In response to the query how to measure your glucose tolerance, here is something I put together for another website I frequent.
Also Susan, I do teach biochemistry to medical students, and in particular amino acid metabolism. What I stress is that while there may be standard recommendations for 'normal' folks, when you deal with people that have metabolic disorders, one needs to modify those. Just like you wouldn't recommend a high protein diet for someone with kidney damage, for someone with impaired glucose tolerance its just the ticket. Also, in the range I am talking about, 1 g protein/ lb of LBM, should not stress the kidneys of a person with normal kidney function.
MEASURING GLUCOSE TOLERANCE: Here is a blurb I wrote up before and modified slightly for you guys (some of which was copied from wiki) on how to measure your glucose tolerance. Notice the info. on the home test which is what many of you may want to start with unless you can convince your docs to run one in a lab for you:
This is how an OGTT (oral glucose tolerance test) works in a lab (from wiki):
The patient should have been fasting for the previous 8-14 hours (water is allowed).
Usually the OGTT is scheduled to begin in the morning (0700-0800) as glucose tolerance exhibits a diurnal rhythm with a significant decrease in the afternoon. A zero time (baseline) blood sample is drawn.
The patient is then given a glucose solution to drink. The standard dose since the late 1970s has been 1.75 grams of glucose per kilogram of body weight, to a maximum dose of 75 g. It should be drunk within 5 minutes. Prior to 1975 a dose of 100 g was often used.
Blood is drawn at intervals for measurement of glucose (blood sugar), and sometimes insulin levels. The intervals and number of samples vary according to the purpose of the test. For simple diabetes screening, the most important sample is the 2 hour sample and the 0 and 2 hour samples may be the only ones collected. In research settings, samples may be taken on many different time schedules.
To do an OGTT test at home, it is good to take additional time points, especially to check for reactive hypoglycemia. If you are not sure of your technique, you may even want to take duplicate measurements, especially at the 60 and 120 minute points, and remember to wash your hands before each measurement:
You can order a very good glucose monitor here for only $20 (uses small sample volumes and has excellent accuracy): http://shopcart.shopmash.com/manu/10...5/product.aspx
The test strips are expensive, but if you get your doctor to write a prescription they are cheaper. The meter will come with 10 to get you started. You can also order the strips from the same supplier.
This is the test. Don't eat after you evening meal. Next morning, measure you blood glucose per the instructions with the meter. Then drink 75g of pure glucose (you can use cycling gels, usually they have 25 g of carbs in the form of maltodextrin which is essentially glucose so you would take 3, or how ever many add up to 75g of the brand of your choice, you can rinse them down with water). DO NOT EAT AGAIN UNTIL AFTER THE TEST IS OVER ALTHOUGH YOU CAN DRINK PLAIN WATER. Call t=0 when you first started eating the glucose. Measure the values at the following points: 30 min., 60 min, 120 min, and hourly thereafter until it comes to a value less than 100 (6-8 hours). The 1 hour reading should be less than 200, and the 2 hour reading should be less than 140 if you are 'normal'.
While I have given this test to lots of people, I have seen there is a huge range in the responses. Some folks never go above 120 at the 1 hour point, while others can be anywhere between 120 and 200. While these folks don’t meet the medical definition of impaired glucose tolerance, they definitely have less glucose tolerance than folks that never go over 120, and they often tend to take too long for the glucose load to clear. These folks often benefit greatly from a low carb diet. When you are feeling bad on the bike (if this happens to you after a high carb pre-ride meal), take a measurement as well. Also record how you are feeling.
So, what I (and my doctor) think is even more important for optimum health (not exposing your body to high blood sugar levels which harms your organs) is finding out how you react to diff. foods/combinations of foods, and only eat foods that keep your blood sugar under 120 after 1 hour (after the first bite) and under 100 after 2 hours (after the first bite). Exercise can be used to raise glucose tolerance. So, while you may find that your blood sugar goes high if you eat fruit pre-ride it may be fine post-ride.
Interpretation of OGTT results (from: http://en.wikipedia.org/wiki/Glucose_tolerance_test )
Fasting plasma glucose should be below 6.1 mmol/l (110 mg/dl). Fasting levels between 6.1 and 7.0 mmol/l (110 and 126 mg/dl) are borderline ("impaired fasting glycaemia"), and fasting levels repeatedly at or above 7.0 mmol/l (126 mg/dl) are diagnostic of diabetes.
The 2 hour glucose level should be below 7.8 mmol/l (140 mg/dl). Levels between this and 11.1 mmol/l (200 mg/dl) indicate "impaired glucose tolerance." Glucose levels above 11.1 mmol/l (200 mg/dl) at 2 hours confirms a diagnosis of diabetes.
Here is a More detailed way to look at your values From the National Library of Medicine http://www.nlm.nih.gov/medlineplus/e...rmal%20Values:
Normal blood values for a 75-gram oral glucose tolerance test used to check for type 2 diabetes:
Fasting: 60 to 100 mg/dL
1 hour: less than 200 mg/dL
2 hours: less than 140 mg/dL. Between 140-200 mg/dL is considered impaired glucose tolerance or pre-diabetes. This group is at increased risk for developing diabetes. Greater than 200 mg/dL is diagnostic of diabetes mellitus
What next?
If you have impaired glucose tolerance, follow the diet in this book, Dr. Bernstein's Diabetes Solution. You can also order it from amazon, etc. http://www.diabetes-normalsugars.com/ (although I do eat tomatoes, carrots, etc. which he doesn't recommend, depends on how severe your impaired glucose tolerance is). I also supplement with no carb protein shakes and almonds during exercise (Jay Robb Whey Protein which they sell at HEB Central Market, also contain electrolytes: http://www.jayrobb.com/cat_proteinWheyAll.asp), and am careful to eat plenty of protein to fuel activity. The amino acids are deaminated to carbon skeletons which can be burned for energy via the TCA cycle, and also used to do gluconeogenesis, but making glucose at a slower rate than consuming carbs on the bike. I have also trained myself to run on a high ratio of fat to glucose.
General info. on how to eat higher protein lower carb can be found in Protein Power by the Eades, although it is less based on glucose readings and allows fruits that raise my blood sugar too high. Another good book is good calories/bad calories by Gary Taubes. Even if you don't have impaired glucose tolerance, I believe it is a healthier way to eat although you would not be as restrictive as a person with impaired glucose tolerance. My husband doesn't have impaired glucose tolerance, but he eats the same as me although he sometimes supplements w carbs (like fruit, sometimes bread). But on the bike, he prefers a shake that contains carbs and protein to a pure carb one (cytomax, also has electrolytes which is key). I think its important to select a diet based on how it makes you feel. If you feel better by shifting the balance away from carbs and towards protein then you should do it regardless of what the test results show. I also think the carbs in veggies and fruits are then better for you than the carbs in wheat, sugar, rice, and processed foods. Protein is also more satiating so you'll be able to reduce meal frequency more easily, and even restrict calories more easily, if that is desirable. I lost 35 lb eating this way and never felt like I was on a 'diet' or excessively hungry, just like my weight 'normalized' as my blood sugars and hormones 'normalized'. But I don't think about myself as a sick person. While my endo labeled me a diabetic a colleague of mine who is a diabetologist said I am not a diabetic based on my blood sugar levels on my regular diet. Now, if I ate a different diet, my blood sugars would be high and I would be a diabetic. But, as long as I feed myself the foods I can metabolize correctly, my blood sugars are normal.
Having impaired glucose tolerance does not mean that you are insulin resistant. Impaired glucose tolerance can be caused by either insulin resistance, or insufficient insulin secretion. To find out, you need to get your doctor to monitor both insulin and glucose during an OGTT. From the ratio of glucose to insulin, it can be inferred how responsive your body is to insulin.
My problem is that I undersecrete insulin. The first clue was that my fasting insulin levels are below range although my fasting glucose was only marginally, if at all, elevated.. When I eat carbs (except small amounts of non starchy carbs from veggies), they make me sleepy, lethargic, and depress my body temperature. They also make my blood sugar go too high and stay too high for too long.