Read Atkins Diabetes Revolution Online
Authors: Robert C. Atkins
This chart provided with permission from INCIID, the InterNational Council on Infertility Information Dissemination, Inc. (www.inciid.org). Use of materials provided by INCIID is voluntary, and reliance on such materials should only be undertaken after consultation with a physician.
WHAT THE INSULIN NUMBERS MEAN
When your blood is drawn at the various intervals during the glucose tolerance test, the amount of insulin in your blood should be checked along with your blood sugar levels.
Insulin is measured in micro International Units per milliliter, or µIU/mL.According to the preceding chart, a normal fasting insulin level (also called fasting serum insulin) would be 10 µIU/mL or lower. Half an hour into a glucose tolerance test,normal insulin would rise to between 40 and 70 µIU/mL. (Note: Although the preceding chart lists a half-hour insulin level, Dr. Atkins felt he could obtain the information he needed by measuring the one- and two-hour levels.) According to the chart, at the one-hour mark, normal insulin would be between 50 and 90 µIU/mL. People with insulin resistance, however, will have insulin levels that are at least five times their fasting level. If you start out with a fasting blood insulin of 11, for instance, you have insulin resistance if your insulin level is 55 µIU/mL or more one hour after swallowing the glucose drink—even though that’s still in the normal range. According to the chart, no matter what your starting blood insulin, a level of 80 µIU/mL or more at the one-hour mark indicates insulin resistance.
By the two-hour point in the test, insulin levels usually begin to drop down again, falling into the 6- to 50-µIU/mL range. If your insulin level is still at 60 µIU/mL or more at this point, you have insulin resistance. Insulin level is a bit tricky to measure, and results will vary among testing labs. (The lab at which your tests are analyzed will report the normal range for
their
labs.)
Once you have reached stage 3,progression to stage 4 is inevitable if you make no lifestyle changes. In stage 4, the blood sugar rises to a higher than normal level as insulin resistance and high insulin production continue to worsen. This is where the GTT is especially valuable as compared with standard screening recommendations from the American Diabetes Association.
As part of a typical annual physical exam,your health care provider will probably check only your fasting blood sugar (FBS). Insulin levels are not routinely checked.At stage 4, however, it is likely that your FBS is still within the normal range.Getting the A-OK on your blood sugar gives you a false sense of security, allowing you to continue with the illusion that any extra pounds are purely a cosmetic problem.You won’t be able to see the effect of that fat storage on your body chemistry with the FBS test alone.
The FBS test doesn’t measure what happens to your blood sugar after a typical high-carb meal. Your real concern at this point should be excessive insulin and the silent damage that comes from high blood sugar.You are now making more fat and storing it in your body; at the same time, this storage process is clogging your arteries. Your blood pressure may be creeping up while endothelial dysfunction worsens. Also at this point many of you are finding it increasingly more difficult to control carbohydrate cravings.
If your doctor recognizes your risk of diabetes and wants to investigate further, he or she is likely to order a two-hour glucose tolerance test that will
not
include insulin measurements. The test will measure fasting and two-hour blood sugar levels, following an oral glucose challenge.If your blood sugar reading at the second hour falls between 140 mg/dL and 200 mg/dL, you have impaired glucose tolerance, or prediabetes. That’s useful knowledge, but it’s incomplete. Because your insulin levels weren’t checked,you won’t know how much insulin you are making, and therefore you don’t know how severe your metabolic abnormality really is.Your insulin numbers could be quite high, but because the two-hour test looks only at blood sugar, it misses this important finding.
Prediabetes is also diagnosed when fasting blood sugar is between 100 mg/dL and 125 mg/dL—above normal but not yet in the diabetic range. But the FBS test can be misleading at this stage in the progression. Based on the FBS, you can
look
like you have prediabetes, but in reality you already
have
Type 2 diabetes.
This was the case with Susan F.,a 53-year-old woman who had fasting blood sugar of 117 mg/dL, which is below the cutoff point of 126 mg/dL for diabetes. Her primary-care doctor had diagnosed her with hypoglycemia several years before and now told her she had prediabetes. She came to Dr. Atkins because, at five feet one inch and 260 pounds,weight loss was a priority for her.He was almost certain Susan had progressed beyond prediabetes, and the glucose tolerance test proved him right. Her blood sugar jumped to diabetic levels, and her insulin levels were among the highest he had ever seen. Her high insulin levels kept her from losing much weight at first, but after five months she was losing slowly but steadily and many of her other health issues were improving as well.
Another patient, Patricia G., could have avoided her diagnosis of diabetes had she only come to see Dr. Atkins earlier. When he first saw Patricia, she was five feet three inches and weighed 268 pounds. She had been diagnosed with the metabolic syndrome and was taking drugs to treat her high blood pressure and high blood lipids. Because there was a history of diabetes in her family, Dr. Atkins strongly suspected she had already moved well beyond the metabolic syndrome to diabetes, even though her fasting blood sugar was 111 mg/dL, still in the prediabetes range. The GTT showed he was right—she did indeed have Type 2 diabetes,and had probably had it for several years.She did extremely well once she started controlling her carbs. Over the next 11 months, she lost more than 20 pounds, her blood sugar came down, and so did her blood pressure and blood lipids.
As you can see, another virtue of the GTT is that it can detect “hidden” diabetes, as happened in this unusual case: Bernadette S. was a very large woman, standing six feet one inch and weighing 363 pounds. Someone who is that severely overweight (BMI of nearly 50) is almost certainly diabetic, yet because her fasting blood sugar was normal, her regular doctor never investigated any further. Dr. Atkins did and found that Bernadette’s GTT results clearly showed she had Type 2 diabetes. After five months of following the Atkins program, Bernadette had lost nearly 30 pounds. Her fasting blood sugar was normal, and her glycated hemoglobin (A1C)—see Chapter 7 for more details on this—was 5.1, an excellent reading that indicated her blood sugar had been at normal levels for the past three months.
The GTT is also useful for revealing the subtle changes that happen as you begin to creep up to the higher ranges of normal glucose or insulin values. Even a slight shift toward the high end of normal can be cause for concern, especially if you are also gaining weight, craving carbs, or have a family history of diabetes. Your blood sugar doesn’t suddenly change from normal to abnormal; rather, it’s like a water- color in which one color imperceptibly shades into another.
During his many years in clinical practice, Dr. Atkins learned to recognize these subtle changes and to use them as a tool in diagnosing blood sugar abnormalities, educating patients, and preventing illness. A test in the normal range does not necessarily mean that an individ ual is at his or her metabolic healthiest. When he reviewed the results of a GTT, in addition to looking at the values for each hour, Dr.Atkins looked at the pattern of change in blood sugar and insulin values, and also observed how the patient felt at various points over the course of the test.
Although there are normally accepted values that are used to analyze the results of the GTT (as indicated on the chart on page 66), Dr. Atkins did not see matters in such a black-and-white fashion. When seeing someone at risk for blood sugar problems, he certainly would have agreed with the commentary on the chart, but if a patient’s blood sugar rose much above 150 mg/dL after the glucose drink, Dr. Atkins would be alerted to the possibility of that patient’s having insulin/glucose metabolism abnormalities. The closer the blood sugar got to 200, the more concerned he would get. He also always took into consideration the symptoms the patient reported during the test.
The more symptoms the patient has,the more carb intolerant he or she is, even if the blood sugar and insulin numbers are not yet way out of line. The important point to remember is this: How you feel during the test reflects how much your body is stressed by the ups and downs in your insulin and blood sugar.
THE END GAME
If excessive demand for insulin caused by eating high-carb foods continues over a long period, the insulin-producing beta cells in the pancreas can become exhausted. They can no longer make enough insulin—or they may even stop making insulin altogether. This is stage 6 of Type 2 diabetes, and it now typically requires administering insulin to yourself for the rest of your life.Still,even when the disease has progressed this far, you can improve your situation. If you stop overloading your pancreas with carbohydrates, you may be able to restore some insulin production. By learning to control your carbs and making other lifestyle changes, you may be able to go off insulin completely or at least keep your dose to a minimum and avoid complications, such as hypoglycemic episodes, that often accompany insulin administration.
OTHER BLOOD TESTS
In addition to the GTT,Dr.Atkins would typically order:
As a cardiologist, he also screened for markers of cardiovascular risk, such as C-reactive protein (hs-CRP), homocysteine, lipoprotein(a), and fibrinogen. These tests are crucial for patients who have elevated lipids, hypertension, known heart disease, diabetes, or a strong family history of heart disease.We’ll discuss these risk factors in more detail in Chapter 9, The Cardiac Connection.
ARE YOU MAKING INSULIN?
If you have been newly diagnosed with diabetes,
stressing the system with a glucose tolerance test may not be appropriate.The key question is discovering how much insulin your pancreas is still producing. Does your pancreas produce high, normal, or low amounts of insulin? The answer is extremely important, as it can influence the kind of treatment you are given.
Instead of the GTT, Dr. Atkins would have these patients do a two-hour postprandial (after a meal) test.This is a way of determining how high your insulin and blood sugar go two hours after you eat a high-carb meal. To do the two-hour postprandial test, you fast for 12 hours (water is allowed) before the test. A blood sample is drawn for blood sugar and insulin. You then eat a standard high-carb breakfast as recommended by the American Diabetes Association: six ounces of orange juice, a bowl of plain oatmeal, two slices of toast, decaf coffee or tea sweetened with a teaspoon of sugar. Two hours after you finish the meal, blood is drawn again to measure sugar and insulin.
If the two-hour insulin level has at least doubled from the baseline level, your pancreas is still clearly producing insulin. That’s excellent news, because it means the ABSCP alone should be effective for managing your blood sugar. If the two-hour insulin level hasn’t doubled, this suggests that your insulin production is low. Don’t despair. You may well need medication or even supplemental insulin at this point, but the ABSCP will still be extremely helpful to you. Many of Dr. Atkins’ patients started the program needing diabetes medications and were able to reduce the doses or even stop taking the drugs completely. (We’ll discuss drug treatment for Type 2 diabetes in detail in the next chapter.)
THE C-PEPTIDE TEST
Another, somewhat indirect way to check your insulin production is a blood test for c-peptide. This protein is a normal by-product of insulin production, so your level of c-peptide is an indication of how much insulin your pancreas is making. Because the normal ranges may vary among laboratories, you should compare your results with the normal results reported by the lab you use. The higher above the norm your c-peptide level goes, the more hyperinsulinemic you are.
Krystal M. was only 19 years old when she first came to see me, but she already had a well-advanced case of the metabolic syndrome. At 5 feet 8
¾
inches tall, she weighed 288 pounds. Her c-peptide blood level was 9.8 ng/mL (more than twice the normal range), her triglycerides were 180, her total cholesterol was 182, her HDL was 33, her fasting blood sugar was 95, and her A1C was 5.6. In addition, she required two medications that made it difficult to manage her weight. Nine months after beginning her controlled-carb program, Krystal had lost 40 pounds and 5
¼
inches from her waist. Her lab values improved: her c-peptide was normal at 3.6 ng/mL, her triglycerides were 161, her total cholesterol had dropped to
161, her HDL was 35, her LDL was 113, her fasting blood sugar had dropped to 78, and her A1C was 4.6. At the two-year point, Krystal weighed 186, and she had lost 15
¼
inches at her waist. Her lipid lab values had also continued to improve, with triglycerides of 109, total cholesterol of 143, HDL of 56, and LDL of 65.
—M
ARY
V
ERNON
While the c-peptide test does reflect insulin production in the body, unlike the GTT performed by Dr. Atkins, it does not measure the glucose response to the insulin that is present.
DIET OR DRUGS?
If you are diagnosed with Type 2 diabetes, the chances are good that your doctor will immediately prescribe at least one drug to control your blood sugar. If you’re not already taking medications for high blood pressure and high blood lipids, chances are good you’ll be prescribed those drugs as well. And then your doctor will probably hand you a booklet that describes the American Diabetes Association (ADA) diet for people with Type 2 diabetes. You’ll be urged to follow this low-fat, high-carb approach—in fact, your health insurance company may even pay for you to attend classes that teach you all about this “healthy”diet.