Sunday, January 24, 2016

Type 2 Diabetes, a Dietary Disease #312: Isn’t your Very Low Carb WOE…well, extreme?

A person who is neither Pre-Diabetic nor a clinically diagnosed Type 2 invariably asks me, “Isn’t your Very Low Carb (VLC) eating program…extreme?” In a word my answer is, “yes.” I am highly Insulin Resistant (IR); therefore, I am Carbohydrate Intolerant. Carbs are “poison” for me. However, IR is a relative term; it is on a scale measured in percentage; its inverse (1/IR) is Insulin Sensitivity, a measure of how well your cells take up glucose carried in your blood by insulin. And the degree to which you are Insulin Resistant will determine how many carbohydrates you can safely eat. The determining factor for you will be your degree of IR/Carbohydrate Intolerance.
How does the “treatment-naïve” (untreated) patient with a slightly elevated fasting glucose or hemoglobin A1c determine the degree of IR/Carbohydrate Intolerance they have developed? Well, there are laboratory tests, like the IGTT or Impaired Glucose Tolerance Test. Upon my diagnosis 30 years ago, my GP sent me to an Endo who ordered this 2 hour test in a hospital outpatient setting. It confirmed the GP’s preliminary diagnosis: I had T2DM. At the time (1986), the prevailing clinical standard for an office diagnosis of frank Type 2 Diabetes was 2 consecutive visits with a Fasting Blood Glucose (FBG) ≥ 140mg/dl. In 1996 the standard changed to ≥ 126mg/dl.
There’s also the HOMA2 that I once asked an endocrinologist to do for me. He said he had read about in being used in research but had never ordered it. He did though, for me. It included a fasting serum insulin and gave a 2-part result: Insulin Sensitivity (the inverse of IR) and Beta Cell Function. Beta cells make insulin in the pancreas. I had been eating VLC for years, so my result was remarkably good: Beta cell function = 68.2% and Insulin Sensitivity (IS) = 94.6% (IR = 1.057). This supports the hypothesis that eating VLC (and exercise) increase IS, and that the unstressed pancreas of Type 2s can still possibly create new beta cells. I can only imagine how poor my beta cell function would be today, and how high my IR would be, if I were still eating what “the doctor ordered.”
Today, while the Fasting Blood Glucose test is still in common use, the new diagnostic standard is the A1c test. It measures the percentage of glucose on the surface of your red blood cells. Since red blood cells have an average life of about 3 months, this test is a better measure of the rise and fall of your blood sugar 24/7 for a longer time. It also captures the after-meal spikes which are a better measure of Insulin Resistance/Carbohydrate Intolerance than a simple fasting measurement. Both the A1c and fasting glucose lab tests are “convenient” (inexpensive).
But be careful. This is the point I described in Type 2 Diabetes, a Dietary Disease #306. You are at a juncture. If you leave the matter of “what's next?” entirely up to your “treatment team,” including clinician and RD or CDE, after you fail to lose weight following advice to “eat a balanced diet and exercise,” your clinician will treat your symptom (high blood glucose) by prescribing a pill (or pills) to lower your blood sugar. As such, so long as you continue to eat a balanced diet, the cause of your elevated blood sugars will not be addressed, and your disease will progress! The cause is the Insulin Resistance that has resulted in your becoming Carbohydrate Intolerant and Pre-Diabetic or a Type 2.
This errant course of treatment is in part based on the erroneous belief that being overweight or obese caused your Type 2 Diabetes. That’s one reason your doctor wants you to lose weight. But, in fact, the opposite is true. Read Type 2 Diabetes, a Dietary Disease #308 for an explanation of “What Causes Type 2 Diabetes.” Insulin Resistance is the the actual precipitating cause of Type 2 Diabetes, and it causes obesity. Insulin Resistance, for us who are genetically predisposed, is “expressed” through a diet that is composed of excessive carbohydrates.
So, the only course of “treatment” that treats the cause of Pre-Diabetes or Type 2 Diabetes is one that reduces the carbohydrates in your diet. The government sanctioned dietary pattern (reference the HHS/FDA Nutrition Facts Panel: Footnote 5) is 60% (300g) carbs, 10% (50g) protein and 30% (65g) fat (% by calories, not grams). On a 2,000 kcal/day diet, a Low Carb dietary pattern could be 20% carb, 20% protein, 60% fat; that would be 100 grams of carbohydrate a day. This is not so “extreme,” yet it is only 1/3rd what is recommended, and a 2/3rds reduction. Or even say 10% carb (50g/day), 20% protein and 70% fat. Either plan would be a huge improvement and would almost certainly reverse a Pre-Diabetes condition, putting the condition in “remission,” so long as you continued to eat no more than 100g (or 50g) of carbs a day. Remember, IR is on a scale, and everyone’s varies.

Of course, if you’re “healthy” (i.e. not Pre-Diabetic or a Type 2, and not yet genetically “expressed” but a little thick around the middle), you could probably stay healthy, and lose the extra weight, if you ate 40% carbs, 20% protein and 40% fat. That’s 200 carb g/d and still a 1/3rd reduction from the 300g (60% carb) government plan.

No comments:

Post a Comment