By Doris Dickson for Diabetes1 Reviewed by Dr. Mike Fuller, MD
Carbohydrate counting, otherwise known as “carb counting,” is the technique by which insulin-dependent diabetics determine their insulin requirements for meals. On the face, it is a simple enough task. A person with diabetes counts the number of carbs they plan to eat, take a pre-determined carb to insulin ratio, then multiply and inject.
However, not all carbs are equal and protein is not “free;” it does affect blood sugar levels. Carbs have variable digestion rates that often do not match insulin absorption and action rates. In addition, fat and protein slow down the digestion rate of the entire meal, often exceeding the duration of today’s speedy rapid-acting insulin products (Apidra, Humalog and Novolog) and even the legacy intermediate-acting Regular insulin.
In addition, protein, and to a lesser degree, fat, still convert to some glucose in the digestion process. Protein, according to Dr. Richard Bernstein, converts to approximately 36 percent glucose, albeit it much more slowly than carbohydrates. In diabetes classes in 1976, the Joslin Clinic taught there is also an approximately 10-15 percent conversion of fat to glucose. Failure to include protein (and fat) in the insulin dose calculation results in improper and improperly timed dosing.
Further, the fallacy that protein is “free” results in a variety of glucose management challenges. People with diabetes confidently do the math for their meal insulin dose. They inject the insulin they estimate they need but, in the end, scratch their heads. They assume they have done something wrong. A variety of circumstances may arise including:
- Low blood sugar when the rapid acting insulin starts to peak followed by high blood sugar hours later.
- “In target” blood sugar at the two-hour point followed by high blood sugar several hours later.
In the short-term, people with diabetes take a corrective insulin injection of rapid or intermediate acting insulin to reduce the high blood sugar. In the long-term, they and their caregivers often incorrectly conclude the problem lies in their long-acting insulin (“basal”) requirements and erroneously increase Lantus, Levemir or NPH doses.
Since “basal” insulin requirements are not the root of the problem, these people can then have a completely new set of challenges. They begin “overdosing” basal insulin. That is a partial problem for a variety of reasons including:
- Unnecessarily high basal doses forcing someone to eat the same amount of the same type of food every day at the same time in order to match up to the basal insulin requirements.
- Low blood sugar often resulting when the patient does not eat meals of the same volume and type are not eaten at the same time.
- “Eating to one's insulin” which frequently results in overeating and weight gain especially if they are having frequent middle of the night bouts of low blood sugar.
- Reduced insulin sensitivity – a result of taking, or the body producing larger than necessary insulin amounts
- Now that the basal rates are inaccurate, so too are the carb to insulin and correction ratios.
A vicious circle begins. Not surprisingly, someone who is unable to reach a target blood sugar level also becomes frustrated. So, how can an insulin-dependent diabetic more accurately dose for a well-rounded meal, complete with carbohydrates, protein and fat?
Continued in Part 2.
Dr. Bernstein’s Diabetes Solution – The Complete Guide to Achieving Normal Blood Sugars by Richard K. Bernstein, MD
The Insulin Resistance Diet by Cheryle R. Hart, MD and Mary Kay Grossman, RD