counting has grown in popularity as a meal planning approach in the United States since the completion of the Diabetes Complications and Control Trial (DCCT), in which carbohydrate counting was effectively used (Anderson et al. 1993; DCCT 1993). However, carbohydrate counting has been in use internationally since insulin was discovered and has been the meal planning method of choice in the United Kingdom for years (McCulloch et al. 1993).
Carbohydrate Counting has become popular for several reasons. First, the priority of achieving and maintaining glycemic control to decrease morbidity and mortality from diabetes complications has gained greater importance due to the results of the DCCT (DCCT 1993) and the United Kingdom Prospective Diabetes Study (UKPDS) in people with type 2 diabetes (UKPDS 1998). According to the American Diabetes Association’s (ADA) most recent nutrition recommendations and interventions, control of blood glucose to achieve glycemic control is a primary goal of diabetes management (ADA 2008b). Second, more attention is now focused on postprandial blood glucose control (Parkin and Brooks 2002) because of the finding that it is more strongly associated with the risks for atherosclerosis than preprandial blood glucose (Temelkova-Kurktschiev 2000). People with diabetes have defects in insulin action, insulin secretion, or both, and insulin defects impair the regulation of postprandial glucose in response to carbohydrate intake. The quantity and the type/source of carbohydrate intake are the major determinants of postprandial glucose levels (ADA 2008b). Interventions to help people accurately count and control their carbohydrate intake are important to help improve postprandial glycemic control.
The ADA suggests that carbohydrate counting is one method of meal planning that can help people match their doses of some blood glucose—lowering medications, such as insulin and/or insulin secretagogues, to carbohydrate consumption (ADA 2008b). Further, the Dose Adjusted for Normal Eating (DAFNE) trial conducted in Great Britain demonstrated a 1% lowering of A1C in people with type 1 diabetes who received training in adjusting mealtime insulin based on the carbohydrate consumed (DAFNE Study Group 2002).
RECOMMENDATIONS FOR
CARBOHYDRATE CONSUMPTION
Total carbohydrate
The following is a brief review of the current ADA recommendations regarding the consumption of carbohydrate within the framework of a healthy eating plan (ADA 2008b). More extensive reviews can be found (ADA 2008b; Sheard et al. 2004). Regarding the percent of calories that carbohydrate should contribute to the mix of macronutrients, the ADA states that “it is unlikely that one such combination of macronutrients exists that is optimal for all people with diabetes” (ADA 2008b). The ADA recommendations suggest that people seek guidance from the Institute of Medicine’s Dietary Reference Intakes (DRIs) (Institute of Medicine 2002). The DRIs recommend that adults should consume 45–65% of total energy from carbohydrate to meet the body’s daily nutritional needs while minimizing risk for chronic diseases.
The ADA supports the use of either low-carbohydrate or low-fat calorie-restricted diets for short-term use in people with diabetes. For longer term use, the ADA continues to raise questions about the long-term metabolic effects of very low—carbohydrate diets, which eliminate many foods that are important sources of energy, fiber, and other essential nutrients (ADA 2008b). The DRIs indicate that the minimum adult requirement for carbohydrate to provide adequate glucose for the central nervous system without reliance on protein or fat is 130 grams per day (Institute of Medicine 2002; Sheard et al. 2004). The ADA recommends, as do the DRIs, that good health can be achieved with a pattern of food intake that includes carbohydrate from fruits, vegetables, whole grains, legumes, and low-fat milk (ADA 2008b; Institute of Medicine 2002). It is worth noting that contemporary patterns of food intake are often lacking in foods from these groups (U.S. Department of Health and Human Services 2005). The remainder of calories can be contributed by 20–35% from fat and 10–35% from protein (Institute of Medicine 2002).
Amounts and types of carbohydrate
As noted above, the ADA nutrition recommendations suggest that carbohydrate intake, both the quantity and the type or source of carbohydrate, is the major determinant of postprandial glucose levels (ADA 2008b). With this stated, it should be noted that the ADA recommendations now reflect that the use of the Glycemic Index (GI) and Glycemic Load (GL) as a means to assess the glycemic impact of a food on blood glucose can provide a modest additional benefit over that observed when just total carbohydrate is considered (ADA 2008b). The concepts of GI and GL are discussed further in chapter 10, along with other dietary components that impact blood glucose levels, including fiber, polyols, protein, and fat.
CHAPTER TWO
Assessing
Knowledge
and Skills
The choice to use carbohydrate counting as a meal planning approach should be based on several factors about each individual, including but not limited to
• Existing knowledge of meal planning and diabetes management self-management
• Willingness and ability to learn and use the necessary skills
• Diabetes management needs and desires
These same factors will indicate whether a person should progress from Basic to Advanced Carbohydrate Counting (see chapter 6).
ASSESSING A PERSON’S KNOWLEDGE AND SKILLS
Before beginning carbohydrate counting education, it is essential to determine a person’s base knowledge. When working with a person with newly diagnosed diabetes or new to carbohydrate counting, assess the following:
• Knowledge of the goals for healthy eating in general
• Knowledge of the goals for healthy eating with diabetes
• Preconceived notions of what a person with diabetes should or should not eat, as well as understanding about the timing of meals and snacks
• Understanding of basic nutrition concepts, such as:
• Understanding of blood glucose—lowering medication(s)—onset, action, duration, and mechanism(s) of action(s)
People with diabetes are referred for medical nutrition therapy (MNT) at varying points in their life and management of diabetes. For this reason, it is important to realize that just because a person has had diabetes for many years or claims to have learned or used carbohydrate counting, doesn’t mean that they have and/or are able to apply the above knowledge and/or that this knowledge is up to date as diabetes nutrition recommendations have evolved.
Methods for assessment
Since many diabetes educators teach Basic Carbohydrate Counting in a group setting, it is important to develop methods that assess
