A Christian Guide to Body Stewardship, Diet and Exercise

Chapter 2: Basic Nutrition 22 categorizes it as a low GL food. Conversely, a candy bar has a GL rating of 25 (GI rating of 62 x 40 g of sugar per serving / 100), which categorizes it as a high GL food. As you can see from this example, GL is likely the better and more accurate means for assessing and choosing foods containing carbohydrate. Table 2.5 provides the various GI and GL classifications. Appendix A provides the GI and GL ratings for several common foods (Foster-Powell et al., 2002). Table 2.5. Classifications for Glycemic Index and Glycemic Load High Medium Low Glycemic Index 70-100 55-69 0-55 Glycemic Load ≥ 20 11-19 ≤ 10 Protein Similar to carbohydrates, protein also plays an important role within the body. For example, protein is used to build and repair various bodily tissues, support numerous metabolic reactions as well as maintain proper pH and fluid balance. The AMDR for protein is 10-35% of total calories. Protein can be found in a variety of foods with the largest quantities being found in animal products (e.g., meat, poultry and dairy). Whole grains, beans, legumes, nuts and seeds are also good sources of protein. Proteins are made up of smaller compounds called amino acids. There are 20 different amino acids: 9 essential, 7 conditional and 4 nonessential. Essential amino acids, also known as indispensable amino acids, cannot be produced by the body and therefore must be supplied through the diet. Conditional amino acids are usually not essential except during times of illness or stress. Nonessential amino acids can be made by the body and thus do not need to be provided in the diet. Table 2.6 provides a comprehensive listing of the different essential, conditional and nonessential amino acids. Table 2.6. Essential, Conditional and Nonessential Amino Acids Essential Amino Acids Conditional Amino Acids Nonessential Amino Acids Histidine Phenylalanine Lysine Arginine Proline Alanine Isoleucine Threonine - Asparagine Serine Aspartic Acid (Aspartate) Leucine Tryptophan - Glutamine Tyrosine Cysteine Methionine Valine - Glycine - Glutamic Acid (Glutamate)