Figure 4.1: Carbohydrate Is Made by Photosynthesis
The sun’s energy becomes part of the glucose molecule—its calories, in a sense. In the molecule of glucose on the leaf here, black dots represent the carbon atoms; bars represent the chemical bonds that contain energy.
Figure 4.2: How Monosaccharides Join to Form Disaccharides
Single sugars are monosaccharides, while pairs of sugars are disaccharides.
Figure 4.3: How Glucose Molecules Join to Form Polysaccharides
Figure 4.6: Characteristics, Sources, and Health Effects of Fibers
Figure 4.7: One Way Fiber in Food May Lower Cholesterol in the Blood
Figure 4.8: Diverticula
Diverticula are abnormally bulging pockets in the colon wall. These pockets can entrap feces and become painfully infected and inflamed, requiring hospitalization, antibiotic therapy, or surgery.
Figure 4.9: A Wheat Plant and a Single Kernel of Wheat
Figure 4.10: Nutrients in Whole-Grain, Enriched White, and Unenriched White Breads
Table 4.6: A sampling of Whole Grains
If some of these sound unfamiliar, why not try them? Other cultures value them, and they could become your favorites, too.
Table 4.6: A Sampling of Whole Grains
If some of these sound unfamiliar, why not try them? Other cultures value them, and they could become your favorites, too.
Figure 4.11: Bread Labels Compared
Figure 4.12: How Carbohydrate in Food Becomes Glucose in the Body
Table 4.7: Lactose Intolerance Strategies
People with lactose intolerance can experiment with milk-based foods to find a strategy that works for them. The trick is to find ways of splitting lactose to glucose and galactose before a food is consumed, rather than providing a lactose feast for colonic bacteria.
Fig 4.13: The Breakdown of Glucose Yields Energy and Carbon Dioxide
Cell enzymes split the bonds between the carbon atoms in glucose, liberating the energy stored there for the cell’s use. 1. The first split yields two 3-carbon fragments. The two-way arrows mean that these fragments can also be rejoined to make glucose again. 2. Once they are broken down further into 2-carbon fragments, however, they cannot rejoin to make glucose. 3. The carbon atoms liberated when the bonds split are combined with oxygen and released into the air, via the lungs, as carbon dioxide. Although not shown here, water is also produced at each split.
Figure 4.15: Blood Glucose Regulation—An Overview
The pancreas monitors blood glucose (blue hexagons) and adjusts its concentration with two opposing hormones, insulin and glucagon. When glucose is high, the pancreas releases insulin which stimulates body tissues to take up glucose from the bloodstream. When glucose is low, it releases glucagon, which stimulates the liver to release glucose. When glucose concentration is restored to the normal range, the pancreas slows its hormone output in an elegant feedback system.
Table 4.8: Glycemic Index of Selected Foods.
Table 4.8: Glycemic Index of Selected Foods.
Figure C4.1: Increases in Adult Body Weight over Time
Figure C4.2: Daily Energy Intake over Time
Carbohydrates, and mostly added sugars, account for almost all of the increase in energy intakes during this period. The recent dip in calorie intakes parallels a slight reduction in added sugar intakes and a slowing of the rate of increase in obesity prevalence.
Figure C4.3: Sources of Added Sugars in the U.S. Diet
Most people are unaware of how much added sugar they consume in foods and beverages.
Figure C4.4: Glucose and Fructose in Common Added Sugars