ABSTRACT
Key Points ...................................................................................................................................... 157 Introduction .................................................................................................................................... 158 Glucose Metabolism ...................................................................................................................... 159 Glucose Metabolism in the Fed State ............................................................................................ 159
Oxidative Glucose Metabolism ................................................................................................. 159 Nonoxidative Glucose Metabolism ........................................................................................... 160 Pentose Phosphate Pathway ...................................................................................................... 160
Short-term Fasting and Starvation ................................................................................................. 161 Glycogenolysis .......................................................................................................................... 161 Gluconeogenesis ....................................................................................................................... 161
Glucose Cycling Associated with Exercise .................................................................................... 161 Regulation of Glucose Metabolism ............................................................................................... 162 Hormonal Regulation ..................................................................................................................... 162 Allosteric Regulation ..................................................................................................................... 163 Organ-specic Glucose Metabolism .............................................................................................. 163 Fructose Metabolism ...................................................................................................................... 163 Effects of Fructose on Blood Glucose ........................................................................................... 165 Effects of Fructose on Lipid Metabolism ...................................................................................... 165 Galactose Metabolism .................................................................................................................... 165 Sugar Alcohol Metabolism ............................................................................................................ 166
Sorbitol ...................................................................................................................................... 166 Xylitol ....................................................................................................................................... 167
Conclusions .................................................................................................................................... 167 References ...................................................................................................................................... 167
• Fructose and galactose, unlike glucose, cannot be directly used as energy substrates by many cells of the organism; it needs rst to be converted into glucose, lactate, and fatty acids in splanchnic organs for fructose, into glucose in the liver for galactose.
