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Chapter 4a presents the following content: History of alcohol use, the character of alcohol, alcohol: is it a nutrient? alcohol and its sources, alcohol absorption, alcohol in the body, when alcohol becomes a problem, fetal alcohol spectrum disorders, alcoholics and malnutrition, does alcohol have benefits?
Spotlight on Alcohol The Character of Alcohol • Ethanol – The alcohol in beer, wine, spirits • Methanol – Wood alcohol—poisonous Alcohol: Is it a Nutrient? • Provides energy – kcal/g • No other nutritive value Alcohol and Its Sources • Fermentation – Yeast cells metabolize sugar to make alcohol • Alcoholic beverages – Beer: 5–6% alcohol – Wine: 8–14% alcohol – Liquor: 35–45% alcohol • “Proof” is twice the alcohol percentage Alcohol Absorption • No digestion required • Absorbed from mouth, esophagus, stomach, and small intestine • Absorption slowed by food • 80–95% of alcohol is absorbed unchanged Alcohol in the Body • Metabolizing small amounts of alcohol – Alcohol dehydrogenase • Alcohol acetaldehyde – Aldehyde dehydrogenase • Acetaldehyde acetate – Acetaldehyde, acetate converted to acetyl CoA • Acetyl CoA molecules built into fatty acids Alcohol in the Body • Metabolizing large amounts of alcohol – Overwhelms alcohol dehydrogenase system – Uses microsomal ethanol-oxidizing system (MEOS) Alcohol in the Body • Removing alcohol from circulation – Liver metabolism limited – Blood alcohol level falls slowly Alcohol in the Body • Individual differences in rate of alcohol metabolism – Gender – Race/ethnicity – Age When Alcohol Becomes a Problem • Alcohol in the brain and nervous system – Depressant; affects all parts of brain • Alcohol’s effect on GI system – Esophagitis and gastritis When Alcohol Becomes a Problem • Alcohol and the liver – Fatty liver – Fibrosis – Cirrhosis • Fetal alcohol syndrome – Physical abnormalities – Mental retardation – Low birth weight and poor growth Fetal Alcohol Syndrome • Can have a devastating impact when consumed during pregnancy • Variety of congenital defects: - Mental retardation - Coordination programs - Heart, eye, and genitourinary malformations - Slowed growth rates Alcoholics and Malnutrition • Poor diet – Alcohol provides energy but no nutrients – Economic factors – Lack of interest in food; GI problems Alcoholics and Malnutrition • Vitamin deficiencies – Alcohol interferes with vitamin metabolism – Folate, thiamin, and vitamin A • Mineral deficiencies – Inadequate diet; fluid losses – Calcium, magnesium, iron, and zinc – Some mineral levels are elevated Alcoholics and Malnutrition • Macronutrients – Alcohol interferes with amino acid absorption – Alcohol raises blood levels of fats • Body weight – Inconsistent effect of alcohol calories on weight Does Alcohol Have Benefits? • Moderate drinking has been associated with reduced mortality • Heart disease – French paradox: red wine Does Alcohol Have Benefits? • People who should not consume alcohol: – Those who cannot moderate their intake – Children and adolescents – Those taking certain medications – Those with illnesses worsened by alcohol – Those who drive or operate machinery – Pregnant or breastfeeding women – Those with a strong family history of alcoholism ... Variety of congenital defects: - Mental retardation - Coordination programs - Heart, eye, and genitourinary malformations - Slowed growth rates Alcoholics and Malnutrition • Poor diet – Alcohol provides... Fermentation – Yeast cells metabolize sugar to make alcohol • Alcoholic beverages – Beer: 5–6% alcohol – Wine: 8–14% alcohol – Liquor: 35–45% alcohol • “Proof” is twice the alcohol percentage Alcohol. .. – Calcium, magnesium, iron, and zinc – Some mineral levels are elevated Alcoholics and Malnutrition • Macronutrients – Alcohol interferes with amino acid absorption – Alcohol raises blood levels