Alcohol and Nutrition Highlight 7

What is alcohol? Contains 2 carbons One OH group Chemical name: ethanol or ethyl alcohol Can provide 7 kcal/g Lipid solvent

Where does alcohol come from? Fermentation Sugars (in presence of yeast, anaerobic conditions)  ethanol + ATP + water Sugars from grapes—wine Maximum alcohol percentage 10-12%

Distillation Organic lab technique use to separate liquids based on their boiling points Effectively concentrates alcohol in product Up to 90% alcohol Source of sugars dictates type of liquor Potatoes  vodka, agave  tequilla, grapes  brandy, sugar cane  rum

Expression of alcohol concentration Usually use proof system Proof = 2 x % A 15% alcohol solution would be 30 proof A 90% alcohol solution would be 180 proof

Alcohol in the body: digestion None required

Alcohol in the body: absorption Stomach (in men up to 20%) Small intestine Is water soluble—goes into blood stream and then to liver

Alcohol in the body: metabolism Get priority in body—red carpet treatment ADH MEOS Catalase

ADH system (1) The major system--- metabolizes about 90% of alcohol ingested Ethanol (ADH 1 )  acetaldehyde Acetaldehyde (ADH 2 )  acetic acid Acetic acid  acetyl CoA Acetyl CoA  CO 2 + H 2 O + ATP

ADH system (2) This takes place in stomach and liver cells (liver can convert up to ½ oz./hour) Acetaldehyde buildup causes sickness, intoxication Drug blocks ADH 2 —anabuse (disulfiram) Genetically different people have varying amounts of ADH 2

MEOS system Microsomal ethanol oxidizing system Overflow pathway Same reactions as ADH, different enzymes Enzymes are inducible (grow— tolerance) Interferes with drug degradation

Figure 8.2

Catalase system Very minor pathway Occurs in peroxisomes in liver

Alcohol in the liver Shift to acidosis Impaired gluconeogenesis Ketosis Altered protein metabolism Increased fat synthesis (clogs) Fibrosis Cirrhosis

Pg 281

Alcohol in the brain Narcotic Sedates inhibitory nerves CNS depressant Inhibits ADH synthesis Effects on brain structures (in order) Frontal lobe-reasoning (blue) Midbrain—speech and vision (above orange) Cerebellum—voluntary muscle movement (pink) Pons, medulla—respiration, heart action (orange)

Benefits of alcohol consumption Limited to moderate intakes—defined as one drink per day Pleasurable Lower heart disease risk

Risks of alcohol consumption Alcoholism is the third leading cause of preventable death in North America Fatalities 20% boating 23% suicides 39% traffic 40% house fires 47% homicides 65% domestic violence Contributes to 5 of 10 leading causes of death Obesity Malnutrition Inadequate food intake Impaired nutrient absorption Direct toxicity Werkicke-Korsakoff Syndrome

Additional problems Unemployment Accidents STD Unplanned pregnancy Fetal alcohol syndrome

Alcoholism 2 phase problem Problem drinking Addiction Signs of alcoholism table H7-4, p. 237

Treatment Best treated by combination of psychotherapy (such as AA) and drugs Anabuse—blocks ADH 2, makes drinker very sick Revia—naloxone blocks endorphine receptor in dopamine pathway—pleasure, blocks high Campral—activates GABA, reduces distress and discomfort like sweating and anxiety—used to help maintain abstinance Early intervention—60% success rate—takes at least 2 years Later in illness—success rate is not good