AlcoholAlcohol

“Beer is proof that god loves us and wants us to be happy.”

-Benjamin Franklin

History of alcoholHistory of alcohol

• Old religious and medical writings frequently recommended its use

• Lifts spirits, ease boredom, numb hunger, dull discomfort

• People value alcohol for its analgesic

and euphoric qualities

History of Alcohol

• 6400 BC: Neolithic people produced berry wines

• 4000 BC: Sumerians fermented grains and cereals, producing beer, date wine and other alcoholic beverages

• Ancient Egyptians recorded >100 medical prescriptions for alcohol

• Babylonians developed >20 different types of beer

Alcohol: Alcohol: definitiondefinition

• Organic compound with one or more –OH groups

• The alcohol found in beer, wine or spirits is technically called ethyl alcohol or ethanol

• Ethanol is able to cross the blood-brain barrier

Alcohol: Alcohol: definitiondefinition

• Alcohols are lipid solvents – their ability to dissolve lipids out of cell membranes allows alcohol to penetrate rapidly into cells, destroying structures, and killing the cell in the process

• Therefore, alcohols are toxic, but they can also be used to kill microbial cells

Alcohol: Alcohol: definitiondefinition

• Ethanol is less toxic than other alcohols

• If it is sufficiently diluted, and taken in small enough quantities, it can produce the effect that people seek with a low enough risk to be tolerable

• Used in this way, alcohol is a drug

• Like all drugs, it offers benefits and hazards

Binge drinking: consumption of 5 or more alcoholic drinks on one occasion

Alcohol consumption

• Described as “drinks per day”– Drink: the amount of a beverage that provides .5 fluid

oz. of ethanol

– Typically, equivalent to:• 1.5 oz. of distilled spirits (80 proof)

• 4-5 oz. of wine

• 10 oz. of wine cooler

• 12 oz. of beer

Alcohol content (by volume) of beer and wine

• Non-alcoholic beer 0.5%

• “Light” beers 3-4%

• Regular beers 5%

• Stouts, malt liquors,

specialty beers 7%

• Wines 7-24%

Proof

• The alcohol content of distilled spirits is related directly to its proof.

– 100 proof is 50% alcohol

– 80 proof is 40% alcohol

Alcohol in the body

• Does not require digestion

• Absorbed from both the stomach and jejunum

• From the mucosal cells, transported by portal vein to the liver

• In liver, is metabolized or released into bloodstream

• In bloodstream, is rapidly distributed through body’s intra- and extra-cellular spaces

Factors affecting absorptionFactors affecting absorption

• Amount Amount

• SpeedSpeed

• Presence/Absence of foodPresence/Absence of food

• CarbonationCarbonation

• Gender/Individual differencesGender/Individual differences

• Genetic factors/Individual differencesGenetic factors/Individual differences

Individual Differences in Alcohol Individual Differences in Alcohol MetabolismMetabolism

Affected by:

• Levels of alcohol dehydrogenaseLevels of alcohol dehydrogenase

• Body size Body size - smaller livers

• Body Composition Body Composition – less water to dilute alcohol

• Hormonal fluctuations Hormonal fluctuations – heightened response to alcohol during menstruation, or when taking birth control pills

Oxidation of Alcohol begins in the Oxidation of Alcohol begins in the StomachStomach

• Oxidation of alcohol occurs primarily in liver, small amount occurs in stomach through the action of two enzymes:

(1) Alcohol dehydrogenase (ADH)(2) Aldehyde dehydrogenase (ALDH)

For more chronic alcoholics there is a third pathway:

(3) Microsomal ethanol oxidizing system

Alcohol in the body: Small Alcohol in the body: Small IntestineIntestine

• Alcohol is also rapidly absorbed in the SI

• It gets absorbed and metabolized before most nutrients

• This priority status helps to ensure a speedy disposal and reflects two facts:

1. Alcohol cannot be stored in the body2. Alcohol is potentially toxic

Oxidation of Alcohol in LiverOxidation of Alcohol in Liver• Liver cells are the only other cells in the body that

make enough ADH to metabolize alcohol at an appreciable rate

• Alcohol dehydrogenase (ADH) catalyzes the conversion of alcohol to acetaldehyde (which is toxic)

• Then, aldehyde dehydrogenase (ALDH) quickly converts acetaldehyde to acetate

• “Antabuse” deliberately blocks conversion of acetaldehyde to acetate

Alcohol metabolismAlcohol metabolism

Alcohol metabolismAlcohol metabolism

• Majority of alcohol metabolism occurs in the liver, which contains significant amounts of ADH and ALDH.

• The maximum rate of alcohol breakdown is set by the amount of ADH available and its activity level

Alcohol Effects:Alcohol Effects: Brain Brain

• 1. Alters reasoning and judgment, depresses inhibitions (A)

• 2. Speech and vision (C and D)

Alcohol Effects:Alcohol Effects: Brain Brain

• 3. Voluntary muscle control, impairs motor skills (B, C, D, E)

• 4. Conscious brain is completely subdued, and the person passes out

• Brain cells die with excessive exposure to alcohol. Not all brain cells can regenerate (unlike liver cells)

• Some heavy drinkers suffer permanent brain damage

Alcohol effects: Alcohol effects: BrainBrain

Alcohol effects: Brain

• Korsakoff psychosisKorsakoff psychosis• Characterized by ongoing memory and learning

problems

• Wernicke-Korsakoff syndromeWernicke-Korsakoff syndrome• Form of alcoholic encephalopathy• Linked to severe thiamine deficiency• Potentially fatal, occurs with alcohol-related

liver failure

Alcohol Effects:Alcohol Effects: Liver Liver

• Toxic to liver cells• Alters metabolism of

nutrients and drugs• Impairs ability to store

nutrients

Alcohol EffectsAlcohol Effects: The Liver: The Liver

• The earliest evidence of liver damage is fat accumulation

• Fatty liver can appear after only a few days of heavy drinking, and recedes with abstinence

• The liver can increase in weight from ~ 3 pounds, to over 10 pounds

• What causes the liver to become fatty?

Alcohol EffectsAlcohol Effects: The Liver: The Liver

• With regular, high intakes of alcohol, the liver becomes chronically inflamed (alcoholic hepatitis)

• The hepatitis may be treatable, but it is often fatal

• With continued inflammation, the liver becomes fibrous, and scarred: Cirrhosis

• About 10-20% of heavy drinkers develop cirrhosis

Alcohol Effects:Alcohol Effects: Upper GI Upper GI

• Carcinogenic to upper GI cells

• Increases gastric acid production

• Inflames lining of stomach

• Increases the likelihood of reflux, gastritis, and esophagitis

Alcohol Effects:Alcohol Effects: Pancreas Pancreas

• Toxic to pancreatic cells

• Impairs digestion and absorption

• Alters secretion of pancreatic hormones

• Increased risk for pancreatitis, which reduces digestive enzyme production

The HangoverThe Hangover

• Symptoms can include• pounding headache• Fatigue• muscle aches• Nausea• stomach pain• heightened sensitivity to light and sound • Dizziness• possibly depression, anxiety, and irritability

CausesCauses

• DehydrationDehydration: dry mouth and headache

• Irritation of stomach and intestinesIrritation of stomach and intestines: nausea, stomach pain, vomiting

• HypoglycemiaHypoglycemia: fatigue, light-headedness

• Disruption of sleep patternsDisruption of sleep patterns: fatigue

• CongenersCongeners

CongenersCongeners

• Impurities produced during fermentation or metals such as zinc that are added to certain sweet liqueurs in order to enhance flavor.

• They contribute to the distinctive smell of the beverage and may increase intoxicating effects and subsequent hangover

• Found in: whisky, red wine, brandy

““Curing” A HangoverCuring” A Hangover

• The most effective treatment is TIMETIME

Others:• SleepSleep• Drinking hydrating beveragesDrinking hydrating beverages• EatingEating• AntacidsAntacids• AspirinAspirin (may improve aches, but could irritate

stomach)• Taking vitamin Bvitamin B66 before drinking may reduce the

severity of the hangover

Alcoholism and MalnutritionAlcoholism and Malnutrition

Alcohol-induced alterations in nutrient metabolism

(1) Interferes with activation of vitamins:» Vitamin D» Thaimine» Riboflavin» Folate » Vitamin B6» Increases degradation of B-complex vitamins

(2) Increases urinary excretion of nutrients:» B-vitamins» Zinc» Magnesium

(3) Decreases gluconeogenesis (due to excess NADH)

(4) Limits glycogen storage

(5) Suppresses fatty acid oxidation

(6) Increase in mobilization of stored fatty acids from adipocytes

Alcohol-induced alterations in nutrient metabolism

Does Alcohol Cause Weight Gain?Does Alcohol Cause Weight Gain?