Alcohol and Nutrition

Topic focuses on the relationship between alcohol consumption and nutrition from a biochemical perspective.

Structural formula of Ethanol: HIC
- Chemical composition: H—C—OH (Hydroxyl group attached to the carbon chain).
- Molecular structure includes a CH3 (methyl group) indicating it is a simple alcohol.

Moderation Levels:
  - Men: up to 2 drinks/day
  - Women: up to 1 drink/day
  - Pregnant Women:
    - Should abstain from alcohol consumption completely due to risk of impaired fetal development as ethanol crosses the placenta.

One standard drink equates to approximately 0.6 fluid ounces of pure ethanol.
Equivalent amounts are as follows:
  - Malt liquor: 8-10 fl. oz.
  - Flavored malt beverages & regular beer: 12 fl. oz.
  - Table wine: 5 fl. oz.
  - Fortified wine (e.g., Sherry, Port): 3-4 fl. oz.
  - Distilled spirits (e.g., gin, rum, whiskey): 1.5 fl. oz. per shot.
Alcoholic strengths represented:
  - Beer: ~5%
  - Flavored malt beverages: ~7%
  - Table wine: ~12%
  - Fortified wine: ~17%
  - Distilled spirits: ~40%

Absorption Characteristics:
- Alcohol does not require digestion; it is absorbed rapidly into the bloodstream.
- Absorption starts in the stomach, allowing alcohol to reach the brain in approximately 1 minute.
Factors Influencing Absorption:
- Empty Stomach: Higher absorption due to direct exposure of alcohol to stomach wall.
- Consumption of Fatty Foods: Fat slows down peristalsis, leading to increased absorption of alcohol in the stomach.

Primary Enzyme: Alcohol dehydrogenase (ADH) in the gastrointestinal tract metabolizes alcohol.
- Notably, women produce less ADH, leading to higher alcohol absorption.
Metabolic Hierarchy: Alcohol is prioritized over most nutrients for metabolism since it cannot be stored in the body.
Metabolic Pathways:
  - ADH: Alcohol dehydrogenase pathway.
  - MEOS: Microsomal ethanol-oxidizing system.
  - Catalase pathway.
Impact on Drug Metabolism:
- MEOS also metabolizes drugs and foreign substances, leading to decreased drug metabolism capacity when busy with alcohol.
Distribution: Alcohol is present in all body fluids wherever water is distributed, easily permeating cell membranes and potentially damaging membrane proteins.

Processing Capacity: The body can typically metabolize about 0.5 ounces of alcohol per hour, approximately the amount in one standard drink.
Liver Functions:
- Normally packages fatty acids into triglycerides; however, alcohol metabolism takes precedence.
Stages of Liver Deterioration:
  - Fatty Liver: Initial stage of liver damage.
  - Fibrosis: Second stage characterized by scarring of the liver.
  - Cirrhosis: Most advanced stage of liver deterioration, resulting in significant liver function impairment.

Visual differences between a healthy liver and one with cirrhosis:
- Healthy Liver: Normal appearance.
- Cirrhosis Symptoms: Jaundiced skin, visible fibrosis, and inflammation of liver tissue.

Caloric Contribution: Alcohol provides 7 kcal/g but lacks any supporting nutrients.
Physiological Effects:
- Ethanol suppresses antidiuretic hormone (ADH), leading to increased fluid losses and dehydration risk.
Nutritional Deficiencies Associated:
  - Alcohol abuse may disrupt nutritional status due to:
    - Reduced nutrient intake.
    - Impaired absorption and altered nutrient metabolism.
    - Alcohol-related tissue damage.
  - Key nutrient deficiencies linked to alcohol:
    - Thiamin: Associated with Wernicke-Korsakoff syndrome, impacting brain and nervous system.
    - Niacin: Vital for alcohol metabolism.
    - Vitamin B-6: Increased loss through urine.
    - Vitamin B-12: Impaired absorption.
    - Other vitamins and minerals affected: Riboflavin, Folate, Vitamin A, Vitamin D, Vitamin K, Calcium, Magnesium, Zinc, Iron.

Health Risks:
  - Heavy consumption factors into five of the ten leading causes of death, including:
    - Heart failure and arrhythmias.
    - Various cancers (oral cavity, pharynx, larynx, esophagus, liver, breast, colon, rectum).
    - Cirrhosis of the liver.
    - Accidental deaths (motor vehicle accidents, etc.).
    - Suicide.
Additional Health Concerns:
- Fluid retention in lungs, high blood pressure, risk of stroke, osteoporosis, brain damage, cognitive impairment, stomach inflammation, intestinal bleeding, pancreatitis, immune system suppression, sleep disturbances, impotence, glucose irregularities (hypo- or hyperglycemia), abdominal obesity, elevated triglycerides, and nutrient deficiencies.

Ongoing research assesses the pros and cons of moderate alcohol intake, indicating that increased risks correlate with higher consumption levels.

When to Avoid Alcohol:
  - If unable to limit consumption to moderate levels.
  - During pregnancy.
  - If under legal drinking age.
  - While taking medications that interact negatively with alcohol.
  - In the presence of specific medical conditions.
  - When engaging in activities requiring attention, skill, or coordination.

Approximate BAC Levels:
- Blood alcohol percentages depend on the number of drinks consumed, body weight, and sex.
Effectiveness on Motor Skills at Various Levels:
  - .05: Legally safe limit; skills may be affected.
  - .08: Legally intoxicated; significant skill impairment.
  - Higher levels (up to .40 and beyond) indicate severe impairment or risk of death due to alcohol intoxication.