Introduction
University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program
Ka wai hoʻomalule kino
The liquid that causes limpness to the body
Learning Objectives
By the end of this chapter, you will be able to:
- Describe the process of alcohol metabolism
- Describe the health benefits and health risks associated with alcohol consumption
is both a beverage providing some sustenance and a drug. For thousands of years, alcohol has been consumed in a medicinal, celebratory, and ritualistic manner. It is drunk in just about every country and often in excessive amounts. Alcohol can be made from a variety of different starch foods through the processes called fermentation. Fermentation of a starchy food such as barley or wheat can produce ethanol and CO2 which makes up what is commonly known as beer. The Native Hawaiians distilled a mash of fermented ti roots in iron try-pots pre-colonization in the 1700s. This form of alcohol was called “Okolehao”. This alcoholic beverage more commonly known today as “moonshine”, is still made locally in the islands today.[1]
Alcohol is a psychoactive drug. A psychoactive drug is any substance that crosses the blood-brain barrier primarily affecting the functioning of the brain, be it altering mood, thinking, memory, motor control, or behavior. Alcohols in chemistry refer to a group of similar organic compounds, but in beverages the only alcohol consumed is ethanol.
The Behavioral Risk Factor Surveillance System survey reported that more than half of the adult US population drank alcohol in the past thirty days.[2] Of the total population who drank alcohol, approximately 5 percent drank heavily, while 15 percent binge drank. (as defined by the National Institute on Alcohol Abuse and Alcoholism) is when men consume five or more drinks, and when women consume four or more drinks, in two hours or less.[3]
Alcohol in excess is detrimental to health; however since its beginnings it has been suspected and promoted as a benefit to the body and mind when consumed in moderation. In the United States, the Dietary Guidelines define moderate alcohol intake as no more than one drink per day for women and no more than two drinks per day for men.[4] Although drunkenness has pervaded many cultures, drinking in moderation has long been a mantra of multiple cultures with access to alcohol.
More than 90 percent of ingested alcohol is metabolized in the liver. The remaining amount stays in the blood and is eventually excreted through the breath (which is how Breathalyzers work), urine, saliva, and sweat. The blood alcohol concentration (BAC) is measured in milligrams percent, comparing units of alcohol to units of blood. BAC is a measurement used legally to assess intoxication and the impairment and ability to perform certain activities, as in driving a car. As a general rule, the liver can metabolize one standard drink (defined as 12 ounces of beer, 5 ounces of wine, or 1 ½ ounces of hard liquor) pe