A single shot of tequila, typically 1.5 ounces of 80-proof spirit, contains 0.6 ounces of pure alcohol, defining one standard drink. The body’s systems are highly sensitive to this rapid introduction of ethanol, and even this small quantity causes a measurable effect. Understanding the outcome of this single serving depends on how quickly the alcohol is absorbed and the variables that influence this process.
The Swift Chemistry of Alcohol Absorption
Alcohol (ethanol) does not require digestion, allowing it to bypass normal metabolic processes in the stomach. A small portion is absorbed immediately through the stomach lining, but the majority passes swiftly into the small intestine. The small intestine’s large surface area and rich blood supply facilitate the rapid transfer of alcohol directly into the bloodstream, where it circulates throughout the body, including the brain.
The concentration of alcohol in the blood, known as the Blood Alcohol Concentration (BAC), is the measurable metric of intoxication. Because tequila is a concentrated spirit, it is absorbed faster than beverages with lower alcohol content, such as beer or wine. An average person consuming a single shot on an empty stomach can reach peak BAC within 30 to 90 minutes. This rapid spike in BAC, even at a low level, triggers the noticeable initial sensations.
Personal Variables That Determine the Outcome
The intensity of the effects from a single shot varies greatly between individuals due to biological and environmental factors. Total body mass is significant because alcohol is diluted by the body’s water content. Individuals with greater muscle mass and higher body weight have a larger volume of water for dilution, resulting in a lower peak BAC compared to smaller individuals. This dilution effect means the same shot of tequila will produce a different concentration of alcohol for two people of differing sizes.
The presence of food in the stomach is another major modifier of the absorption rate and peak effect. When alcohol is consumed alongside a meal, especially one rich in protein, the food delays the movement of the alcohol from the stomach into the small intestine. This slower passage significantly slows the absorption rate, lowering the peak BAC reached and lengthening the time it takes to achieve that peak. Drinking a shot on an empty stomach allows for maximum absorption speed and a higher concentration spike.
Differences based on biological sex also influence the outcome. On average, females tend to have a lower percentage of body water and lower levels of the stomach enzyme alcohol dehydrogenase (ADH) than males. Since ADH begins the process of breaking down alcohol before it enters the bloodstream, lower enzyme activity and less water for dilution mean females generally achieve a higher BAC than males of the same weight consuming the same shot. Furthermore, an individual’s habituation to alcohol, often termed tolerance, means regular drinkers may require a higher concentration to feel the same effects.
Immediate Mental and Physical Alterations
A single standard shot places most people in a very low BAC range, typically between 0.01% and 0.03%. At this minimal level, the observable changes are subtle and short-lived, but they are genuine alterations to the central nervous system. Subjectively, a person may experience a slight feeling of warmth or a minor flush as blood vessels dilate. This is often accompanied by mild euphoria and relaxation.
This low level of alcohol also begins to affect cognitive function. Individuals may feel slightly less inhibited or more sociable. Objectively, minor impairment in judgment and coordination begins at this stage, though it is usually not overtly noticeable to the person consuming the drink. Physical effects are minimal, perhaps manifesting as a slight reduction in reaction time or minor sensory changes.
Metabolism and Return to Baseline
Once the alcohol has been absorbed and the BAC has peaked, the body’s clearance process takes over to return the system to baseline. The liver is primarily responsible for this process, relying on the alcohol dehydrogenase enzyme to break down ethanol into acetaldehyde and then harmless acetic acid. This metabolic process occurs at a fixed rate that cannot be accelerated by external factors like coffee or cold showers.
The liver can metabolize approximately one standard drink (the amount of alcohol in one shot of tequila) per hour. The average body clears alcohol at a rate that reduces the BAC by about 0.015% to 0.016% per hour. Since one shot is one standard drink, it generally takes around one hour for the body to process that single serving completely after full absorption. This fixed clearance rate ensures the effects of the shot are temporary, leading to a predictable return to a zero BAC.