Which factors influence a person’s BAC?

• A. Body weight, metabolism, and rate of alcohol consumption (plus food in stomach and gender).
• B. Eye color, height, and favorite cuisine.
• C. Mood, preferred music, and temperature.
• D. Time of day, day of week, and weather.

Answer: (A)

When a person’s blood alcohol concentration (BAC) is affected, it’s about how alcohol is absorbed, distributed, and cleared by the body. The most important factors are body weight, metabolism, how quickly alcohol is consumed, whether there’s food in the stomach, and gender.

Body weight influences BAC because more body water tends to dilute the alcohol, so heavier individuals often reach a lower BAC than lighter individuals after drinking the same amount. Metabolism matters because the liver breaks down alcohol at a relatively constant rate, so faster metabolism lowers BAC more quickly. The rate of consumption matters because drinking quickly can overwhelm the body’s ability to metabolize alcohol, causing higher peaks in BAC. Food in the stomach slows the absorption of alcohol into the bloodstream, leading to a lower and slower rise in BAC. Gender also plays a role due to differences in body composition and enzyme activity, which can affect how alcohol is absorbed and cleared.

The option that lists body weight, metabolism, and rate of alcohol consumption, plus food in the stomach and gender, captures these physiological and metabolic factors, making it the best choice. The other options include traits like eye color, height, mood, or weather, which do not directly influence how alcohol appears in the blood, so they’re not correct.