ELI5: Why does blood alcohol percentage not seem to mathematically jive with the amount of alcohol consumed?

r/

Okay, so if a human body contains five liters of blood and a standard shot is (let us be generous for ease of calculation) 50 mL (google says 44) and half of that (100 proof) is alcohol…

Why do people get hardcore DUI drunk off of three shots when 75/5075 isn’t 0.08%?

Comments

  1. HearthGaleXO Avatar

    because alcohol doesn’t just stay in your blood like food coloring in water, it gets absorbed into your whole body, including tissues and organs. plus, your liver is constantly processing it, so the concentration in your blood isn’t just a simple volume equation. also, BAC is measured by weight, not volume, which makes the math even trickier

  2. LindaTheLynnDog Avatar

    75/5075 = 1.4%

    I don’t know anything else about this question, but I believe you forgot that 1% in decimal form is .01

  3. TorakMcLaren Avatar

    Well, 75/5075=0.014, which is about 1.4%. I’m wondering if you forgot to convert from decimal to percent?

    But the alcohol won’t all immediately be in the blood. It needs to get into the blood, which takes a little time, so it’ll be a bit less than 1.4%.

    Just as an aside, in the UK (can’t speak for other countries) the standard size for a measure of a spirit is either 25ml or 35ml. (The venue can choose which standard they go by.) Liqueurs are often served at 50ml.

  4. phiwong Avatar

    0.08% = 0.08/100 = 8/10000

    75/5075 = 150/10150 which is approx 150/10000 which is far far more than 8/10000

    So 75mL of pure alcohol in your bloodstream would make a person blind drunk or possibly pass out.