One unit of alcohol is roughly the equivalent of half a beer or most of a small glass of wine. This is the main measurement used for alcohol consumption, and usefully makes it easy to calculate roughly how much alcohol is in your blood at any time. As a general rule, one unit of alcohol takes one hour to leave the blood and two units take two hours etc. However this number will vary dependent on several factors.
For example your weight can affect how long alcohol takes to leave your system, with the heavier individual generally sobering up more quickly as units of alcohol make up a smaller percentage of their body mass. Meanwhile though, thin people are likely to have a faster metabolism which would contribute to the alcohol leaving the system quicker. Meanwhile your gender too can affect the amount of time alcohol stays in the blood with males generally being faster to get rid of it. Age too can play a role on your sobriety with those between the ages of 20-30 being the quickest to get the alcohol out of their blood stream.
Interestingly, even stress and psychological factors can play a role in how long your blood retains alcohol. This is just one of the surprising examples of the mind and body link in action. The amount of food you have eaten can also help your body to dispel alcohol as it increases your metabolism and allows other nutrients to enter your blood stream and line your stomach (which is where the alcohol passes into your blood). Similarly water can also help you to sober up more quickly – thinning and diluting the alcohol in your blood while at the same time forcing your body to flush itself out more and expel toxins through urine. Be aware that medication can also play a role in your sobriety and in some cases cause unwanted reactions. Finally, if you have liver problems (which ironically are often caused by alcohol) then this can cause your body to take longer to get rid of the alcohol in the blood.
These facts can all be useful in helping yourself to become more sober more quickly, and to understand your own and other people’s limits better. Eating, drinking water or getting fresh air can all help you to sober up more quickly, and you can assess your limit and that of others by their age, gender and weight. A useful tip for if you want to sober up without being a party-pooper, is that if you drink very slowly (under half a pint an hour) and drink lots of water, then you can actually sober up slowly *while* drinking.
this site did not answer my question, but did offer good information…