Lots of things can affect blood alcohol levels, so if you're planning on drinking and driving, you can't rely on generalisations that tell you you can have two glasses of wine or a pint of beer and still pass a breath test if you're unlucky enough to get stopped.
Raised blood alcohol levels may also interfere with any medication you're taking, or make an existing health condition - such as a fatty liver or cirrhosis - much worse. These are just some of the factors that could affect your blood alcohol levels.
Ladies have a higher fat to water ratio in the body. This means there's less water to dilute the strength of the alcohol, so if husband and wife have the same drinks in the same quantities, her blood alcohol level will be higher than his. And as men tend to be more muscular than women, the alcohol is processed more quickly. Ladies can even this out a little by taking more exercise to build muscle mass. No, itsn't fair, but it's the way it is.
The larger you are, the more water is in your body to lessen the strength of the booze. As women are generally smaller than men, it's a double whammy for the girls, unfortunately.
The presence of food in the stomach slows the rate of absorption of alcohol. That's why articles on avoiding hangovers suggest you eat before you start to drink. Drinking on an empty stomach is the quickest route to inebriation.
The speed of the elbow bending
If you drink a bottle of wine over the course of an evening, you may feel pleasantly warm and fuzzy or a bit drunk, depending on your alcohol tolerance levels. However, if you demolish that same bottle of wine in an hour or so, your blood alcohol level will be much higher, as you're drinking faster than your body can process the alcohol.
Time and metabolism
The body processes around one unit of alcohol per hour, so as time passes, your blood alcohol level decreases. If you've had a heavy night's drinking, you may still be over the legal limit for blood alcohol next morning, and the condition of your liver affects the rate of processing. A diseased liver will take longer to remove alcohol from the body, as it's less active.
Like most things in life, alcohol is fine in moderation. It's when you overdo it that it can impact on your health and your lifestyle. Understanding the factors that influence blood alcohol levels can help you towards responsible alcohol consumption. Enjoy a drink or two, but be careful out there.