Driving under the influence of alcohol (or any substance) is a serious crime. Not only that, it’s extremely dangerous to you and the people around you. Every day, roughly 29 people in the United States die as a direct result of involvement in an accident with an alcohol-impaired driver.
Alcohol consumption is a part of regular life for millions of Americans, however. It’s not just normal, but enjoyable to have a drink with friends on a regular basis, or several drinks as part of a fun night out. At some point, you may feel completely sober, but is it really okay to drive? Would you be able to defend against a DWI accusation? Would you be putting other people at risk?
Understanding the Legal Drinking Limit
First, you need to understand the limits in terms of national laws. In the United States, it’s illegal to drive if you have a blood alcohol concentration (BAC) of 0.05 or more. This is a measurement of how much alcohol is currently in your bloodstream. When you drink alcohol, it is introduced to your bloodstream, where it is gradually metabolized, eventually reducing its effects. That’s why you start to feel tipsy less than an hour after consuming your first alcoholic beverage, but it may take hours for the effects to fully wear off.
There are several variables that could influence how long the alcohol stays in your system and how many drinks it takes to get you drunk. For starters, the more you weigh, the lower your BAC will be, all other factors being equal. For example, after 2 standard drinks and 2 hours, a woman weighing 100 pounds would have a BAC of roughly 0.068, putting them over the legal limit, while a woman weighing 190 pounds would have a BAC of 0.021, putting them well under the legal limit. Men have a slightly different metabolism; a man weighing 190 pounds, after 2 drinks and 2 hours, would fall somewhere between a BAC of 0.016 and 0.012, putting them even further under the legal limit.
A “standard drink” in this case would be 12 fluid ounces of regular beer (at 5 percent alcohol content), 8 to 9 fluid ounces of malt liquor (at 7 percent alcohol content), 5 fluid ounces of wine (at 12 percent alcohol content), or 1.5 fluid ounces of distilled spirits like gin, rum, tequila, vodka, and whiskey.
Note that the legal limit, while important, doesn’t dictate when you’re 100 percent safe to drive. Driving under the legal limit may still be dangerous if your judgment and senses are impaired.
Other Variables to Consider
It’s also worth noting that several other variables can influence how alcohol affects you:
- Your metabolism. Different people naturally metabolize alcohol at different rates, even accounting for discrepancies due to age and sex. For example, 2 men each weighing 190 pounds may consume 2 drinks at the same time, but experience 2 very different levels of impairment 2 hours later.
- Your personal alcohol tolerance. Alcohol is a drug, and like any drug, the more you have it, the more of a tolerance you’ll develop. After drinking heavily and consistently for long enough, the effects of alcohol on your body and brain will be lessened.
- Time. As time passes, your BAC will lower and the effects of alcohol on your body will decrease. Therefore, the longer you wait between drinking and driving, the safer your decision will be.
After a few drinks and realizing you still need to drive home, you may be tempted to sober yourself up, improving your alertness and diminishing the effects of alcohol on your body. However, while there are many folk remedies for sobriety, the only true way to reduce the effects of alcohol is to give it time. Drinking coffee, exercising, and eating bread may make you feel more alert, but they won’t improve your impaired judgment, nor will they improve your reaction time.
Playing It Safe
It may also be in your best interest to stay as safe as possible, even if you feel like you’re okay to drive. Instead of crunching the numbers and figuring out exactly when you can leave and drive safely, give yourself a reasonable margin of error and avoid driving if you’ve had any drinks in the past several hours. Get yourself a designated driver, a taxi, a ridesharing service, or a cozy bed to sleep on; chances are, the people around you will be more than willing to help.
The Bottom Line
There are too many variables to determine when a person has had “too much” to drink, though as a general rule, you can count on waiting approximately an hour for every drink you’ve had to be sober enough to stay under the legal limit. Keep those variables in mind when drinking, always have a backup plan to get home (or stay the night), and if you’re even slightly in doubt about your ability to drive home safely, don’t drive.