Hey Doc: A friend of mine recently got pulled over for a DUI. He weighs a good 210 pounds and only had four beers at our company picnic, but he still got pulled over and arrested. Now his license is suspended for six months, he’s paying a stiff fine, and it impacted his annual review. I want to make sure that never happens to me! What’s your advice? -- Senior Airman Brandy 

Dear Senior Airman Brandy: I'm sorry to hear about your friend. Sounds like you're looking for information about alcohol's effects on your body over time, the factors behind the impact of alcohol, and the how it affects your ability to operate a vehicle. I've reached out to an expert to answer your questions: Dr. John Shehan, a psychiatrist and head of the Addiction Medicine Intensive Outpatient Program at the Carl R. Army Medical Center at Fort Hood in Texas.

Here's what Dr. Shehan had to say.

How alcohol impacts your body is first and foremost a function of time. On average, you metabolize about a drink an hour. So, if you drink four drinks in under an hour, it's probably going to take a good four hours for you to process that alcohol out of your system.

There is little difference in the rate of alcohol absorption between different types of alcoholic beverages. Different types of alcohol have what is called “alcohol by volume,” or ABV, and this means the amount of pure ethanol (alcohol) in a given volume of beverage.

The higher the ABV, the lower the number of ounces you can drink that qualify as one standard drink.

For instance, a 12-ounce beer is equivalent to one standard drink. Beer typically has 5% ABV. A standard drink of malt liquor is about 7% ABV, but that's only 8 ounces. A standard drink of wine is 12% ABV and is only 5 ounces, while a 1.5-ounce whiskey is 40% ABV. All those are equivalent to one drink.

Factors for the Impact of Alcohol

There are other factors involved in how you respond to alcohol, such as your tolerance and your gender. Different people process alcohol differently.

How you react to alcohol depends on how much water content you have in your body, your rate of blood flow, and also the kind of tissue mass you have. In fact, alcohol doesn't disperse easily, but in water it can pass through your body more effortlessly.

Women are going to have a higher blood alcohol level concentration when they drink the same dose of alcohol per body weight. That's because typically they have less of the enzyme in their stomach that helps to metabolize alcohol. And they also have higher total body fat relative to water concentration in their bodies.

If you eat before you drink, it can slow down the absorption of alcohol, but the alcohol still needs to be broken down in your body. People who drink on an empty stomach will get drunk faster. Food only delays the rate of alcohol getting absorbed into your system.

Your body will still get the same amount of alcohol but just in a delayed fashion. This could encourage people to drink more because they don't feel that drunk, which could be dangerous. A meal will not protect you from becoming intoxicated. Also, drinking caffeine has no effect on how your body metabolizes alcohol. It might make you feel more alert, but then you might drink more alcohol and become more intoxicated.

Drinking, Driving, and Duty

Impaired driving due to alcohol use begins to occur at limits well below the legal limit of 0.08%, and 0.04% is drunk on duty.

Alcohol use slows reaction time and impairs judgment, which are all skills you need to drive a vehicle safely or perform your daily duties.

If you have three or four drinks an hour, you'll be well above most states' legal limit. If you get behind the wheel of a car, truck or motorcycle, you could get a DWI or DUI, like your friend did, or you could get into a serious accident or even injure or kill someone.

DUI's can be very expensive. Generally, they will cost you about $10,000 in legal fees. If you get a DUI, you also may face the loss of your military benefits and pension or even receive a dishonorable discharge.

The bottom line is that drinking and driving don't make sense. Be smart and limit your drinking to no more than two drinks in a sitting for men and no more than one drink in a sitting for women.

There is never a good time to drink and drive, and I strongly discourage even modest amounts of alcohol and driving. But, if you do drink, take a licensed car service or a taxi home or use a designated driver.

Senior Airman Brandy, I hope this answers your questions about drinking and can help you understand alcohol's effects over time so you don't put yourself or others in danger, or worse. For more information, check out the> Alcohol's  Effects on Your Body page at the National Institute for Alcohol Abuse and Prevention or the Centers for Disease Control and Prevention page on impaired driving Good luck, my friend, and as always, take care of each other out there!