The Standard Drink is a simple tool you can use to protect your health. It helps you measure your alcohol consumption. Doctors and medical researchers agree, and we all know, that drinking too much alcohol has negative health consequences. Whether the excess comes in the form of binge drinking or an extended period of less dramatic but still excessive consumption, too much alcohol takes a toll on you. Excessive drinking is known to increase the risk of some types of cancer, disease of the heart, liver, pancreas, brain, other organs, and more.

Yet we are often told that moderate alcohol consumption, especially red wine, may offer health benefits. Moderate is a fuzzy word. What does it mean? If we don’t get drunk are we being moderate? Is one-glass of wine a day moderate? How about three glasses? If we want to drink moderately for our health or just for pleasure, where do we draw the line?

Fortunately, physicians and various national governments have created a measure of alcohol called the Standard Drink. They then define moderate, or low-risk, alcohol consumption in terms of the number of Standard Drinks allowed per week. These guidelines are very helpful, but you need to know what a Standard Drink is in order to put them into practice.

A Standard Drink is a specific quantity of pure alcohol. This quantity varies from country to country. The U.S. government declares it to be 0.6 fluid ounces of pure alcohol. That’s equivalent to one 5 oz. glass of 12% alcohol wine,  or a 1.5 oz. shot of 80 proof liquor or 12 oz. of 5% alcohol beer.

The general guidelines in the United States for maximum Standard Drink consumption are 14 per week for men, 9 for women and not more than 2 per day for anyone. Specific recommendations on how many Standard Drinks an individual ought to limit themselves to depends on that person’s individual health situation, family medical history, etc. For example, women at increased risk for breast cancer should drink even less and those who are either pregnant or nursing should not drink alcohol at all. There are conditions that decrease the number for men too. And use of certain medications also calls for decreased consumption. Your doctor can help you find the right number.

As a wine enthusiast, you will have noted that the Standard Drink for wine mentioned above assumes an alcohol percentage of 12%. And you probably either laughed or choked. The reality is that few wines today have alcohol levels as low as 12%. There are a few varietals that tend to be in that range: Riesling, Sauvignon Blanc, Gamay. Most do not. New World wines and those from grape-growing regions with warm weather can be substantially higher. I tasted a Zinfandel the other day that had a listed alcohol percentage of 17.8%. If your wine is more than 12% alcohol, you need to reduce the volume of the Standard Drink from 5 oz to something smaller.

This calculation is easy to perform. A wine’s stated alcohol percentage tells you exactly how much pure alcohol will be in 1 oz. Just express the percentage in terms of a decimal number. For example, a 15% alcohol wine will contain 0.15 oz of pure alcohol for each ounce of wine. And you now know that a Standard Drink is 0.6 oz of pure alcohol. To get the amount of 15% alcohol wine in a Standard Drink, simply divide 0.6 by 0.15. The result is 4 and that is the number of ounces in a Standard Drink of that wine. A 750ml bottle (the most common size of wine bottle) holds just over 25 ounces. So, there would be a little bit more than 6 Standard Drinks in such a bottle if the wine is 15% alcohol. Splitting that bottle between two people in one evening would exceed the recommended limit for consumption in a single day.

What about that 17.8% Zinfandel? Well, the Standard Drink volume for that wine is just 3.37 ounces. That’s about the amount most bars and restaurants call a half-glass and others call a taste. According to the U.S. guidelines, if you have a full glass of that wine (most restaurants pour at least 6 ounces per glass), you’re done for the day.

One thing to bear in mind if you travel, or are just thinking that a Standard Drink sounds small, is that the U.S. Standard Drink is one of the most generous in the world. Our measure is equal to that of Portugal and smaller than those in Hungary and Japan. However, most other countries suggest lower alcohol consumption – many dramatically lower. Austrian guidelines use a Standard Drink with just 0.25 ounces of pure alcohol. They would literally prefer wine bars to serve that Zinfandel in a shot glass.

One of the reasons Standard Drink sizes vary is that governments also hope consumers will use them as a guide to avoid drunk driving. While different people absorb and metabolize alcohol at different rates, a general rule of thumb is that you can consume one Standard Drink per hour, with food, and remain under the legal blood alcohol limits for driving. The Austrians also suggest that keeping consumption down to four Standard Drinks (that would be two American Standard Drinks) or less on any one occasion also reduces the risk of physical injury due to other types of accidents and violence. Getting “falling down drunk” can have nasty consequences.

To recap:
A U.S. Standard Drink is 0.6 oz. of pure alcohol
Divide 0.6 by your wine’s alcohol percentage (ex. 0.145) to get the volume of a Standard Drink for that wine.

U.S. recommendations are no more than 2 Standard Drinks per day with a maximum of 14 per week for men and 9 for women.
Consult with your doctor to find out what is appropriate for you.

To reduce the risk of driving while impaired, limit your consumption to 1 Standard Drink per hour and make sure you have food with it.
If you anticipate drinking more than that, call a taxi or use a designated driver.

This article is original to NorCalWine.com. Copyright 2010 NorCal Wine. All rights reserved.

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