Diabetes and Alcohol

Alcohol is everywhere - when the family gathers, at cookouts, after the softball game, at parties. "What will you have?" someone asks. If you have diabetes, what do you say?

It all depends. Start by asking yourself three basic questions:

  1. Is my diabetes under control?
  2. Does my health care provider agree that I am free from health problems that alcohol can make worse-for example, diabetic nerve damage or high blood pressure?
  3. Do I know how alcohol can affect me and my diabetes?

If you said "yes" to all three, it's OK to have an occasional drink. But what does occasional mean? The American Diabetes Association suggests that you have no more than two drinks a day if you are a man and no more than one drink a day if you are a woman. This recommendation is the same for people without diabetes.

Your Body and Alcohol

Alcohol moves very quickly into the blood without being broken down (metabolized) in your stomach. Within five minutes of having a drink, there's enough alcohol in your blood to measure. Thirty to 90 minutes after having a drink, the alcohol in your bloodstream is at its highest level.

Your liver does most of the job of breaking down the alcohol once it's in your body. But it needs time. If you weigh 150 pounds, it will take about 2 hours to metabolize a beer or mixed drink.

If you drink alcohol faster than your liver can break it down, the excess alcohol moves through your bloodstream to other parts of your body. Brain cells are easy targets. When someone talks about getting a buzz from alcohol, this is what they are feeling.

Risk of Low Blood Sugar

If you have diabetes and take insulin shots or oral diabetes pills, you risk low blood sugar when you drink alcohol. To protect yourself, never drink on an empty stomach. Plan to have your drink with a meal or after eating a snack.

How does alcohol add to your chances of having low blood sugar? It has to do with your liver.

Normally, when your blood sugar level starts to drop, your liver steps in. It goes to work changing stored carbohydrate into glucose. Then it sends the glucose out into the blood, which helps you avoid or slow down a low blood sugar reaction.

However, when alcohol enters your system, this changes. Alcohol is a toxin. Your body reacts to alcohol like a poison. The liver wants to clear it from the blood quickly. In fact, the liver won't put out glucose again until it has taken care of the alcohol. If your blood glucose level is falling, you can quickly wind up with very low blood sugar.

This is why drinking as little as 2 ounces of alcohol (about 2 drinks) on an empty stomach can lead to very low blood sugar.

When you mix alcohol and exercise, you increase the risk of going low. This can happen because exercise helps lower your blood sugar levels. Let's say you just played a couple of hard sets of tennis. You have a beer after the match. But in the hours after the game, your body is still working. It is replacing the energy your muscles used up. To do this, it clears glucose from the blood and adds it to the muscles' store. This is why exercise can cause your blood sugar level to go down.

If you take insulin or diabetes pills, they too are working to clear glucose from your blood. Unless you eat or your liver adds glucose to your blood, you could be heading for a low blood sugar level. If you drink a beer, the alcohol will stop your liver from sending out any glucose. Your chances of going low are even greater.

Check with your health care provider to see if it's OK to combine alcohol with your diabetes medications. 

Low blood sugar when drinking is less of a risk for those with type 2 diabetes who control their diabetes with meal planning and exercise alone.

Don't Go Low

Follow these guidelines to avoid low blood sugar levels when you drink:

  • Never drink alcohol on an empty stomach.
  • Limit yourself  to 1 drink if you're a woman or 2 drinks if you are a man.

Alcohol affects your body's ability to get over a low blood sugar level. If you have low blood sugar, you may need to treat it more than once as time goes by. If you've been drinking, check your blood sugar before you go to sleep. Eat a snack before you retire to avoid a low blood sugar reaction while you sleep.

A warning: glucagon shots don't help severe low blood glucose caused by drinking. Glucagon shots treat very severe low blood glucose reactions caused by too much insulin. Glucagon works by getting your liver to release more glucose into your blood. But alcohol stops this process. You need to be able to treat your reaction with a carbohydrate, such as oral glucose tablets or gels. So you need to avoid letting a low blood glucose level become severe. If you pass out, you will need glucose injected into your bloodstream by a health care professional.

Heavy drinking over time can hurt your liver. It won't be able to make glucose as well. When this happens, your diabetes is harder to control. 

Some of the signs of drinking too much, such as confusion or slurred speech, are similar to the effects of a low blood sugar reaction or ketoacidosis (most common in people with type 1 diabetes who have taken too little insulin). You may be asked to take a blood or a breath test for alcohol if you have some of these signs. Don't worry. Diabetes will not affect the results of a test for alcohol, even if you are having a reaction or have a fruity smell to your breath because of high ketone levels. If you are asked to take a test for alcohol and you have a choice, choose a blood test. That way, health care providers can check your levels of glucose and ketones, too.

Beer Belly Blues

Although an occasional drink may not hurt your blood sugar control, it can harm your eating plan if your goal is weight loss. Two light beers equal about 200 extra calories. Alcohol is called empty calories because it does not give you any nutrients.

If you are on a low-calorie meal plan, think twice about adding alcohol. In general, alcohol counts as fat servings (1 drink equals 2 fat exchanges).

Wise Drink Choices

Some drinks are better choices for people with diabetes. Select drinks that are lower in alcohol and sugar. If you use mixers in your drinks, choose ones that are sugar free, such as diet soft drinks, diet tonic, club soda, seltzer, or water. This will help keep your blood sugar levels in your target range.

Light beer and dry wines are good choices. They have less alcohol and carbohydrates and fewer calories.

To make drinks last longer, try a "spritzer." Mix wine with sparkling water, club soda, or diet soda. Try a "virgin" Bloody Mary made without alcohol.

When Alcohol Is a Poor Choice

Some people with diabetes should not drink alcohol. Alcohol can make some diabetic problems worse.

If you have nerve damage from diabetes in your arms or legs, drinking can make it worse. Alcohol is toxic to nerves. Drinking can increase the pain, burning, tingling, numbness, and other symptoms found with nerve damage. Some studies show that even regular light drinking (less than two drinks per week) can bring on nerve damage.

Heavy drinking (3 or more drinks per day) may make diabetic eye disease worse. If you have high blood pressure, you can lower it if you stop drinking alcohol.

Many people with diabetes have high levels of the fat called triglyceride in their blood. If you do, you should not drink alcohol. Alcohol affects how the liver clears fat from the blood. Alcohol also spurs the liver on to make more triglycerides. Even light drinking (two 4-ounce glasses of wine a week) can raise triglyceride levels.

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What is Alcohol?
In order to understand alcohol's effects on the body, it is helpful to understand the nature of alcohol as a chemical, so let's take a look...

Here are several facts:

  • Alcohol is a clear liquid at room temperature.
  • Alcohol is less dense and evaporates at a lower temperature than water (this property allows it to be distilled -- by heating a water and alcohol mixture, the alcohol evaporates first).
  • Alcohol dissolves easily in water.
  • Alcohol is flammable (so flammable that it can be used as a fuel).

Alcohol can be made by four different methods:

  • Fermentation of fruit or grain mixtures (See How Beer Works for details.)
  • Distillation of fermented fruit or grain mixtures (Spirits such as whiskey, rum, vodka and gin are distilled.)
  • Chemical modification of fossil fuels such as oil, natural gas or coal (industrial alcohol)
  • Chemical combination of hydrogen with carbon monoxide (methanol or wood alcohol)

Ethyl Alcohol
The alcohol found in alcoholic beverages is ethyl alcohol (ethanol). The molecular structure of ethanol looks like this:

3 C - C - O - H

In this structure, C is carbon, H is hydrogen, O is oxygen and the hyphens are the chemical bonds between the atoms. For purposes of clarity, the bonds between the three hydrogen atoms and the left carbon atom are not shown. The OH (O-H) group on the molecule is what gives it the specific chemical properties of an alcohol. For the remainder of this article, when we say "alcohol," we mean ethanol.

You will not find pure alcohol in most drinks; drinking pure alcohol can be deadly because it only takes a few ounces of pure alcohol to quickly raise the blood alcohol level into the danger zone. For various types of beverages, the ethanol concentration (by volume) is as follows:

  • Beer = 4 to 6 percent (average of about 4.5 percent)
  • Wine = 7 to 15 percent (average of about 11 percent)
  • Champagne = 8 to 14 percent (average of about 12 percent)
  • Distilled spirits (e.g. rum, gin, vodka, whiskey) = 40 to 95 percent
    • Most of the typical spirits purchased in liquor stores are 40 percent alcohol.
    • Some highly concentrated forms of rum and whisky (75 to 90 percent) can be purchased in liquor stores.
    • Some highly concentrated forms of whiskey (i.e. moonshine) can be made and/or purchased illegally.

In most U.S. states, you must be 21 years or older to buy alcoholic beverages, and there are penalties for serving or selling alcoholic beverages to minors.


How Alcohol Enters the Body

Alcohol Effects:
Men vs. Women

When you compare men and women of the same height, weight and build, men tend to have more muscle and less fat than women. Because muscle tissue has more water than fat tissue, a given dose or amount of alcohol will be diluted more in a man than in a woman. Therefore, the blood alcohol concentration resulting from that dose will be higher in a woman than in a man, and the woman will feel the effects of that dose of alcohol sooner than the man will.

When a person drinks an alcoholic beverage, about 20 percent of the alcohol is absorbed in the stomach and about 80 percent is absorbed in the small intestine. How fast the alcohol is absorbed depends upon several things:

  • The concentration of alcohol in the beverage - The greater the concentration, the faster the absorption.
  • The type of drink - Carbonated beverages tend to speed up the absorption of alcohol.
  • Whether the stomach is full or empty - Food slows down alcohol absorption.

After absorption, the alcohol enters the bloodstream and dissolves in the water of the blood. The blood carries the alcohol throughout the body. The alcohol from the blood then enters and dissolves in the water inside each tissue of the body (except fat tissue, as alcohol cannot dissolve in fat). Once inside the tissues, alcohol exerts its effects on the body. The observed effects depend directly on the blood alcohol concentration (BAC), which is related to the amount of alcohol consumed. The BAC can rise significantly within 20 minutes after having a drink.


How Alcohol Leaves the Body
Once absorbed by the bloodstream, the alcohol leaves the body in three ways:

  • The kidney eliminates 5 percent of alcohol in the urine.
  • The lungs exhale 5 percent of alcohol, which can be detected by breathalyzer devices.
  • The liver chemically breaks down the remaining alcohol into acetic acid.

As a rule of thumb, an average person can eliminate 0.5 oz (15 ml) of alcohol per hour. So, it would take approximately one hour to eliminate the alcohol from a 12 oz (355 ml) can of beer.

The Breakdown of Alcohol

The breakdown, or oxidation, of ethanol occurs in the liver. An enzyme in the liver called alcohol dehydrogenase strips electrons from ethanol to form acetaldehyde. Another enzyme, called aldehyde dehydrogenase, converts the acetaldehyde, in the presence of oxygen, to acetic acid, the main component in vinegar. The molecular structure of acetic acid looks like this:

H3 C - C - O - H

The || symbol is a double bond between the atoms. When ethanol is oxidized to acetic acid, two protons and two electrons are also produced. The acetic acid can be used to form fatty acids or can be further broken down into carbon dioxide and water.

The BAC increases when the body absorbs alcohol faster than it can eliminate it. So, because the body can only eliminate about one dose of alcohol per hour, drinking several drinks in an hour will increase your BAC much more than having one drink over a period of an hour or more.

The Effects of Alcohol

If you have seen someone who has had too much to drink, you've probably noticed definite changes in that person's performance and behavior. The body responds to alcohol in stages, which correspond to an increase in BAC:

  1. Euphoria (BAC = 0.03 to 0.12 percent)
    • They become more self-confident or daring.
    • Their attention span shortens.
    • They may look flushed.
    • Their judgement is not as good -- they may say the first thought that comes to mind, rather than an appropriate comment for the given situation.
    • They have trouble with fine movements, such as writing or signing their name.
  2. Excitement (BAC = 0.09 to 0.25 percent)
    • They become sleepy.
    • They have trouble understanding or remembering things (even recent events).
    • They do not react to situations as quickly (if they spill a drink they may just stare at it).
    • Their body movements are uncoordinated.
    • They begin to lose their balance easily.
    • Their vision becomes blurry.
    • They may have trouble sensing things (hearing, tasting, feeling, etc.).
  3. Confusion (BAC = 0.18 to 0.30 percent)
    • They are confused -- might not know where they are or what they are doing.
    • They are dizzy and may stagger.
    • They may be highly emotional -- aggressive, withdrawn or overly affectionate.
    • They cannot see clearly.
    • They are sleepy.
    • They have slurred speech.
    • They have uncoordinated movements (trouble catching an object thrown to them).
    • They may not feel pain as readily as a sober person.
  4. Stupor (BAC = 0.25 to 0.4 percent)
    • They can barely move at all.
    • They cannot respond to stimuli.
    • They cannot stand or walk.
    • They may vomit.
    • They may lapse in and out of consciousness.
  5. Coma (BAC = 0.35 to 0.50 percent)
    • They are unconscious.
    • Their reflexes are depressed (i.e. their pupils do not respond appropriately to changes in light).
    • They feel cool (lower-than-normal body temperature).
    • Their breathing is slower and more shallow.
    • Their heart rate may slow.
    • They may die.
  6. Death (BAC more than 0.50 percent) - The person usually stops breathing and dies.

How the Body Responds to Alcohol
Alcohol acts primarily on the nerve cells within the brain. Alcohol interferes with communication between nerve cells and all other cells, suppressing the activities of excitatory nerve pathways and increasing the activities of inhibitory nerve pathways.

How Nerve Cells Talk

Nerve cells talk to each other and to other cells (such as muscle or gland cells) by sending chemical messages. These messages are called neurotransmitters.

An electrical signal travels down one nerve cell, causing it to release the neurotransmitter into a small gap between cells called the synapse. The neurotransmitter travels across the gap, binds to a protein on the receiving cell membrane called a receptor, and causes a change (electrical, chemical or mechanical) in the receiving cell. The neurotransmitter and receptor are specific to each other, like a lock and key. Neurotransmitters can either excite the receiving cell to cause a response or inhibit the receiving cell from stimulation.

For example, University of Chicago Medical Center: Alcohol and Anesthetic Actions talks about the ability of alcohol (and inhaled anesthetics) to enhance the effects of the neurotransmitter GABA, which is an inhibitory neurotransmitter. Enhancing an inhibitor would have the effect of making things sluggish, which matches the behavior you see in a drunk person. Glutamine is an excitatory neurotransmitter that alcohol weakens. By making this excitatory neurotransmitter less effective, you also get sluggishness. Alcohol does this by interacting with the receptors on the receiving cells in these pathways.

Alcohol affects various centers in the brain, both higher and lower order. The centers are not equally affected by the same BAC -- the higher-order centers are more sensitive than the lower-order centers. As the BAC increases, more and more centers of the brain are affected.

The order in which alcohol affects the various brain centers is as follows:

  1. Cerebral cortex
  2. Limbic system
  3. Cerebellum
  4. Hypothalamus and pituitary gland
  5. Medulla (brain stem)

Source : www.howstuffworks.com


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Last updated on 06/07/2008