What factors can affect individual responses to alcohol?

Many Australians enjoy a drink. In fact, alcohol is Australia’s most widely used social drug. Like all drugs, alcohol can damage your body, especially if you drink heavily every day or in binges. Even small amounts of alcohol are still linked to the development of certain diseases, including numerous cancers.

Alcohol affects your body in many ways. Some effects are immediate and last only a while; others accumulate over time and may significantly affect your physical and mental health and quality of life.

How much harm alcohol causes your body depends on how much you drink, your pattern of drinking, and even the quality of the alcohol you drink. Your body size and composition, age, drinking experience, genetics, nutritional status, metabolism, and social factors all play a part as well.

The short-term effects of alcohol

The short-term effects of a single occasion of drinking too much alcohol can include:

• lowered inhibitions
• interpersonal conflict
• falls and accidents
• altered behaviour – including risky or violent behaviour
• hangover
• alcohol poisoning.

The severity of the short-term effects of alcohol typically depends on how much a person drinks, but other factors such as hydration and food consumption also play a role.

Hangover

You’ve probably heard of, or perhaps experienced, a ‘hangover’ – a set of unpleasant symptoms that usually follows excessive alcohol intake. Most people can recognise the signs and treat the symptoms themselves.

Generally, the more you drink the higher the likelihood you’ll experience a hangover, but there’s no way to predict how much you may be able to drink and avoid a hangover. Some people can experience a hangover from one drink.

The severity of a hangover often has to do with how your body metabolises alcohol, as when you drink, alcohol triggers a number of reactions in your body. These reactions can contribute to hangover. They include:

• frequent urination and dehydration
• an inflammatory response from your immune system
• irritation of the stomach lining
• a drop in blood sugar
• an expansion of blood vessels.

Depending on what you drank and how much, your hangover may include these symptoms:

• thirst
• headache
• muscle aches
• diarrhoea
• nausea
• fatigue
• weakness
• trembling or shaking
• rapid heart rate
• increased blood pressure
• dry mouth and eyes
• poor concentration
• increased sensitivity to light and sound
• a feeling that the room is spinning, or a sense of dizziness
• anxiety, depression, irritability and other mood disturbances
• poor, restless or less sleep.

Most hangovers typically start once your blood alcohol level starts to return closer to zero. Hangovers generally only last up to 24 hours, and go away on their own.

Hangovers are more likely or may be more severe if you:

• drink on an empty stomach (so it’s a good idea to eat before and while you drink alcohol)
• use other drugs while drinking (smoking nicotine is known to make a hangover worse)
• sleep poorly after drinking (alcohol may worsen your sleep which may in turn worsen your hangover)
• drink dark coloured alcohols, such as brandy, rum or whiskey.

Pacing yourself (aiming to drink one drink or less every hour), and drinking water between alcoholic drinks may reduce the severity of a hangover.

Hangovers usually pass with time, but these tips may help to ease symptoms:

• Sip water or fruit juice to stay hydrated.
• Eat something. Plain or bland foods, such as soup or toast, may be easier on a fragile stomach.
• Take a pain reliever. (A standard dose of an over-the-counter pain reliever such as paracetamol may ease your headache, but aspirin can irritate your stomach.)
• Sleep it off.

If you are regularly experiencing hangovers, or hangovers are affecting your relationships, work or life in general, talk to your doctor about potentially cutting back your drinking.

Alcohol poisoning emergency

Sometimes heavy drinking results in the much more serious effect of alcohol poisoning. This is a life-threatening emergency. Call 000 for emergency care if you see these signs in someone who has been drinking:

• confusion
• vomiting
• seizures
• slow breathing (less than eight breaths a minute) or irregular breathing (a gap of more than 10 seconds between breaths)
• blue-tinged skin or pale skin
• low body temperature (hypothermia)
• difficulty remaining conscious
• passing out (unconsciousness) and can't be woken.

If someone is unconscious or cannot be woken up, they could be at risk of dying. If you suspect someone has alcohol poisoning – even if you don't see the signs and symptoms – seek immediate medical attention.

The long-term effects of alcohol

Historically it has been believed that consuming on average more than two standard drinks a day is what can cause many long-term health problems and other harms. Nowadays, current research states that any level of alcohol consumption can pose an increased risk of chronic disease development.

The World Health Organization (WHO) says alcohol contributes to more than 200 different types of diseases and injury.

Some of the most common alcohol-related harms include:

• road and other accidents
• domestic and public violence
• crime
• family breakdown
• social dysfunction
• cardiovascular disease
• cancers, including of the oral cavity, pharynx, larynx, oesophagus, liver, colorectum and female breast
• diabetes
• nutrition-related conditions, such as folate deficiency and malnutrition
• overweight and obesity
• risks to unborn babies
• liver diseases
• mental health conditions, such as anxiety and depression, and interference with antidepressant medication
• alcohol tolerance and alcohol dependence or addiction
• long-term cognitive impairment
• self-harm (suicide).

The WHO reports that in 2016, 5.3 per cent of all deaths globally were caused by alcohol consumption. Worldwide, more men die as a result of alcohol consumption than women.

In the long term, alcohol consumption can affect all aspects of a person’s life: their physical and mental health, work, finances and relationships.

What is binge drinking and how does it affect your body?

Generally, binge drinking means drinking heavily over a short period of time with the intention and result of getting immediately and severely intoxicated (drunk).

In the short term, binge drinking may result in a hangover, alcohol poisoning, or any of the other short-term effects of alcohol consumption, such as accidents and violence, discussed above.

In the long term, binge drinking may result in any of the long-term effects of alcohol consumption, such as heart disease, cancer, liver cirrhosis and diabetes.

How to avoid or reduce the effects of alcohol on your body

The best way to avoid the effects of alcohol on your body is to not drink alcohol. This is especially important if you are trying to get pregnant, or you are pregnant or breastfeeding, as there is no safe level of alcohol use that has been identified.

If you choose to drink alcohol, low level drinking is better for your body than heavy drinking or binge drinking.

Australia’s national guidelines to reduce health risks from drinking alcohol from the National Health and Medical Research Council say that the lifetime risk of harm from drinking alcohol increases the more you drink. For healthy men and women, they advise:

• Drinking no more than 10 standard drinks per week reduces the lifetime risk of harm from alcohol-related disease or injury.
• Drinking no more than four standard drinks on any one day reduces the risk of alcohol-related injury arising from that occasion.
• The less you choose to drink, the lower your risk of alcohol-related harm. For some people not drinking at all is the safest option.

See the guidelines for more advice on levels of drinking, or read this fact sheet from The Alcohol and Drug Foundation .

If you would like to cut down on your alcohol consumption, the following tips may help.

It is important to monitor your alcohol consumption as part of a healthy diet. Alcohol consumption has the potential to cause weight gain and obesity, depending on how much someone drinks, the type of drink consumed, as well as the makeup of each individual and a number of other interpersonal factors. You may like to read some more about alcohol consumption and risks .

Where to get help

Not every experience with alcohol is the same for everyone. There are different factors that can affect how individuals’ bodies absorb and metabolize alcohol. Given the same exact amount of alcohol, different peoples’ level of intoxication varies according to situational, physiological and biological factors.

Gender

Biological sex is one factor that can influence how intoxicated an individual gets. Overall, alcohol is metabolized at a different rate in women than it is in men. The differences in anatomy and body composition contribute to the different alcohol experience. Reputable research and numerous studies have also shown that women have fewer of the enzymes used to metabolize alcohol, alcohol dehydrogenase and acetaldehyde dehydrogenase than men do. In fact, most men have 40% more of these enzymes than women. Many other health conditions can also decrease the human body’s ability to process alcohol and therefore present increased health risks and impact how intoxicated an individual gets.

Body Weight

Another factor that can influence how intoxicated someone gets is body weight. This is why men, more often than not, can handle more alcohol in their system than females, as males tend to weigh more. An individual’s body weight determines the amount of physical space through which alcohol can diffuse in the body. For example, a person who weighs 200 pounds will have a lower blood alcohol concentration than a 160-pound person who drank the same amount. Smaller stature individuals will become impaired faster from consuming alcohol.

Alcohol can be distributed throughout the body via the circulatory system and enters most tissues, except bone and fat, which is adipose tissue. Because of this, body composition is a significant factor in how intoxicated a person can get, because as the percentage of body fat increases, the resulting concentration of alcohol in the lean tissues of the body is proportionally higher. Alcohol is more soluble in water than in fat, and muscle tissue is rich with water. If an individual has more muscle than fat, then their alcohol tolerance should increase.

Interactions With Other Drugs

Of course, when individuals mix recreational drugs with alcohol, the experience they are accustomed to with alcohol will be altered.

Drugs that are used for medical purposes can also have adverse effects when combined with alcohol. Certain medications can also have unpredictable interactions with alcohol. Something as innocent as Tylenol can cause major liver troubles if paired with alcohol. It is essential to ask your pharmacist or research any over-the-counter drugs you’re taking in order to understand the possible interactions before drinking. Unfortunately, in some cases, these interactions can be fatal. If you are unaware of how your medication interacts with alcohol, then it is wise to avoid alcohol while taking these medications.

Some drugs are more specific to this risk because of the specific properties of the drugs. For instance, marijuana can reduce nausea, which can inhibit the human body’s ability to remove harmful toxins by vomiting. Because of this, marijuana has the potential to increase the threshold required to elicit a vomit response.

The reason why over-the-counter drugs like Advil and Tylenol are dangerous when mixed with alcohol is that these drugs are also metabolized by the liver. Advil and Tylenol are not in their active form when taken, but they are then transformed in the liver into the active agent. Drinking alcohol while taking these painkillers creates a “bottleneck” in the liver. The drug is then processed incorrectly and the byproducts kill liver cells. As a result, alcohol is metabolized slower.

It is also important not to mix alcohol with other depressants, which includes some antihistamines, which can make the individual drowsy and at risk for accidents or physical harm. Most importantly, when prescription drugs are combined with alcohol, an individual may experience increased impairment. Such results can include a dangerously reduced heart rate and lowered blood pressure.

Food Consumption

Another factor that can influence how intoxicated an individual gets is how much food is in their stomach. This can be very dangerous for those who struggle with eating disorders or those who often forget to eat before a big night of drinking. Drinking on an empty stomach compared to eating before or during drinking causes significant differences in the effect of alcohol on the human body. The scientific explanation for this difference is that drinking on an empty stomach irritates the human digestive system and results in more rapid absorption of alcohol. Eating high-protein foods along with alcohol, as well as before drinking, can help individuals avoid getting too drunk.

The reason why having food in the stomach is important is that substantial stomach contents help slow the absorption of alcohol into the bloodstream and delay impairment. Although debated, the type of food, whether carbohydrate, fat, or protein, has not been shown to have a significant influence on blood alcohol content (BAC). However, it is known that larger meals closer to the time of drinking can lower the peak blood alcohol concentration. Food influences how intoxicated an individual can get because the food could obstruct the alcohol from entering the bloodstream or inhibit the stomach from emptying into the small intestine.

Dehydration

Dehydration is another culprit of how intoxicated an individual gets. The more alcohol individuals have consumed, the more dehydrated they will get.

Alcohol in the bloodstream causes the pituitary gland in the brain to block the creation of vasopressin, a pituitary hormone that acts to promote the retention of water by the kidneys and increase blood pressure. As a result of limited vasopressin, the kidneys send water directly to the bladder rather than reabsorbing filtered water into the bloodstream. This diuretic effect increases as the blood alcohol content increases and can lead to dehydration. Additionally, studies have shown that drinking 250 mL of an alcoholic beverage causes the human body to urinate between 800–1000 mL, resulting in the body releasing more than just liquid being consumed.

Interestingly, carbonation speeds up absorption. Alcohol mixed with carbonated beverages such as soda or tonic water will be absorbed faster into the bloodstream. This applies to champagne and wine coolers as well.

Additionally, since energy drinks are stimulants and alcohol is a depressant, energy drinks mask the effects of alcohol by giving drinkers a sense of energy and a false sense that they are not that intoxicated. Mixing alcohol and energy drinks can even lead to heart failure because they are opposing stressors on the human body’s regulatory systems.

Method of Consumption

The way a person consumes alcohol can influence how intoxicated the person gets. The more alcohol a person drinks within a short period of time, the more they overtax their body’s ability to metabolize the alcohol. This is applicable to what happens when an individual takes shots of hard liquor. It is better to sip and drink more slowly to spread your drinking out over time in order to control how intoxicated you become. The amount of alcohol and speed of consumption matters. Basically, the more alcohol and the shorter the time period, the higher the individual’s Blood Alcohol Content (BAC) will be.

Other Influential Factors

There are also very unique characteristics that can influence how intoxicated you get. First, heritable components of enzyme production can be a determining factor. Typically, individuals of Asian or Native American descent display reduced levels of alcohol dehydrogenase, meaning that alcohol will remain in their blood longer and high concentrations of toxins can build up faster. Secondly, if an individual is sick or just getting over an illness, they will tend to become impaired more quickly. Third, strong emotions such as anger, fear, and loneliness tend to enhance impairment.

Women who take some form of birth control pills or are in their premenstrual time in their cycle may have a higher BAC. Additionally, if an individual is lacking sleep or is tired, then they will become impaired more quickly than if they were well-rested. For example, if an individual gets five or fewer hours of sleep for four nights in a row, two drinks may start to feel like six drinks. Lack of sleep reduces tolerance, so individuals will experience impairment at lower BAC levels than normal.

In short, there are no hard and fast rules for how intoxicated an individual gets. Every individual can experience a combination of influencing factors at once. Therefore, it’s very important to drink responsibly or stay sober since everyone is at risk based on their own unique composition.