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The molecular structure of alcohol
  • Alcohol is a chemical substance that can be found in alcoholic drinks, household products, fuel, and much more.

    An alcoholic drink is one that contains ethanol, which is a form of alcohol that is produced by the fermentation of grains, fruits, or other types of sugar. When alcohol is consumed, it is a psychoactive drug that acts as a depressant for the central nervous system.

  • The 4 types of alcohol are isopropyl alcohol, methyl alcohol, undistilled ethanol, and distilled ethanol. Distilled ethanol and undistilled ethanol can be consumed.

    Yeast or bacteria chemically convert sugars into ethanol through the process of fermentation. Sugars that are used to produce ethanol can come from barley, wheat, grapes, or other grains and fruits depending on the type of drink being created. Fermented beverages can be drunk directly, or can be further distilled to a higher alcohol percentage.

    Examples of distilled ethanol include Vodka, gin, brandy, whiskey, rum, and tequila are some of the best-known distilled drinks, and typically have an ABV of around 40%.

    Examples of undistilled ethanol include beer, wine, and cider, which typically have an ABV of no higher than 15%

    On the other hand, both isopropyl and methyl alcohol should not be consumed.

    Isopropyl alcohol is typically used for disinfection purposes.

    Methyl alcohol typically is seen in things like paint, solvents, printing ink, etc

  • Alcohol has a few different functions in the brain. It represses an excitatory neurotransmitter, glutamate, and increases an inhibitory neurotransmitter, GABA. This means that one’s thoughts, movements, and speech are impaired, and become more impaired as consumption increases. Alcohol’s repressive effect as a nervous system depressant, means that it slows down parts of the brain. Areas that it affects include those that control inhibition, thought, perception, attention, judgement, memory, sleep and coordination.

    However, alcohol also increases the release of the neurotransmitter dopamine, which is known for its role in the “reward system” of your brain. This causes your brain to think it is having a good time, and therefore one may continue to drink to chase the release of dopamine. However, with consistent exposure the effects of dopamine begin to diminish. At this point, one is often attached to the effects of dopamine so they continue to drink with the hopes of feeling the “high”, despite not receiving it.

  • Though different for everyone, depending on factors such as gender, size, metabolism, etc, alcohol can cause: memory loss, slurring of speech, impaired judgment, vomiting and nausea, sleepiness, breathing issues, loss of consciousness, issues with bladder and bowel control, and even coma or death. With long-term alcohol abuse, heart issues such as cardiomyopathy (stretching of heart muscles) or arrhythmias (irregular heart beats) can occur, as well as a multitude of liver issues.

    The effects of alcohol on behaviour depend on the level of alcohol in the blood:

    • Low blood-alcohol-concentration will depress parts of the brain involved in inhibition, making the user more animated and social. It may also lift your mood, but even at low levels alcohol can still affect coordination and judgement. Alcohol in a social context often helps people to be happier and more confident. Tipsy people can be chatty and giggly, although some may become withdrawn. Alcohol often makes people say and do things they normally wouldn’t (reduces inhibitions). When people aren’t at bars, clubs and parties, many people consume alcohol for its calming effects, for example, wine with an evening meal. Many people say they enjoy alcoholic drinks for the taste, rather than using it as a drug. However, the taste of alcoholic drinks is usually unpleasant to people when they first try them and later enjoyment of the taste may be a learned association with the drug. After a couple of drinks, people start to lose the ability to concentrate and think straight.

    • Higher concentrations of alcohol will begin to seriously hamper coordination, memory and judgement. Alcohol also depresses the ability to regulate emotion, which is why intoxicated people can become emotional or aggressive.

    • Large enough concentrations of alcohol in the blood will cause users to become woozy and they may pass out. A potentially fatal concentration of alcohol in the blood will depress areas of the brain involved in breathing, causing breathing to slow dramatically and eventually stop.

    Alcohol also causes the user to urinate more, causing dehydration. Following heavy use of alcohol the user may experience a ‘hangover’, which typically is experienced the morning after (although a hangover can last longer). Effects of a hangover can include: nausea and vomiting, headache, thirst, sensitivity to light and noise, diarrhoea, low mood and anxiety. People can generally be described as not being at their best on a hangover, and studies have found things like memory to be worse during a hangover.

  • Alcohol at high concentrations is quite toxic, which makes it useful for killing germs. Alcoholic hand gels and wipes are an essential means of preventing infection, and mouthwashes often use alcohol too. However, drinking alcohol doesn’t work to cure infectious diseases.

    It has been suggested that alcohol in moderation could have some health benefits (see alcohol myths and misunderstandings below). However, any suggested health benefits are outweighed by the potential damage to your health.

    Historically, alcohol was used to stupefy people before having painful operations such as getting their teeth pulled out.

    Ethanol has also been used as an antidote to poisoning by methanol, a more toxic alcohol chemical which causes blindness and death.

  • There are many risks associated with drinking alcohol, both at time of consumption and over time. Alcohol consumption not only causes an increased risk of a multitude of health issues, but the effects of alcohol can also be seen in an increase in violence (such as suicide, homicide, or sexual assault), or injuries (falls, drownings, vehicle accidents). Amongst the most common injuries are those associated with accidents caused by drunk drivers.

    Over time, excessive alcohol use can lead to a variety of heart issues, an increase in the likelihood of cancer, memory and learning issues, an increase in severe mental health issues, and a weakening of the immune system.

    Most risks associated with drinking alcohol can be avoided by not consuming copious amounts and not drinking on a frequent basis.

  • Alcohol causes and worsens many health conditions, especially when consumed frequently and/or in large amounts. If you have high blood pressure, cardiovascular disease, liver conditions, conditions that make you bleed easily, mental health issues, or any other serious health problems, alcohol may cause you greater harm than it does the average person. If you are concerned, always discuss alcohol consumption with your doctor to better understand how it would impact you specifically.

    Drinking whilst pregnant can cause harm to the foetus, particularly when alcohol is consumed in the beginning of the pregnancy. This is known as foetal alcohol syndrome and can cause brain damage, growth issues, or facial abnormalities.

  • Consuming alcohol with any other drugs increases the risks of unpredictable consequences. Drinking alcohol and consuming depressants such as Valium or Xanax can cause dizziness, stumbling, memory loss, and even death. Drinking and consuming stimulants such as Adderall, can hide the impacts of alcohol which makes it harder for people to gauge their intoxication levels, often resulting in overconsumption. Drinking in combination with taking opiates such as Percocets or OxyContin can cause a decrease in blood pressure and pulse, loss of consciousness, slowed breathing, coma, or even death.

    Drinking and smoking are often closely linked, with a large portion of patients diagnosed with dependence on one diagnosed with dependence on the other. The frequent use of alcohol and tobacco causes a significant increase in the risk of cancers (particularly moth or oesophageal cancer), and cardiovascular diseases.

    Many medical drugs have side-effects when taken with alcohol. Others may not work effectively. Always read the leaflet or check with your doctor.

  • Alcohol dependence, often called alcoholism, is common. Dependence on alcohol means that the user has lost some or all control over their use of alcohol and are likely to suffer withdrawal effects if they don’t drink. This is more common in men, although women who are alcohol dependent usually suffer more severe harms as a result of alcoholism.

    Not everyone who drinks alcohol is equally at risk of becoming dependent. Drinking from an early age and using alcohol as a tool to blot out stress and anxiety are just some factors associated with drinking too much and becoming dependent.


    Alcoholism can run in families, due to both genetic reasons and the influences people are exposed to. Traumatic experiences in early life, such as abuse, increase the chances of becoming alcohol dependent.

  • Being addicted to alcohol (alcoholism, alcohol dependence) makes people particularly vulnerable to the many health harms that alcohol can cause. Addiction changes a person’s priorities, which can be devastatingly disruptive to the lives and wellbeing of the addicted person and their families. People who are worried about alcohol addiction can get help and support by visiting their doctor.

    Mildly addicted people suffer psychologically when they try quitting and may get cravings and feel anxious and miserable without drinking. People who are suffering from alcohol dependence become physically as well as psychologically reliant on alcohol. Physical reliance on alcohol means that a person’s body has adapted to having alcohol in it, and so removing the alcohol causes physical withdrawal symptoms. Quitting can cause flu-like or hangover-like withdrawal symptoms for about 3 days. Withdrawal from more severe alcoholism can have dangerous consequences, especially episodes of delirium tremens, which is potentially fatal. This includes shaking, hallucinations and a racing heart.

    Withdrawal for severe alcohol addiction should only be attempted with medical help.

  • Health harms

    Regardless of addiction status, drinking large amounts of alcohol increases the risk of a variety of diseases. The harms of drinking large quantities of alcohol are associated with other issues, such as a bad diet, depression, and social problems. Alcohol damages the heart, pancreas and other vital organs. The liver, which plays a large role in the body’s detoxification from alcohol, often sees the worst effects of alcohol usage.

    Alcohol is a carcinogen, meaning that it is capable of causing cancer. Alcohol can also cause other issues such as diabetes, hormonal imbalances and even sexual dysfunction.

    Alcohol is particularly toxic to the brain. In adults, alcoholism causes brain shrinkage. Excessive use in older ages increases the risks of developing Alzheimer’s. Long-term alcoholism coupled with malnourishment can cause Wernicke–Korsakoff syndrome, which can leave permanent brain damage with dementia and amnesia (inability to remember).

    Many people with alcohol dependence also suffer from mental illnesses. Mental illnesses may increase the risk of developing alcohol dependence, just as alcohol dependence may increase the risk of developing a mental illness. Some people may drink as a result of their mental illness, while others could develop a mental illness as a result of their alcohol dependence. Often, mental illness and alcohol dependence can be thought of as co-occurring conditions, which is when the conditions occur simultaneously. Co-occurring conditions tend to aggravate each other. When one issue is ignored, the other often worsens.


    Damage to employment, families and communities

    Unhealthy relationships with alcohol often impact others. Addictions make it more difficult to hold down a job and can be damaging to relationships. Alcoholism, like any addiction, takes up time and resources, making it very difficult for homeless and vulnerable-housed people to improve their situation.


    Association with crime and antisocial behaviour

    When people are under the influence of alcohol, they are less able to act with good judgment or control violent impulses. The majority of assaults on young people that lead to hospitalization are related to alcohol consumption, and roughly half of domestic violence occurs after the perpetrator has been drinking. Drunkenness, even when non-violent, uses up police time, accounting for most arrests that occur at night. Very drunk offenders are particularly time-consuming, as they are more likely to be disruptive and uncooperative, and require supervision to ensure their safety.

  • Being aware and in control of what you are drinking is very important to reducing the harmful potential of alcohol. If you know and are aware of what drinks you’ve consumed, it is easier to manage your intake. If you are also drinking water or other hydrating drinks in addition to the alcoholic drinks, it aids your body in the alcohol detoxification process and helps to maintain your mental capacity. It is also important to know your tolerance level.

    Always have alternative transportation options if there is a chance that you might be consuming alcohol. Driving with any alcohol in your system poses risk to not only yourself, but your passengers and other drivers. You can designate a driver, or call a car ride service such as a taxi.

    It is important to recognize not only how much you drink, but also how frequently you drink. The NHS states that the recommended weekly limit is 14 units.

    Loss of consciousness is often a result of consuming large amounts of alcohol. If one loses consciousness, they run the risk of throwing up and potentially choking on their vomit. To avoid this, ensure that the person is lying on their side so that their airway is not blocked. Continue to monitor the person and if they become unresponsive, vomit while unconscious, or have slow breathing, make sure to call emergency services.

  • Does drinking water cancel out the effects of alcohol?

    Drinking water does not protect your liver and other organs from the harm of processing alcohol, but it may help someone in their pace of alcohol consumption. Pacing alcohol consumption makes it less likely that you accidentally consume more than intended. Drinking water also helps to curb dehydration caused by alcohol.


    Is tolerance to alcohol a good thing?

    Tolerance to alcohol is often thought of socially as something positive or indicative of toughness. However, high tolerance levels means that someone will get less drunk, making them likely to drink larger amounts. Large amounts of alcohol make them more at risk of harms like liver disease and alcohol addiction. Tolerance to alcohol also runs in families, which is one of the reasons why alcohol addiction runs in families.


    Does consuming different types of alcohol make you more drunk?

    Mixing drinks can make you feel sick or nauseous. However, drinking different types of alcohol makes it more difficult to gage your intake levels, as different drinks have different ABV levels. Alcohol is often paired with sugary drinks. Both alcohol and sugar cause dehydration and strain to the liver.


    Does coffee sober you up?

    Caffeine may make a drunk person less sleepy and more alert but it does not have the capability to neutralize the alcohol in your system. Drinking coffee to perk yourself up before doing something you would not do drunk (like driving) is a bad idea. Using caffeine-containing energy drinks to keep you going increases the strain on your heart as both caffeine and alcohol have negative cardiovascular effects.


    Is alcohol in moderation good for you?

    There is a common misconception that alcohol, ‘in moderation’, has proven health benefits. In fact, most of the total number of deaths and diseases caused by alcohol happen to people in the large majority of the population who are ‘moderate’ drinkers, not in the minority who are heavy drinkers. No-one should justify their alcohol consumption with the belief that they are benefiting their health.

    There is some controversy and contested evidence about whether light drinking could be protective against specific conditions, like heart disease in middle age. A controlled trial, the only kind of study which could demonstrate this for certain, is impossible. Some observations at the population level (epidemiological research) seem to show that the middle-aged people who are the least likely to die from heart disease are not those who never drink, but those who drink very little. However, this evidence is not enough to prove that drinking a little makes you more healthy than not drinking. Some non-drinkers in the samples may never drink because they have health problems, or because they quit drinking after it harmed their health. The intake of alcohol which appears to be associated with the smallest chance of illness and death is very low, around half a pint of beer or half a glass of wine. Increased harm is observable at levels not much higher than this.

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