Dry January – The Health Effects of Alcohol

As part of Dry January, Alison Metcalfe who leads the NHS Business Services Authority’s (NHSBSA) professional and clinical services writes about the importance of understanding how alcohol affects your body in both the short and long term, and how you can limit the potential risks. 


Hi there, I’m Alison Metcalfe and I am Head of Professional and Clinical Services in NHSBSA and I also lead our NHSBSA Clinical Network. We’re really pleased to be supporting ‘Dry January’ with a series of blogs highlighting issues around alcohol, from a general health and wellbeing perspective, to more specific issues around dental and eye health and potential interactions with other drugs and medications.

The beginning of a new year is always a time to make new resolutions about your health, particularly after the excesses of Christmas. Now is a great time to be thinking about your relationship with alcohol and making it a healthy one for 2021 and beyond.   

The basics – what is alcohol and why is it harmful?

In 2019 the cost to the NHS of alcohol-related illness was estimated to be £3.5 billion per year. Research showed that there are more than one million alcohol-related hospital admissions every year in England alone. And this represents, not just a burden on the health service, but far reaching and costly impacts on an individual, their families, and their relationships.

Alcohol is a powerful chemical which can enter every cell of your body, disrupting normal functioning and affecting almost every part of your body, giving rise to both visible and invisible effects. These can have both short and long-term impacts on our health and wellbeing – physical, mental and social.  And as levels of drinking rise, so does the risk of problems.

The alcohol we drink is ethanol which, generally, comes from the fermentation of fruit and grains. Once it’s in your body it gets into the blood stream quickly. As your body recognises it as something harmful it diverts resources to get rid of it. The liver does most of the ‘heavy lifting’, putting extra pressure on the liver, digestive, and cardiovascular systems especially. As alcohol is also a depressant, it slows things down impacting particularly the brain and central nervous system.

Until the alcohol can be cleared from your body it will disrupt normal function, giving rise to a myriad of short-term effects depending on the amount of alcohol in the blood stream. At the same time, this all begins to open the door to longer-term impacts.

What’s the basic guidance?

While there is no ‘safe’ drinking level, the advice of the UK Chief Medical Officer is to keep health risks to a low level by not drinking more than  14 units of alcohol a week on a regular basis, for both men and women.

That’s six pints of medium strength (4%) beer or six 175ml glasses of wine (13.5%).

And if you do regularly drink as much as 14 units per week, you should spread it evenly over three or more days. One or two heavy drinking episodes a week increases your risk of long-term illness or injury.

Source: Drinkaware – health effects of alcohol (


To reduce the short-term health risks of drinking, you should drink slowly and with food, alternating an alcoholic drink with water.

If you’re pregnant or think you could become pregnant, the safest approach is not to drink alcohol at all to keep risks to your baby to a minimum.

In the short term…

When alcohol gets absorbed into your blood it increases your heart rate, reduces your blood pressure, and expands your blood vessels. You can also become warm, sociable, and talkative.

By continuing to drink, your brain and nervous system start to become affected before the liver has a chance to clear the alcohol, this can affect your judgement and decision making – you can become more reckless and uninhibited. You become light-headed and your reaction time and coordination are affected.

If you continue to drink, the depressant effects of the alcohol will make you drowsy and can eventually lead to alcohol poisoning where high levels of alcohol start to interfere with automatic functions such as your breathing, heart rate, and gag reflex.

These short-term effects can put not just your health at risk, but also your safety as the risk of accident and unintentional harm increases.

In addition, alcohol is a great source of ‘empty calories’ – calories with no nutritional value but which can pile the weight on. In making you pass more urine,  it dehydrates you which contributes to that ‘hangover’ the following day and it also disrupts normal sleep patterns. So, while it may help you get off to sleep, you’ll end up feeling exhausted and unrefreshed.

In the longer term…

The bottom line is that regular drinking above the recommended level increases your risk of earlier death and developing cancers and chronic, long-term conditions. And the more you drink, the higher the risk.

recent studies suggests a lowered life expectancy the more that you drink above 12 units per week, an increased risk of developing hypertension (raised blood pressure), coronary artery disease, and of having a stroke. There’s also an increased risk of developing liver disease, dementia, and cancer – particularly cancers of the bowel, head and neck, liver and breast.   

From a mental health perspective, while in the short term you may be tempted to use alcohol to relax and relieve stress, it’s actually associated with increased levels of anxiety, depression, and isolation as well as family and relationship problems. Persistent high levels of drinking can also lead to addiction and withdrawal.

What to do if you are concerned

You should try having several drink-free days each week, but don’t make up for it on the days you do decide to have a drink!

There’s lots of help available for you:

  • has a lot of helpful information on alcohol misuse treatment.
  • Also organisations such as Drinkaware have lots of advice, support, and online tools to help you assess and reduce your drinking. They can also help you get your relationship with alcohol on a healthier footing.
  • Learn more about Dry January
  • And don’t forget: you can also contact your GP to discuss any concerns.