Alcohol and arteries

Written by: 
Dr Sarah Brewer

We all know that excessive alcohol intake is bad for us, but if we can keep to just moderate drinking it has benefits versus not drinking at all. What are these benefits and exactly how much is moderate drinking? This page explains

Many studies around the world have suggested that a moderate intake of alcohol reduces the risk of developing heart disease.

In addition, people who are moderate drinkers have a lower risk of dying if they do experience a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction., and a lower risk of experiencing a second heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. in the future.[1],[2]

Interest in the effects of alcohol in protecting the heart arose because of the 'French paradox'. The main benefits are in relation to heart disease and arterial disease. Only moderate drinking delivers these benefits, and they do not apply equally to all people.

Discussions of moderate drinking are complicated by the fact that different national health authorities use different terms and measures.

  • In the UK, health authorities talk of units of alcohol while in the USA and some other countries, authorities use the term standard drinks
  • A standard drink or unit varies significantly between countries - in the Netherlands a drink contains 9.9g alcohol, in the USA 14g alcohol, in the UK one unit is 8g alcohol and in Japan a drink contains 19.75g alcohol.

See Different recommendations.

'French paradox'

Compared with people in the UK and the USA, the French eat as much saturated fatOne of the three main food constituents (with carbohydrate and protein), and the main form in which energy is stored in the body., have similar high cholesterolA substance present in many tissues and an important constituent of cell membranes although high concentrations of a certain type of cholesterol in the blood are unhealthy. levels, smoke as much (if not more), take as little exercise and drink significantly more wine, yet their risk of heart disease is lower.

Researchers concluded that the most obvious explanation for this paradox lay in French people's red wine consumption. More recent data suggests that any form of alcohol - beer, wine or spirits - can prove beneficial, but only in moderation. Read more about Fats in your diet.

Alcohol and heart disease

Many studies show that the link between alcohol and coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease forms a 'J'-shaped curve.[3] This means that:

  • People benefit from drinking at low to moderate levels
  • Once past a certain level of intake drinking more is harmful and significantly increases the risk of heart disease.

A European meta-analysis of data from 34 studies involving more than 1 million people showed that risk of heart disease decreased with an intake of up to 2 drinks a day for women and up to 4 drinks a day for men, but the maximum protection was seen at a dose of 6g alcohol - approximately half a drink per day.[4] For more information on the size of a drink in terms of units of alcohol see Different recommendations.

Higher intakes of alcohol were associated with increased mortality, and these adverse effectsUndesirable side-effects of medication. were seen at lower doses in women.

One possible reason why the benefits of alcohol disappear at a lower dose in women than in men is that pre-menopausalRelating to the menopause, the time of a woman’s life when her ovaries stop releasing an egg (ovum) on a monthly cycle. women may gain less benefit from drinking alcohol because they are already protected against coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease by the hormoneA substance produced by a gland in one part of the body and carried by the blood to the organs or tissues where it has an effect. oestrogenA hormone involved in female sexual development, produced by the ovaries..

Alcohol and arterial disease

Alcohol appears to have a beneficial effect against hardening and furring up of the arteries - a process known as atherosclerosisDisease leading to fatty deposits in the inner walls of the arteries, which reduce and may eventually obstruct blood flow..

In particular, alcohol appears to have beneficial effects on levels of 'good' HDL-cholesterolA substance that mainly exists to carry cholesterol from the circulation to the liver; commonly referred to as 'good cholesterol'. and on a bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. clotting factorA substance that can undergo a cascade of reactions in certain conditions, leading to the clotting of blood. Also known as coagulation factor. called fibrinogenA coagulation factor, a substance in the blood that brings about clotting., and on arterial calcificationCalcium deposited in tissues and organs. . Read more about 'good' and 'bad' cholesterol and atherosclerosisDisease leading to fatty deposits in the inner walls of the arteries, which reduce and may eventually obstruct blood flow..

Increased levels of 'good' HDL-cholesterol

Pooled results from 42 different studies show that an intake of 30g alcohol a day from beer, wine or spirits increases concentrations of 'good' HDL-cholesterolA substance that mainly exists to carry cholesterol from the circulation to the liver; commonly referred to as 'good cholesterol'. by 0.10 mmol/lMillimoles per litre - units of the amount of substance present. (3.99mg/dl) - enough to lower the risk of heart disease by 24.7 per cent.[5]

Reduced levels of fibrinogen

Alcohol has a bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid.-thinning effect because it reduces levels of the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid.-clotting factorA substance that can undergo a cascade of reactions in certain conditions, leading to the clotting of blood. Also known as coagulation factor. fibrinogenA coagulation factor, a substance in the blood that brings about clotting. in the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid.. These reduced levels occur at intakes of up to 20g alcohol per day for women and up to 30g per day for men.[6]

Reduced calcification

Atherosclerosis is linked with the laying down of calciumAn element that forms the structure of bones and teeth and is essential to many of the body's functions. (a process known as calcificationCalcium deposited in tissues and organs. ) in arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. walls, and can be assessed using computed tomography (CTA scan that generates a series of cross-sectional X-ray images.) scanning. Compared with non-drinkers:

  • People who consume 1 alcoholic drink or less per day have a 40 per cent reduction in extensive calcificationCalcium deposited in tissues and organs. of coronaryRelating to the arteries supplying the heart itself. arteries
  • People who drink 1 to 2 alcoholic drinks per day have a 50 per cent reduction
  • People who drink more than 2 alcoholic drinks per day have a reduction of only 10 per cent.[7] This research was performed in the Netherlands, where one drink is 9.9g alcohol.

Slower progression of arterial disease

A moderate intake of alcohol may reduce the progression of established arterial disease.

Among patients who had previously undergone coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft surgery, for example, moderate drinking - between 7 and 13 drinks per week - was associated with a trend towards fewer heart events and reduced progression of atherosclerosisDisease leading to fatty deposits in the inner walls of the arteries, which reduce and may eventually obstruct blood flow. as seen on an angiogramAn X-ray image of the blood vessels following the injection of a dye to improve visibility..

Researchers found that increased levels of 'good' HDL-cholesterolA substance that mainly exists to carry cholesterol from the circulation to the liver; commonly referred to as 'good cholesterol'. accounted for one-third of the trend towards lower risk.[1] This research was performed in the Netherlands, where one drink is 9.9g alcohol.

Moderation is the key

Moderate drinking may benefit certain people, especially men over 40 and postmenopausal women.[8]What counts as moderate consumption varies between countries.

Drinking alcohol cannot be recommended as a treatment for arterial disease or heart problems, however.

Excessive alcohol intake is associated with an increased risk of sudden death (due to abnormal heart rhythms), high bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. pressure, enlargement of the heart (alcoholic cardiomyopathy), cancerAbnormal, uncontrolled cell division resulting in a malignant tumour that may invade surrounding tissues or spread to distant parts of the body. and strokes.[3]It also damages the liverA large abdominal organ that has many important roles including the production of bile and clotting factors, detoxification, and the metabolism of proteins, carbohydrates and fats..

In addition, recent research suggests that the benefits of moderate alcohol intake do not apply equally to all people.

The benefits are most evident in those who follow a generally unhealthy diet and lifestyle, who take little exercise or who smoke. Little additional benefit from alcohol is seen in those who do not smoke, eat fruit and vegetables daily, and who exercise for 3 or more hours per week.[10]

Different recommendations [10]

Country Recommended daily maximum (grams alcohol) Equivalent number of drinks (at the standard drink size for that country)
  Men Women Men Women
Australia 40 20 4 2
Canada 13.5 13.5 1 1
Japan 39.5 n/a 2 n/a
Netherlands 18-27 2 or 3 times a week (men and women)   2-3 2-3
New Zealand 30 20 3 2
UK 24-32 16-24 3-4 2-3
USA 28 14 2 1
References: 
  1. Mukamal KJ, Girotra S, Mittleman MA. Alcohol consumption, atherosclerotic progression and prognosis among patients with coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass grafts. Am Heart J 2006;151(2):368-72. Link
  2. Mukamal KJ, Maclure M, Muller JE et al. Prior alcohol consumption and mortality following acuteHas a sudden onset. myocardial infarctionDeath of an area of heart muscle due to poor blood supply., JAMA 2001; 285:1965-1970. Link
  3. Kloner RA, Rezkalla SH. To drink or not to drink? That is the question. Circulation 2007;116(11):1306-17. Link
  4. Di Castelnuovo A, Costanzo S, Bagnardi V et al. Alcohol dosing and total mortality in men and women. Arch Intern Med 2006;166:2437-2445. Link
  5. Rimm EB, Williams P, Fosher K et al. Moderate alcohol intake and lower risk of CHD: meta-analysis of effects on lipids and haemostatic factors. BMJ 1999; 319(7224):1523-8. Link
  6. Burger M, Mensink G, Bronstrup A et al. Alcohol consumption and its relation to cardiovascular risk factors in Germany. Eur J Clin Nutr 2004;58:605-614. Link
  7. Vliegenthart R, Oei HS, Van den Elzen APM et al. Alcohol consumption and coronaryRelating to the arteries supplying the heart itself. calcificationCalcium deposited in tissues and organs. in a general population. Arch Intern Med 2004;164:2355-2360. Link
  8. 'Alcohol and heart disease'. British Heart Foundation. Link
  9. Britton A, Marmot MG, Shipley M. Who benefits most from the cardioprotective properties of alcohol consumption - health freaks or couch potatoes? J Epidemiol 2008;62(10)_905-8. Link
  10. International Centre for Alcohol Policies (ICAP). ICAP Reports 1 - Supplement: Safe Alcohol Consumption. Link