Gout is a painful condition that affects the joints of men and women. The incidence of gout has been increasing in the developed world for the past 30 years. It has been thought for a long time that drinking alcohol increases your risk of developing gout, but the theory has never been proven.
An american study, published in the Lancet, looked at 50,000 men and found that drinking alcohol is linked with an increased risk of developing gout. In addition, it appears that the type of drink also makes a difference: beer appears to be more “risky” than wine.
What did the study look at?
The study was published in the Lancet by researchers at the Massachuetts General Hospital. The 12-year study assessed the lifestyles of 47150 men who did not have gout and followed them to see if they developed gout. Over the course of the study 730 men developed gout.
By looking at the amount of alcohol the men drank the study’s authors produced valuable information about the association between alcohol and gout. Also, by looking at the types of drink the men drank, the study’s researchers have drawn conclusions about the role different drinks play in raising the risk of developing gout.
What is gout?
Gout is the most common inflammatory arthritis in men. It is caused by uric acid crystals being deposited in the joints. The build up of these crystals stimulates the body’s immune system and causes an intense inflammatory reaction. People with gout have swollen and very painful joints – often starting in the big toe.
The incidence of gout has been rising in the developed world for the past 30 years. It is thought that this is due to number of factors:
- doctors diagnosing gout more often
- changes in lifestyle, such as being less active
- changes in diet, including drinking more alcohol and eating more red meat
- change in social behaviour, for example the increased use of labour-saving devices
It is also known that gout does have a genetic basis, but this is unlikely to account for the rise of gout.
Why did the researchers look at the link between alcohol and gout?
It has always been believed that drinking alcohol raises the risk of developing gout, but no large-scale study had ever been conducted to prove or disprove the theory. This study is the first large-scale investigation of such a link and proves that alcohol does play role.
How is alcohol thought to increase the risk of gout?
Gout is due to the deposit of uric acid in the joints and drinking alcohol can increase the levels of uric acid in the body. This increase in uric acid increases the risk of build up in the joints.
There are two main ways in which uric acid levels can build up in the body:
- less removal of uric acid from the body through the kidneys
- more production of uric acid in the body.
Alcohol may affect both uric acid removal and production:
- it is thought that when alcohol is converted to lactic acid, it reduces the amount of uric acid that is removed from the body through the kidneys. This is because the lactic acid competes with the uric acid for removal from the kidneys into the urine
- it is also thought that increased levels of ethanol (alcohol) in the body increases the body’s production of uric acid by increasing the amount of ATP that is converted to AMP – a precursor of uric acid.
How were men’s levels of alcohol intake measured in the study?
The authors used standard portions to measure alcohol consumption among the men they studied:
12oz (355ml) bottle or can of beer – containing 12.8g of ethanol (alcohol)
4 oz (118ml) glass of wine – containing 11.0g of ethanol (alcohol)
1 Shot (44ml) of spirits – containing 14.0g of ethanol (alcohol)
The researchers then calculated the men’s overall consumption of alcohol by adding up their different drinks.
What were the findings of the study?
Link between drinking alcohol and gout
When compared with people who drink no alcohol:
The risk of gout was significantly raised with alcohol intake as low as 10.0-14.9g per day. This is the equivalent of just one drink per day.
The risk of gout was 2.5 times higher among men who consumed 50g or more per day.
Compared with people who drink no alcohol:
10-15g per day increased risk by 30 percent
15-30g per day increased risk by 50 percent
30-50g per day increased risk by 100 percent
More than 50g per day increased risk by 150 percent
Gout and type of drink
However, the increase in risk of developing gout with increasing alcohol intake was not the same for each type of drink:
- two or more bottles of beer per day increased the risk of gout by 2.5 times compared with no beer intake
- two shots of spirits per day increased the risk of gout by 1.6 times compared with no spirit intake
- two glasses of wine was not associated with an increase in the risk of gout when compared with no wine intake.
Increase in gout risk per serving of type drink
The differences in the risk of developing gout by type of drink were also seen in the increase in risk per serving of each type:
- beer increased the risk of gout per serving per day by 49 per cent
- spirits increased the risk of gout per serving per day by 15 per cent.
The fact that the increase in gout risk per serving of beer is higher than that for spirits is surprising because spirits contain more alcohol per serving than beer. Because of this, the researchers argued that there might be another, non-alcoholic, ingredient in beer that was helping to increase the risk of gout.
Why is beer more risky than spirits or wine?
The study’s researchers propose that beer’s greater association with gout could be due to other, non-alcoholic, ingredients in beer. The researchers pointed out that beer is the only alcoholic drink to contain chemicals known as purines. These chemicals are thought to play a role in gout. Because of this, the authors argue that these purines could be contributing to the increased risk seen with drinking beer.
However, this argument has been challenged by other doctors who point out that the evidence for purines playing a role in gout is not conclusive. They refer to a previous study of Taiwanese vegetarians who ate a diet that is high in purines: these people actually had a reduced risk of developing gout. These doctors say that there could be other reasons why beer drinkers are at a greater risk than wine drinkers – see below.
Can different drinks really have different risks?
The study’s researchers argue that the type of drink could have a direct effect on the risk of developing gout, due to the non-alcoholic ingredients in the drink. However, this has not been proven and other doctors think that other factors, not related to the type of drink, are causing the difference in risk.
Those doctors who disagree with the idea that the drinks themselves have different risks suggest that the type of drink you choose to consume reflects other diet and lifestyle choices you may have made. It could be that people who drink beer may choose to exercise less or eat more risky foods than people who drink wine – and it could be these diet and lifestyle differences that account for the difference in risk between types of drink.
So is wine a “safe” option?
Because it is not known whether or not it is the type of drink or other lifestyle choices that are responsible for increasing the risk of gout, it is impossible to say that wine is a “safe” option.
It is also worth noting that the authors of the study cannot rule out the possibility that drinking more than two glasses per day of wine could increase the risk of gout.
What are the current UK Government recommendations for safe drinking?
Sensible drinking limits are defined as no more than 21 units a week for adult males and 14 units a week for adult females.
To reduce health risks from drinking, this should be spread over the week, no more than 3-4 units per day for men and no more than 2-3 units a day for women.
One unit is defined as 7.9g of ethanol (alcohol). This is roughly the same as:
- half a pint of beer, cider or lager
- a 25ml (pub) measure of spirit such as vodka, whisky or gin
- a 50ml (pub) measure of fortified wine such as port or sherry
- a small (125ml) glass of wine.