Alcohol - evidence
Moderate alcohol may reduce dementia risk, but too much will damage your brain.
Current evidence suggests that enjoying moderate consumption of alcohol may reduce your risk of dementia.
It cannot guarantee you won’t develop dementia, so if you don’t drink for health or other reasons, there is no need to take it up.
Too much alcohol, on the other hand, can damage your brain and lead to an increased risk of developing dementia. Talk to your doctor if you think you might have a problem.
So, if you drink alcohol, do so in moderation. Follow the Australian Guidelines to Reduce Health Risks from Drinking Alcohol and have no more than two standard drinks on any day. Ensuring you drink sensibly will help protect your brain and your cognitive function.
What’s the evidence that alcohol affects dementia risk?
Research consistently shows that those who drink moderate amounts of alcohol have the lowest risk of developing dementia. Those who don’t drink any alcohol at all have a slightly higher risk. Those who drink excessively have the highest risk.
A recent review of the research found that drinkers had, on average, around half the risk of developing dementia compared to non-drinkers (Anstey KJ, et al. Alcohol consumption as a risk factor for dementia and cognitive decline: a meta-analysis of prospective studies. Am J Geriatr Psychiatry, 2009, 17:542-555).
This is not enough reason for non-drinkers to take up alcohol however. There are many other factors that affect dementia risk so alcohol only plays a small role. Also, alcohol drinking can cause health problems for some people.
Other research has found that excessive drinking over many years, or regular episodes of binge drinking, are associated with an increased risk of developing dementia. Long-term excessive alcohol consumption can cause brain damage and lead to a condition called alcohol-related dementia. It may also increase the risk of Alzheimer’s disease and other dementias.
Many observational studies have shown that those who drink alcohol moderately have lower dementia risk compared to those who don’t drink. The association has also been established in meta-analyses combining results from several studies.
However, the type and amount of alcohol that has the most benefit has not been determined.
The stars here are red because, most importantly, alcohol consumption carries risks for people with many medical conditions if too much is consumed, and is not recommended for dementia risk reduction.
How does alcohol affect the brain and dementia risk?
We don’t know exactly how alcohol acts to reduce the risk of dementia, but we do know it seems to have beneficial effects on the vascular system. It is likely that these lead to positive effects on the heart and the brain. Moderate alcohol consumption may exert its protective effects by:
- increasing ‘good’ (HDL) cholesterol
- lowering cardiovascular risk
- increasing brain blood flow
- relaxing blood vessels
- reducing inflammation
How much alcohol is safe?
Alzheimer’s Australia recommends that you follow the Australian Guidelines to Reduce Health Risks from Drinking Alcohol. These recommend that healthy men and women consume no more than two standard drinks on any day to reduce the lifetime risk of harm. Every drink above this level increases the lifetime risk of disease.
When considering how much alcohol is safe for you, it is important to remember that drinking can have adverse outcomes for people with certain medical conditions or on certain medications. If in doubt, talk to your doctor.
Your General Practitioner can provide advice about how much alcohol is safe for you. They can also assist you to reduce your drinking if you are consuming too much. They can write you a low-risk drinking prescription with an individual plan to help you reduce your drinking, prescribe medications or refer you to specialist help if needed.
What is a standard drink?
A standard drink contains 10 grams of alcohol. The amount of alcohol in different drinks varies, so one glass, can, stubbie or bottle is not always equal to one standard drink.
On average, one standard drink is equal to:
- a pot (285 ml) of full strength beer
- a pint (425 ml) of light beer
- 100 ml of wine
- 60 ml of port or sherry
- 30 ml (1 shot) of spirits
Check the label of your bottle, can or cask. It will state how many standard drinks are in the container.
Be especially careful with wine. When you get a glass of wine in a bar or restaurant, or pour it yourself, it is often more than 100 ml. A typical glass of wine can be 1½ or 2 standard drinks.
Further information about alcohol
An Australian Government website provides information about alcohol-related health issues and Australian Government policy.
The Australian Drug Foundation website also provides information about alcohol and its effects.