What is the link between alcohol and Alzheimer’s disease?
Excessive alcohol use may put a person at risk of developing certain health problems relating to the brain. This may increase the likelihood of developing Alzheimer’s disease.
Around one in six American adults drink to excess, and almost half of the United States population drank alcohol in 2020. Excessive drinking can cause long-term effects such as stroke, heart disease, and cancer.
Long-term alcohol use may lead to Alzheimer’s disease (AD), a type of dementia that affects more than six million Americans. And although the likelihood of having dementia also increases with age, it is not a typical part of aging.
This article discusses the link between moderate and excessive alcohol consumption and AD and the risks of other conditions.
A note about sex and gender
Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.
Moderate drinking and AD
A 2020 study showed that moderate alcohol intake could lower a person’s risk of developing Alzheimer’s disease.
The study defined moderate drinking as consuming 1–13 standard drinks per week, equivalent to 10–130 grams (g) per week.
However, drinking guidelines do vary per country. A standard drink contains 14 grams, or 0.6 ounces (oz), of pure alcohol in the United States.
Generally, this is equivalent to:
- 12 oz of beer with 5% alcohol: approximately one beer
- 5 oz of wine with 12% alcohol: one standard glass of wine
- 8 oz of malt liquor with 7% alcohol: one standard glass of malt liquor
- 1.5 oz of liquor or distilled spirits with 40% alcohol: a standard shot glass of spirit
A 2019 review found a significant association between reducing a person’s alcohol consumption with a lower risk of cognitive impairments and dementia.
Drinking in moderation
According to the Dietary Guidelines for Americans 2020–2025, drinking in moderation consists of no more than one or two drinks daily for females and males, respectively.
Aside from moderate drinking, adopting healthier lifestyle choices may help reduce the risk of long-term health issues such as AD. These lifestyle choices include:
- performing moderate physical activity
- following balanced diet
- avoiding tobacco
A person can consult a doctor for further guidance in following a healthy diet, quitting smoking, or suitable exercise programs.
Effects of excessive alcohol consumption
The National Institute on Alcohol Abuse and Alcoholism defines excessive drinking as consuming more than 4 drinks on any day or more than 14 drinks per week for males. For females, it involves consuming more than 3 drinks on any day or more than 7 drinks per week.
Research considers alcohol neurotoxic, meaning it damages the brain. It can reduce the size of the hippocampus, the area of the brain responsible for learning and memory.
Over time, excessive alcohol consumption increases a person’s risk of AD by 300%.
A 2019 review also found that excessive alcohol consumption and alcohol use disorder puts a person at a higher risk of all types of dementia. This review also associates excessive alcohol consumption with tobacco smoking and depression, increasing the risk.
Other factors that have links to the development of dementia may include infections, such as HIV or neurosyphilis, or thyroid disorders.
Alcohol in excess can also lead to a deficiency in thiamin, or vitamin B1. This deficiency may also cause conditions that damage the brain, including:
- Wernicke-Korsakoff syndrome
- hepatic encephalopathy
- head injury or trauma
- vascular dementia
Learn more about Alzheimer’s and dementia from our dedicated hub.
Alcohol-related dementia vs. Wernicke-Korsakoff syndrome
Alcohol-related dementia and Wernicke-Korsakoff syndrome may develop due to regular excessive alcohol consumption over many years.
Excessive alcohol may compromise executive functions in people with dementia and can lead to memory, learning, problem-solving, and judgment problems. Individuals may also be irritable, have sudden outbursts, and have issues with coordination and balance.
A vitamin B1 deficiency resulting from excessive alcohol consumption may also cause Wernicke-Korsakoff syndrome, rather than the disorder being a direct result of alcohol misuse.
Wernicke’s encephalopathy and Korsakoff’s syndrome are both due to brain damage from a lack of thiamine. They cause various symptoms to develop in a person, which affects both physical and mental functions.
Symptoms of Wernicke encephalopathy include:
- nystagmus, or involuntary eye movement
- vision issues
- drooping eyelid
- an impaired ability to walk
- loss of coordination and balance
Symptoms of Korsakoff syndrome include:
- a loss of memory and inability to form new memories
- making up stories to fill gaps in memory, which doctors call confabulation
A person should consult a doctor if they are experiencing any of these symptoms to receive a prompt diagnosis.
Other health conditions
Chronic alcohol use may also link to other health conditions, including:
- high blood pressure
- atrial fibrillation
- ischemic heart disease
Other causes of dementia
Changes to brain cells often cause dementia. These changes may hinder the brain from functioning properly, causing cognitive decline.
Medical professionals associate many types of dementia with brain cell damage. Alzheimer’s disease, the most common type of dementia, results from an atypical protein buildup in the brain.
Lewy body dementia is another progressive type of dementia that causes an accumulation of proteins called Lewy bodies in various brain areas. These areas are responsible for movement, emotions, behavior, memory, and cognition.
Other conditions that cause brain or brain cell damage can also cause dementia. These include:
- Huntington’s disease
- Parkinson’s disease
- Creutzfeldt-Jakob disease
- traumatic brain injury
- brain tumor
What are the effects of alcohol while having AD?
Alcohol may increase confusion in a person with AD.
Moreover, it can also interact with certain medications. Drinking alcohol with Aricept (donepezil), a medication for certain types of dementia, can prevent it from working properly and increase the risk of side effects.
A 2016 study found that heavy drinking, equating to eight or more drinks per week, and drinking liquor increased cognitive decline among people with AD.
Long-term, excessive alcohol use can cause permanent damage to the brain, which can lead to Alzheimer’s and other types of dementia.
A person may consider joining support groups or attending counseling or therapy if alcohol use is impairing their quality of life in the short and long term.
They may also require medications to help manage symptoms and conditions due to excessive alcohol use.
Many studies support the strong link between alcohol use and Alzheimer’s disease.
While light or moderate drinking may protect against the development of Alzheimer’s disease, chronic alcohol use over an extended period can cause irreversible brain damage. This excessive consumption puts a person at risk of various brain diseases, including AD, stroke, and heart disease.