You can’t change your age or your genetics, but by staying physically, mentally, and socially active, you may be able to reduce your risk of dementia. Other lifestyle habits may also help.
Dementia is a decrease in mental ability that affects your everyday functioning. Common symptoms include:
memory loss
difficulty thinking
difficulty communicating
difficulty with coordination and movement
general confusion and disorientation
Several factors can affect your risk of developing dementia. Some factors, such as whether you smoke, are within your control. Others, such as your genetics, are not.
It’s important to understand that a risk factor is not a cause. For example, diabetes is a risk factor for both Alzheimer’s disease and vascular dementia, but that does not mean it causes either of those conditions. Not all people with diabetes develop dementia.
How dementia risk increases with age
The most significant risk factor for Alzheimer’s disease, vascular dementia, and several other types of dementia is increasing age. According to 2024 data from the Alzheimer’s Association, about 1 in 9 people ages 65 and older — or about 6.9 million people — in the United States have Alzheimer’s.
Canada’s Alzheimer’s Society notes that the risk of dementia doubles every 5 years after age 65.
But dementia is not inevitable with advanced age. While a certain amount of mental decline is natural as you age, you may be able to delay that process and reduce your dementia risk by maintaining healthy lifestyle habits, especially physical activity.
Social isolation and dementia risk
The World Health Organization notes that social isolation is a risk factor for dementia. A long-term study published in 2019 suggests that social contact with others can help protect against dementia. And some observational studies note that social participation in middle and late adulthood can reduce dementia risk by 30% to 50%.
Recent research notes that these findings are especially important in the aftermath of the COVID-19 pandemic and the physical distancing measures that separated many people.
Researchers also suggest that some groups of people may be at greater risk of social isolation, including those who live in poverty and those who belong to traditionally marginalized groups, such as LGBTQ+ older adults.
Mental activity and dementia risk
We’ve mentioned that staying physically active can help reduce your risk of dementia. But keeping your mind active is just as important.
To slow down mental decline, experts recommend regularly engaging in activities that stimulate your brain, such as:
reading
crafting
completing games and puzzles
using a computer
Hearing loss and dementia risk
In addition to experiencing a decline in thinking ability with age, many people also lose their hearing as they age. But the link between the two conditions may be much deeper.
Though experts are still unsure of an exact link, age-related hearing loss may contribute to both social isolation and decreased mental activity.
Older adults can manage this risk factor by using hearing aids, as evidenced in a 2023 study. You can talk with a doctor or audiologist who can conduct tests and fit you for hearing aids.
Smoking and dementia risk
Smoking is an established risk factor for dementia — particularly vascular dementia. If you smoke, you have a higher risk of atherosclerosis (narrowing of your arteries) and other types of vascular disease (diseases that affect your blood vessels). These diseases may contribute to an increased risk of dementia.
A large 2023 study in Korea suggests that reducing the amount you smoke may not be enough to reduce your dementia risk. The researchers found that only quitting helped reduce the risk of dementia.
Alcohol use and dementia risk
According to a 2024 research review, there is a link between excessive alcohol consumption and an increased risk of dementia — but not all types of dementia. Specifically, it can increase your risk of Wernicke-Korsakoff syndrome (WKS). Symptoms of WKS include:
confusion
apathy
agitation
alogia (speaking less often and with fewer words)
hallucinations
confabulation
If you have alcohol use disorder, seeking help from a healthcare professional may reduce your risk of developing WKS or other dementias in the future.
Air pollution and dementia risk
Increasing international evidence suggests that air pollution may raise the risk of dementia. Researchers think that inhaling pollutants, especially fine particulate matter, can trigger inflammatory responses that contribute to a decline in thinking ability.
The Environmental Protection Agency recommends checking your local Air Quality Index to find out when outdoor air pollution may be at harmful levels.
Medical conditions that increase dementia risk
Certain medical conditions may increase your risk of developing dementia. In some cases, you can manage these conditions to reduce your risk. Examples include:
Atherosclerosis: Plaque can build up on your artery walls, narrowing your arteries and interfering with blood flow to your brain. This impairs your brain cells’ ability to function properly, ultimately leading to the death of brain cells and the loss of their connections to other brain cells (vascular dementia).
Diabetes: High blood sugar from diabetes can cause inflammation, which can lead to brain cell damage. People with both type 1 and type 2Trusted Source diabetes are at increased risk of developing Alzheimer’s and vascular dementia.
High cholesterol: A high LDL cholesterol level can lead to atherosclerosis, which increases your risk of vascular dementia.
High homocysteine: This amino acid naturally circulates in your blood and is a building block of protein. Too much homocysteine may suggest a deficiency of vitamin B6, vitamin B12, or folate. Research suggests this is a risk factor for Alzheimer’s and vascular dementia.
High blood pressure: Researchers have proposed many ways that high blood pressure (hypertension) may increase dementia risk. Hypertension in midlife (ages 40 to 64) is of particular risk.
In the case of some other medical conditions that can lead to dementia, there is not much you can do to change the level of risk. Examples include:
Amyotrophic lateral sclerosis (ALS): Many people with ALS also develop frontotemporal dementia. Experts believe this is due to a genetic link between the two conditions.
Down syndrome: By middle age, most people with Down syndrome have the plaques and tangles that are hallmarks of Alzheimer’s disease.
Huntington’s disease: People with this rare genetic condition lose brain cells in a specific part of the brain, which leads to dementia.
Parkinson’s disease: Most people with Parkinson’s disease develop protein clumps called Lewy bodies inside some brain cells. This leads to a decline in thinking ability and, eventually, dementia.
Mild cognitive impairment and dementia risk
You can think of mild cognitive impairment (MCI) as a stage between typical forgetfulness and dementia. If you have MCI, it does not always mean you’ll develop Alzheimer’s. But most cases of Alzheimer’s start with MCI.
Symptoms of MCI include:
memory loss greater than expected for your age
memory loss that’s significant enough to be noticed and measured
continued independence because the deficiency is not enough to compromise your ability to care of yourself and conduct regular activities
How genetics influences dementia risk
Many forms of dementia have a genetic component, and it often runs in families. Scientists have identified several specific gene mutations linked to certain types of dementia, including:
APP, PSEN1, and PSEN2Trusted Source in Alzheimer’s
APOE-E4 and GBA in dementia with Lewy bodies
C9orf72 in frontotemporal dementia
Some genetic conditions, such as Huntington’s disease, may also lead to dementia.
While you cannot change your genetics, you may be able to undergo genetic testing to better understand your risk of dementia.
Takeaway
Many risk factors are involved in the development of dementia, including medical conditions, lifestyle habits, genetics, and old age. If you have a high risk of developing dementia, you can talk with a doctor about any lifestyle changes or other measures that may help reduce your risk.