There is a strong association between high cholesterol levels and the risk of different types of dementia, including vascular dementia, Alzheimer’s disease, and other types of dementia.

Cholesterol is a substance naturally produced by your liver that can also be found in certain foods such as red meat or butter. The two types of cholesterol that are most prevalent in the body are high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol.

HDL cholesterol, also known as the “good” cholesterol, helps remove fats and unhealthy forms of cholesterol from the body.

LDL, or the “bad” cholesterol, is also important for the body’s functioning, but when it accumulates, it can build up on arteries, form plaque, and increase your risk of conditions such as stroke and heart attack.

Dementia is memory loss and loss of other thinking abilities. There are several different types of dementia, and the most common are Alzheimer’s disease and vascular dementia.

Additionally, chronic alcohol use, head trauma, and liver disease are other common causes of dementia. Many people also have combined dementia — where they develop more than one type of dementia, with a more rapid or more severe decline in thinking skills and self-care.

This article explores whether research has found an association between high cholesterol levels and the onset of dementia.

Vascular dementia is caused by cardiovascular disease, and it’s well known that high cholesterol levels are a major factor in vascular dementia. Studies are also finding a strong link between high cholesterol and Alzheimer’s disease, as well as other types of dementia.

Researchers have several explanations for these links. High cholesterol causes oxidative damage, which can worsen degeneration in the brain associated with Alzheimer’s disease, alcohol use, liver disease, and head trauma.

Also, high cholesterol causes vascular dementia, compounding the symptoms of other types of dementia. Some of these studies specify one or more types of dementia, and some studies combine all of them in their outcomes, often calling it “all cause” dementia.

Studies

A long-term 2021 study followed a cohort of people 40 years and older and focused on LDL cholesterol and its effects. The researchers found a modest association between high LDL cholesterol measured in mid-life and the risk of dementia 10 years later. They also believed LDL cholesterol should be added as a modifiable risk factor for dementia.

Another long-term 2023 study looked into both HDL and LDL cholesterol levels and possible links to dementia and concluded that both high and low levels of HDL were associated with an increased risk of dementia, while LDL levels only presented a modest increase in risk.

This 2020 review of studies strengthened previous findings by analyzing 100 primary studies and reviews of studies and concluding that LDL cholesterol was a significant risk factor for the development of Alzheimer’s disease.

The researchers also highlighted the importance of more studies on this topic to find out whether physical activity and medication could influence the effect of cholesterol on Alzheimer’s disease.

Conversely, this 2023 study concluded that a high intake of dietary cholesterol was associated with a decreased risk of all-cause dementia, including Alzheimer’s disease. However, the researchers acknowledge the need for more studies to verify or refute these findings.

Other studies have come up with different results. A 2021 review of studies concluded that there was no clear relationship between cholesterol and dementia in the older adult group, and that this effect was not changed by statin use (medications that lower cholesterol).

The most recent 2024 study found an association between HDL cholesterol and an increased risk of all-cause dementia in middle-aged people as well as other individuals, rather than LDL cholesterol, as had been the case in previous studies. The association appeared to be strongest in people ages 75 years and older.

Most studies have found a strong link between LDL and HDL cholesterol and an increased risk of dementia, with only one review of studies indicating no clear relationship.

More research is necessary still to determine how cholesterol screening or treatment might play a role in managing or preventing dementia.

Multiple factors are associated with an increased risk of high cholesterol. You can change some of them through lifestyle modifications, but some of them can also be genetic.

Factors that can increase your risk of having high cholesterol:

High cholesterol can run in families, so having a close family member, like a parent or a sibling, who has it can make it more likely for you to have it as well. High cholesterol doesn’t typically cause any symptoms, so it’s very important to get tested.

A blood test should be enough to diagnose high cholesterol levels, and certain medications, such as statins, are available for treatment if lifestyle strategies have not been sufficient.

The most prevalent types of cholesterol in the body are HDL and LDL. Both are vital for the body’s functioning but LDL can build up in the body and block arteries, leading to conditions such as stroke or heart attack. These conditions can be life threatening.

Several degenerative conditions can cause dementia and lead to progressive memory loss and loss of thinking abilities. Alzheimer’s disease is the most common type.

Research has identified a link between high LDL cholesterol levels and the development of different causes of dementia, including Alzheimer’s disease. Other studies have also highlighted a possible link between high HDL cholesterol levels and an increased risk of dementia.

High cholesterol is a known risk factor for vascular dementia, and it’s also linked with other types of dementia. The specific mechanism by which cholesterol can cause dementia needs to be established so that screening methods and treatment can be improved.