When You Have High Cholesterol, This Is What Happens To Your Brain

When you think about cholesterol, an image of steak, heavy cream, or butter might come to mind. You might also imagine the saturated fats from these foods blocking blood from flowing through your arteries. Your body needs cholesterol to function. Cholesterol helps keep the structure of our cells together and is a key ingredient in helping the body make hormones.

Your brain also needs cholesterol to properly signal brain activity, and 20% of the cholesterol in your body is in your brain (per Psychology Today). Your liver makes all the cholesterol it needs, but the saturated fat from animal foods can increase the cholesterol levels in your blood. That's when you could encounter problems with heart disease.

Just as too much cholesterol in your blood can clog up your arteries, you might assume that too much cholesterol could somehow clog up your brain as well. High cholesterol could impact the flow of blood to your brain if the arteries that supply the brain with blood become clogged. According to the Alzheimer's Society, the cholesterol from your blood doesn't enter your brain. Like your liver, your brain also makes its own cholesterol. Even though people with high cholesterol might develop dementia, they might also have other risk factors for dementia, such as high blood pressure, obesity, or diabetes. In fact, high cholesterol might have somewhat of a protective effect on the brain in the late stages of life.

Cholesterol, blood flow in the brain, and dementia risk

A 2020 study in Alzheimer's and Dementia studied the relationship between brain function and low-density lipoprotein (LDL), also known as "bad" cholesterol. The study used 10 neuropsychological tests to compare the brain function of people aged 65 to 80 who weren't taking statins to lower their LDL cholesterol. Those with higher LDL cholesterol had higher cerebral blood flow, lower cerebrovascular resistance, and improved cognitive performance. With that said, the researchers stressed that further research is needed in this area.

While that might seem surprising, a 2023 study in Neurology examined how cholesterol levels might affect the risk of dementia. More than 180,000 people who didn't have a history of dementia were monitored for almost 20 years. The people who had extremely high levels of high-density lipoprotein (HDL) cholesterol had a small but increased risk of dementia. LDL cholesterol levels weren't linked to dementia risk, but those who took statins and had high LDL cholesterol had a higher risk of Alzheimer's than those who didn't take statins.

Statins, cholesterol, and the brain

Many people take statins to reduce their cholesterol and reduce their risk of heart disease. However, this can affect your brain's ability to make the cholesterol it needs because these statins cross the blood-brain barrier, according to Psychology Today. While this might give you pause about taking statins for high cholesterol, a 2018 meta-analysis in Scientific Reports found that taking statins can reduce your risk for all-cause dementia, Alzheimer's disease, and mild cognitive impairment.

You can lower your cholesterol without medication by dumping foods high in saturated fats and adding foods high in fiber. Quitting smoking and getting at least 150 minutes of exercise can help keep your cholesterol levels in a healthy range. Per the Centers for Disease Control and Prevention, getting your cholesterol checked at least every five years is a good idea, but you might need to be screened every year if you have family members with high cholesterol. Even though a healthy lifestyle can help reduce your cholesterol, people with cardiovascular disease and diabetes should consider using medications to avoid heart disease and stroke.