High Cholesterol Affects Memory And Cognitive Function
The findings from the study suggest that for individuals who carry the ApoE4 genetic risk factor for Alzheimers disease, cognitive decline may be reduced by lowering cholesteroleven more so if they have cardiovascular disease.
ApoE4 is a protein that plays a role in the metabolizing of blood lipids. It transfers cholesterol to nerve cells, among other functions. There are three different variants of ApoE4 that can increase the risk of Alzheimers disease.
The researchers used blood samples and medical data from two alternative studies of older adults who took cognitive and memory tests. The two studies included the ESTHER study of 1,434 individuals and the KAROLA study of 366 participants. Participants with lower cholesterol performed better on cognitive and memory tests compared to those with higher cholesterol.
The findings suggest that to maintain memory and cognitive function, taking necessary measures to lower cholesterol and prevent cardiovascular disease is crucial.
Cholesterol Variation And Cognitive Decline In All Participants
After multivariate adjustment, the risk of global cognitive decline for the lowhigh TC group was borderline significant compared with the lowlow TC group. The risk of memory function decline for the highlow TC group was significantly increased compared with the highhigh TC group. The OR and 95% CI of global cognitive decline and memory function decline for the lowhigh NHDL-C group were 0.50 and 0.45 , respectively, with the lowlow NHDL-C group as the reference. Cognitive decline was not remarkably associated with LDL-C and HDL-C variation in all participants after adjusted covariates . In the first and second statistical models, the association of LDL-C and NHDL-C with cognitive decline was in line with that in the third model. However, the TC variation was not significantly associated with cognitive decline. The persistent high level of HDL-C was positively and significantly associated with global cognitive decline and memory function decline in the first model .
Whats The Difference Between Mild Cognitive Impairment And Decline Due To Normal Aging
Some gradual mental decline is seen with normal aging. For example, the ability to learn new information may be reduced, mental processing slows, speed of performance slows, and ability to become distracted increases. However, these declines due to normal aging do not affect overall functioning or ability to perform activities of daily living. Normal aging does not affect recognition, intelligence, or long-term memory.
In normal aging, a person may occasionally forget names and words and misplace things. With mild cognitive impairment, the person frequently forgets conversations and information that one would ordinarily remember such as appointments and other planned events.
You May Like: Do Ritz Crackers Have Fiber
What To Feed Your Brain
Low-fat diets are not good for your brain. Focus on healthy fats, such as avocados, nuts, seeds, and sustainable, clean fish. Fat is not the enemy. Good dietary fats are essential to your brain health. For example, omega-3 fatty acids have been found to reduce symptoms of depression.
In a study from the Mayo Clinic, people who ate a fat-based diet had a 42% lower risk of developing Alzheimers disease those who ate a protein-based diet had a 21% percent lower risk of developing Alzheimers but those who ate a simple carbohydrate-based diet had a 400% percent increased risk of developing Alzheimers. Its the sugar, and foods that turn to sugar, not the fat, thats the problem.
However, not all fats are equal. Avoid trans fats , which are associated with an increase in depression. Also skip fats that are higher in omega-6 fatty acids, such as many refined vegetable oils, which are associated with an increase in inflammation, which also has negative effects on brain health.
Memory problems, brain fog, depression, and other mental and cognitive health issues cant wait. During these uncertain times, your mental well-being is more important than ever and waiting until life gets back to normal is likely to make your symptoms worsen over time.
Boost Your Memory By Eating Right
How diet can helpor harmyour cognitive fitness.
Before you cut into a big T-bone steak with French fries, here is some food for thought: Research suggests that what we eat might have an impact on our ability to remember and our likelihood of developing dementia as we age.
Take that steak you’re about to slice into, for example. It’s loaded with saturated fat, which is known to raise blood levels of unhealthy low-density lipoprotein cholesterol. Other kinds of fats, such as trans fats, do the same thing to LDL.
LDL cholesterol builds up in, and damages, arteries. “We know that’s bad for your heart. There is now a lot of evidence that it’s also bad for your brain,” says Dr. Francine Grodstein, associate professor of medicine at Harvard Medical School and associate epidemiologist at Brigham and Women’s Hospital.
|
Beta-amyloid plaque in the brain Diets high in cholesterol and fat might speed up the formation of beta-amyloid plaques in the brain. These sticky protein clusters are blamed for much of the damage that occurs in the brains of people with Alzheimer’s. |
Recommended Reading: How Long Should You Wait Between Cholesterol Tests
What You Can Do About Cholesterol And Your Memory
While researchers continue to piece together the puzzle of cholesterol and memory loss, there’s a lot of action you can take now if you’re concerned about your cholesterol levels.
According to the American Heart Association, getting regular exercise and avoiding tobacco smoke can help to moderate cholesterol levels. Cholesterol-lowering drugs can also help you achieve your cholesterol goals.
And eating a heart-healthy diet is strongly recommended. In addition to avoiding saturated fats and cholesterol, Dr. Connor and other experts encourage people to get plenty of fiber, eat fruits and vegetables regularly , and have one or two servings of fish per week.
The Link Between Statins Memory Loss & Dementia
Last updated July 23, 2021.Edited and medically reviewed by Patrick Alban, DC. Written by Deane Alban.
Memory loss and dementia are some of many side effects of statins. Learn what to do if you think statins are causing memory loss for you.
If youve been diagnosed with high cholesterol, its very likely that your doctor prescribed a type of cholesterol-lowering drug called a statin.
Statins, also known as HMG-CoA reductase inhibitors, are the most commonly prescribed drugs in the world and among the most profitable.
Annual worldwide sales were forecasted to reach one trillion dollars by 2020.
Over one in five Americans between the ages of 40 and 75 takes these drugs ostensibly to prevent a heart attack or stroke.
The US is currently experiencing epidemics of memory loss, dementia, and Alzheimers disease .
This may not be a coincidence.
Is there a connection between taking statins and the rise in memory loss and dementia?
Also Check: Tuna High In Cholesterol
Whats The Outcome For People With Mild Cognitive Impairment
Researchers believe that most patients with mild cognitive impairment will go on to develop dementia. MCI is a stage between the mental decline seen in normal aging and the onset of early dementia.
It is not yet possible to know the rate of decline in a particular person with mild cognitive impairment. Researchers continue to study the mental and medical changes that occur in patients with mild cognitive impairment in the hopes of better predicting who might be at an increased risk of developing and the speed at which they develop — specific types of dementia.
Last reviewed by a Cleveland Clinic medical professional on 03/18/2019.
References
What Are The Symptoms Of Mild Cognitive Impairment
Examples of memory and thinking problems that might be seen in someone with mild cognitive impairment include:
- Memory loss. Forgets recent events, repeats the same questions and the same stories, forgets the names of close friends and family members, forgets appointments or planned events, forgets conversations, misplaces items often.
- Language problems. Has trouble coming up with the desired words. Has difficulty understanding written or verbal information.
- Attention. Loses focus. Is easily distracted.
- Reasoning and judgment. Struggles with planning and problem solving. Has a hard time making decisions.
- Complex decision-making. May struggle, but can complete complex tasks such as paying bills, taking medications, shopping, cooking, household cleaning, driving.
You May Like: Shrimp And Triglycerides
Studies Find Low Hdl Or High Ldl Raises Memory Loss Risk
Research shows that there may be a link between cholesterol levels and memory loss. But the impact of lowering cholesterol levels is not consistent.
- A study, published in July 2008 in Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association, found that, by the age of 60, men and women with low levels of HDL were 53 percent more likely to have memory loss than those with higher levels. The use of statin drugs to raise HDL levels or to lower levels of LDL was not found to have any association with memory loss in the study.
- And this isn’t the first time researchers have found a link between cholesterol and memory problems. An earlier study in 2002, published in the Archives of Neurology, found that women with high levels of LDL had increased degrees of cognitive impairment, including memory loss. Four years later, study subjects who lowered their LDL levels also lowered their chances of suffering from cognitive impairment.
- In 2004, a study from the Netherlands found that a diet high in cholesterol and saturated fat was linked to an increased risk of cognitive decline among middle-aged study subjects. That study, published in the journal Neurology, also concluded that consumption of fish and fish oil was associated with a lower risk of cognitive decline the reputation of fish as “brain food” appears to be intact.
Sv And Signaling Pathways In Wm
Our findings of elevated pMAPK expression in the RMS of the SVZ in HCD-fed TGF mice concurrently treated with SV support a role for MAPK/ERK signaling in oligodendrocyte proliferation, migration, and maturation and, hence, remyelination. Sustained activation of ERK1/2 was found sufficient to drive adult oligodendrogenesis, contribute to remyelination and enhance hippocampal-based behavior. Other studies indicated that ERK signaling can reactivate quiescent mature oligodendrocytes to reinitiate myelination. Our findings with SV thus support a role for MAPK/ERK pathway in myelin repair and, possibly, cognitive recovery. Cross-talk with other pathways, like the Wnt/-catenin and Akt/mTOR pathways, however, seems likely,.
Read Also: Does Canned Tuna Have Cholesterol
Cholesterol Variation And Cognitive Decline In Participants With Or Without Cardiovascular Disease
In participants without cardiovascular disease, remarkably lower risk of global cognitive decline and memory function decline were observed in the lowhigh NHDL-C group with the lowlow group as the reference in the multivariate adjustment model, but global cognitive decline was not remarkably associated with TC variation. The associations of cholesterol variation with any cognitive decline were not substantial in participants with at least one cardiovascular disease . Similar results were also observed in the first statistical model for LDL-C and NHDL-C and cognitive decline. In addition, we observed a considerable increase in the ORs of global cognitive decline and memory function decline in the highhigh HDL-C group with the lowlow group as a reference in participants without any cardiovascular disease although it was not significant in the adjusted model .
Figure 5. Association between cholesterol variation and cognitive decline in participants with or without cardiovascular disease. ¶Take the lowlow group as a reference §Take the highhigh group as a reference. Baseline age, education, marital status, smoking, drinking, BMI, exercise, diabetes, history of disability, medication use , and the number of comorbidities were adjusted. TC, total cholesterol NHDL-C, non-high-density lipoprotein cholesterol LDL-C, low-density lipoprotein cholesterol HDL-C, high-density lipoprotein cholesterol OR, odds ratio CI, confidence interval.
What Is Mild Cognitive Impairment
Mild cognitive impairment is a condition in which a person experiences a slight but noticeable decline in mental abilities compared with others of the same age. The minor decline in abilities is noticeable by the person experiencing them or by others who interact with the person, but the changes are not severe enough to interfere with normal daily life and activities.
Don’t Miss: Oyster High In Cholesterol
Lipoprotein Secretion And Metabolism In The Brain
The mechanism underlying the formation of nascent lipoproteins in the brain is not completely understood. Among glial cells, astrocytes are responsible for the synthesis of the majority of lipoproteins found in brain tissue and CSF . Cultured astrocytes synthesize discoidal lipoproteins containing phospholipids, unesterified cholesterol, and apoE or apoJ.
Several ATP-binding cassette transporters, which are transmembrane proteins that utilize ATP hydrolysis to fuel transport of a variety of substances across biological membranes, are expressed in the CNS and are involved in apoE-containing lipoprotein secretion and lipidation . ABCA1 is expressed ubiquitously and interacts with lipid-free or poorly-lipidated apoE. ABCA1 in astrocytes is responsible for the secretion of newly lipidated nascent discoidal HDL-like particles. ABCA1 may also play a critical role in the removal of excess cholesterol from neurons, as shown in vitro using spherical reconstituted apoE-containing particles, as well as in microglia. A further incorporation of cholesterol into lipoproteins may be mediated by ABCG1 and ABCG4. ABCG1 in the CNS is expressed in microglia, oligodendrocytes, neurons, and astrocytes, whereas ABCG4 seems to be expressed preferentially in neurons. ABCA8 is expressed in several regions of the adult human brain with significantly higher expression in oligodendrocyte-enriched white matter compared with grey matter.
What Causes Mild Cognitive Impairment
All possible causes of mild cognitive impairment have not been completely discovered. In a small number of cases, another condition may be causing the symptoms seen in mild cognitive impairment. Some of the possible conditions include:
- Depression, stress, and anxiety
- Diseases or conditions that affect blood flow in the brain
- Low vitamin B12 levels or other nutrient levels
- Eye or hearing problems
- An infection
- Side effects of certain prescription or illegal drugs
- History of alcoholism
Many of these causes of mild cognitive impairment are treatable.
Most cases of MCI, however, are due to a variety of diseases, such as Alzheimers or Parkinsons disease.
Read Also: Are Noodles Bad For Cholesterol
The Effects Of Cholesterol On Learning And Memory
Cholesterol is ubiquitous in the central nervous system and vital to normal brain function including signaling, synaptic plasticity, and learning and memory. Cholesterol is so important to brain function that it is generated independently of cholesterol metabolism in the rest of the body and is sequestered from the body by the blood brain barrier . A large number of studies pioneered by Dietschy and Turley among others have confirmed that systemic cholesterol levels do not influence cholesterol in the CNS . Given the importance of cholesterol to normal brain function, the current review will focus on the role of cholesterol in one of the most important functions of the brain learning and memory.
Chronic Pravastatin But Not Atorvastatin Treatment Impairs Cognitive Function In Two Rodent Models Of Learning And Memory
-
Affiliation School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
-
Affiliation School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
-
Affiliation School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
-
Affiliation School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
You May Like: Normal Ldl Levels Female
Cholesterol In The Brain
Similar to the liver, the brain produces cholesterol for itself. In fact, the brain has the highest cholesterol content of any organ in the body. Most of the brains cholesterol exists in the axons of nerve cells, where it protects cells and facilitates quick transmission of the electrical impulses. This has a big impact on how thought, movement, and sensation are controlled.
The reason the brain creates its own cholesterol is thatcholesterol in the blood does not cross the blood-brain barrier, meaning that braincholesterol is used and recycled in the brain. There is one problem here,however. Some versions of cholesterol lowering drugs, commonly referred to asstatins, can cross the blood brain barrier and therefore reduce the level ofcholesterol in the brain.
Scientists are still learning about the role of cholesterolin the brain, as well as the drugs they use to manipulate it and how they affectmemory, dementia and risk of stroke.
A study from the University of California, Davis Alzheimers Disease Research Center concluded that higher levels of LDL cholesterol and lower levels of HDL cholesterol were both related to having more of amyloid plaques in the brain, a signature of people suffering from Alzheimers.
But as they learn more, researchers uncover trends thatindicate previous findings are not always concrete.
Cholesterol Particle Size Matters
Unfortunately, most doctors worry more about patients cholesterol numbers than their overall health.
Testing for HDL cholesterol or LDL cholesterol levels is overly simplistic.
One test that does seem to provide good information about your risk for heart disease is to measure LDL particle size.
Large LDL molecules just move through the bloodstream, doing no harm.
But small LDL molecules are caused by oxidation and are dangerous.
Chronic inflammation promotes every known degenerative disease.
It causes microinjuries to your arteries, causing problematic plaque formation.
Free Radicals
Free radicals are unattached oxygen molecules that attack your cells in much the same way that oxygen attacks metal, causing it to rust.
They also attack LDL cholesterol transforming it from large to small LDL particles.
Stress
The stress hormone cortisol contributes to heart disease by increasing triglycerides and blood pressure, two common risk factors.
Stress also contributes to plaque deposits in the arteries.
Sugar
A 15-year study found there to be a strong correlation between sugar consumption and death from heart disease.
Sugar promotes inflammation, raises blood pressure, and stimulates the liver to dump harmful fats into the bloodstream.
Trans Fats
Trans fats are unhealthy fats found in processed foods.
They increase bad cholesterol, decrease good cholesterol, increase inflammation, and raise triglyceride levels.
Recommended Reading: Does Shrimp Have Good Cholesterol Or Bad Cholesterol
Solving The Mystery Of Cholesterol And Memory Loss
How does cholesterol affect memory and cognitive function? The precise answer to that question remains a mystery. Researchers speculate that HDL may improve memory in a number of ways. HDL has anti-inflammatory and antioxidant properties, which may improve brain function. HDL may also prevent the formation of beta-amyloid that forms in the brain tissue of Alzheimer’s patients.
A review of studies in 2011 noted that “cholesterol seems to be intimately linked with the generation of amyloid, ” which develops in Alzheimer’s disease. The majority of the studies they looked at found an association between cholesterol and Alzheimer’s disease.
William Connor, M.D., professor of medicine at Oregon Health and Science University in Portland, Oregon, says that cholesterol affects brain functioning primarily through the link between LDL and strokes, which are caused by atherosclerotic plaque formation in the blood vessels of the brain.
“High cholesterol levels in the blood can predispose the deposition of plaque in the blood vessels,” says Connor, a specialist in atherosclerosis . And, he adds, “stroke can result in memory loss.”
And a more recent study, published in 2021 found that participants with high triglyceride levels and low HDL levels showed decreased integrity of the hippocampus, which is an area of the brain that is involved in memoryand this area often shows signs of amyloid buildup and atrophy in people who have dementia.