Your doctor probably discussed so-called “bad cholesterol,” LDL (low-density lipoproteins), as it pertains to cardiovascular disease.
Next, he likely examined your “good cholesterol” HDL (high-density lipoproteins) numbers.
High levels of HDL may lower your risk of heart disease and stroke. But that’s not all…
Researchers now say that HDL could be a key player in maintaining your brain health and in turn, lowering your risk of Alzheimer’s disease.
HDL is called the good cholesterol because it’s credited with absorbing bad LDL cholesterol and carrying it back to the liver so that the liver can break it down and eliminate it from the body before it clogs blood vessels and arteries.
The Link Between HDL and Your Brain
This latest study was conducted through the University of Southern California Alzheimer’s Disease Research Center and featured 180 healthy participants aged 60 and older.
The researchers used a technique called ion mobility to measure and count the HDL particles in the participants’ blood plasma and cerebrospinal fluid. Then 141 of the 180 participants also took a series of cognitive tests.
What did the team discover?
“Individuals with greater levels of small particles in the brain did better on cognitive tests and had less amyloid plaques,” reports Dr. Hussein Yassine, the study’s lead author.
It turns out this positive effect existed regardless of the participants’ age, educational level, or even if they were carriers of the APOE4 gene, which has been linked to a higher risk of Alzheimer’s disease.
Plus, the positive results were even more pronounced in participants with no cognitive impairment.
The study was published in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.1
Study Findings May Spur New Treatments For Alzheimer’s Disease
Dr. Yassine shed some light on the implication of these findings.
He deduces that the mechanisms that promote small HDL formation in the brain could also play a role in preventing Alzheimer’s disease.
Dr. Yassine suspects these particles could serve as the brain’s housecleaners, clearing out the peptides that form amyloid plaques and thereby reducing the risk of Alzheimer’s disease progression.
“Now that we have a good target to monitor, we can find what interventions (diet, exercise, and drugs) increase brain small HDL with the hope that this will translate into protecting our brains,” he explains.
Dr. Paul Schulz, a neurologist with UTHealth Houston, who was not involved in the study, cautions that more research is warranted. However, he says the study encourages researchers to take a deeper dive into the role that HDL has on brain health.22
“This [study] tells us to stay tuned to the brain fat metabolism story,” Dr. Schulz states.
“As we discover more compounds that have a positive effect on this system, we may be able to reduce the risk of Alzheimer’s disease significantly.” While researchers broaden the scope of this study we’ll be watching. Although a larger sample size is called for, these findings are still significant.
According to Dr. Yassine this is the first-time researchers have linked the small HDL particles in the brain to better cognitive function.
"What we're finding here is that before the onset of cognitive impairment, these oils—these small HDL particles—are lubricating the system and keeping it healthy," Dr. Yassine explains.
"You've got time to intervene with exercise, drugs or whatever else to keep brain cells healthy."
My Takeaway
Genetics absolutely play a role in HDL levels, but there are a myriad of ways to increase your levels naturally by making positive lifestyle tweaks now.
Proven ways to help boost your good HDL levels and your overall brain health include regular exercise and choosing foods rich in healthy unsaturated fats, such as avocados, salmon, and olive oil.3 And it’s not a bad idea to choose purple produce, such as eggplant, red cabbage and blueberries. All of these are rich in antioxidants known to raise good HDL cholesterol levels.4
- Martinez AE, Weissberger G, Kuklenyik Z, He X, Meuret C, Parekh T, Rees JC, Parks BA, Gardner MS, King SM, Collier TS, Harrington MG, Sweeney MD, Wang X, Zlokovic BV, Joe E, Nation DA, Schneider LS, Chui HC, Barr JR, Han SD, Krauss RM, Yassine HN. The small HDL particle hypothesis of Alzheimer's disease. Alzheimers Dement. 2023 Feb;19(2):391-404. doi: 10.1002/alz.12649. Epub 2022 Apr 13. PMID: 35416404; PMCID: PMC10563117.https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/alz.12649
- McGovern Medical School Department of Neurology. Dr. Paul Schulz. https://med.uth.edu/neurology/faculty/paul-e-schulz-md/
- Medical News Today. What are the benefits of olive oil? https://www.medicalnewstoday.com/articles/266258
- >Zhu Y, Ling W, Guo H, Song F, Ye Q, Zou T, Li D, Zhang Y, Li G, Xiao Y, Liu F, Li Z, Shi Z, Yang Y. Anti-inflammatory effect of purified dietary anthocyanin in adults with hypercholesterolemia: a randomized controlled trial. Nutr Metab Cardiovasc Dis. 2013 Sep;23(9):843-9. doi: 10.1016/j.numecd.2012.06.005. Epub 2012 Aug 17. PMID: 22906565.https://pubmed.ncbi.nlm.nih.gov/22906565/