Summary: Alzheimer’s is on the rise, yet there is no known effective measure to prevent its onset. Most efforts have a limited role in preventing its progress, too. Even worse, there are no reliable early biomarkers of the condition. Omega-3 fatty acids are known to be good for brain health. Data from a new study suggests that it may help slow down Alzheimer-related cognitive decline. However, prolonged use of omega-3 does not appear to lower the level of cerebrospinal fluid biomarkers.
Keywords: Omega-3 fatty acids, Alzheimer’s, Alzheimer’s prevention, Alzheimer’s related memory decline
The prevalence of Alzheimer’s is growing globally. And yet, researchers have very little knowledge of the condition. It is known that Alzheimer’s starts several years, or perhaps decades before its diagnosis. However, there are no early biomarkers or lab tests that could help confidently predict the risk of Alzheimer’s later in life.
Like many non-infectious diseases, its rise is considerably linked to an altered lifestyle. Afterall, the genetic make of humans has not changed significantly in the last century or so. Thus, researchers think that the higher prevalence of Alzheimer’s has something to do with food choices and other lifestyle factors.
Data shows that humans are not consuming fewer omega-3 fatty acids. Thus, the rise of many metabolic and non-communicable may be related to its low consumption.
In recent years, studies have started exploring the role of omega-3 fatty acids in the brain and studying the role of individual omega-3 fatty acids. For example, studies show that eicosapentaenoic acid (EPA) has a significant mood-stabilizing effect. Furthermore, since the brain is abundant in docosahexaenoic acid (DHA), it may have a more substantial role in preventing neurodegenerative diseases like Alzheimer’s or Parkinson’s. Therefore, there is also a need to understand the role of docosapentaenoic acid (DPA) in brain health1.
A new study suggests the memory stabilizing role of omega-3 fatty acids
Many studies are suggesting the beneficial effect of omega-3 supplementation on brain health. However, measuring such an impact is complicated, particularly in the absence of reliable early biomarkers of dementia.
The new study studied how 2.3 g of omega-3 a day could influence memory and spinal fluid biomarkers on its prolonged use. The study had a small sample size of 33 patients, out of which 18 received the omega-3 supplement for six months and the rest placebo. Researchers tested memory and various biomarkers in the spinal fluid at the start of the study and in the end.
Interestingly enough, the study reported some paradoxical findings. It found that omega-3 indeed improved memory function. However, it did not improve spinal fluid markers. On the contrary, omega-3 increased the levels of specific inflammatory markers that are known to worsen brain health.
The group that regularly used omega-3 supplements had much better results on the Mini-Mental State Examination (MMSE). Most biomarkers in both the omega-3 and placebo group remained unchanged. However, in the omega-3 group, there was a statistically significant rise in two inflammatory makers:neurofilament light (NfL) and chitinase-3-like protein 1 (YKL-40)2.
Such findings have several implications. First, it demonstrates that various biomarkers related tothe worsening of Alzheimer’s cannot be used to assess the benefit of the disease therapy. Moreover, they appear to be elevated a bit despite an improvement in cognition in the omega-3 group – a difficult to explain and paradoxical finding.
Nonetheless, it is evident that omega-3 is good for brain health. It may at least delay Alzheimer’s onset or slow down its progress. Furthermore, omega-3mega-3 fatty acids are more effective when their regular intake is started much earlier than the diagnosis, as reversing the established disease is highly unlikely.
Although it is too early to make any firm recommendations based on these findings, the study cannot be regarded as conclusive due to the small sample size. Nevertheless, it can form the basis of further studies. There is a need for identifying the role of high omega-3 intake in preventing Alzheimer’s in more extensive clinical trials or population-based studies.
1. Dyall SC. Long-chain omega-3 fatty acids and the brain: a review of the independent and shared effects of EPA, DPA and DHA. Frontiers in Aging Neuroscience. 2015;7. doi:10.3389/fnagi.2015.00052
2. Tofiq A, Zetterberg H, Blennow K, et al. Effects of Peroral Omega-3 Fatty Acid Supplementation on Cerebrospinal Fluid Biomarkers in Patients with Alzheimer’s Disease: A Randomized Controlled Trial—The OmegAD Study. Journal of Alzheimer’s Disease. 2021;83(3):1291-1301. doi:10.3233/JAD-210007