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Omega-3 fatty acids and dementia
Cole GM, Ma QL, Frautschy SA.. Prostaglandins, leukotrienes, and essential fatty acids, 2009-06-12
Topic: Amyloid, tau and blood-test diagnosis
More than a dozen epidemiological studies have reported that reduced levels or intake of omega-3 fatty acids or fish consumption is associated with increased risk for age-related cognitive decline or dementia such as Alzheimer's disease (AD). Increased dietary consumption or blood levels of docosahexaenoic acid (DHA) appear protective for AD and other dementia in multiple epidemiological studies; however, three studies suggest that the ApoE4 genotype limits protection. DHA is broadly neuroprotective via multiple mechanisms that include neuroprotective DHA metabolites, reduced arachidonic acid metabolites, and increased trophic factors or downstream trophic signal transduction. DHA is also protective against several risk factors for dementia including head trauma, diabetes, and cardiovascular disease. DHA is specifically protective against AD via additional mechanisms: It limits the production and accumulation of the amyloid beta peptide toxin that is widely believed to drive the disease; and it also suppresses several signal transduction pathways induced by Abeta, including two major kinases that phosphorylate the microtubule-associated protein tau and promote neurofibrillary tangle pathology. Based on the epidemiological and basic research data, expert panels have recommended the need for clinical trials with omega-3 fatty acids, notably DHA, for the prevention or treatment of age-related cognitive decline--with a focus on the most prevalent cause, AD. Clinical trials are underway to prevent and treat AD. Results to-date suggest that DHA may be more effective if it is begun early or used in conjunction with antioxidants.
Key findings
- More than a dozen epidemiological studies have reported that reduced levels or intake of omega-3 fatty acids or fish consumption is associated with increased risk for age-related cognitive decline or dementia such as Alzheimer's disease (AD).
- Increased dietary consumption or blood levels of docosahexaenoic acid (DHA) appear protective for AD and other dementia in multiple epidemiological studies; however, three studies suggest that the ApoE4 genotype limits protection.
- Results to-date suggest that DHA may be more effective if it is begun early or used in conjunction with antioxidants.
Why it matters
This review reports that higher intake or blood levels of DHA appeared protective for Alzheimer's disease in several observational studies, but three studies suggested the ApoE4 genotype limits that protection. It calls for clinical trials and does not show that omega-3 fatty acids prevent or treat dementia.
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Study details
- Evidence strengthLow
How this study scored 45/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Prostaglandins, leukotrienes, and essential fatty acids) |
| Journal's citation record | 1 / 4 | Prostaglandins Leukotrienes and Essential Fatty Acids: journal h-index 138 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2009 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 268 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 14.1 citations a year over 19 year(s) since 2009 |
| Impact for its field and year | 4 / 6 | Cited 18.3× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 3 other studies in this library |
| Still being cited | 3 / 4 | Cited 51 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Sally Ann Frautschy: h-index 64 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of California, Los Angeles: institution h-index 1,923 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 19523795) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 45 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1016/j.plefa.2009.05.015
- PubMed: 19523795
- Original source →
- Free full text: PubMed Central →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Cole, G. M., Ma, Q. L., & Frautschy, S. A. (2009). Omega-3 fatty acids and dementia. Prostaglandins, leukotrienes, and essential fatty acids. https://doi.org/10.1016/j.plefa.2009.05.015
Vancouver
Cole GM, Ma QL, Frautschy SA. Omega-3 fatty acids and dementia. Prostaglandins, leukotrienes, and essential fatty acids. 2009. doi:10.1016/j.plefa.2009.05.015. PMID: 19523795.
BibTeX
@article{cole2009-19523795,
author = {Cole, G. M. and Ma, Q. L. and Frautschy, S. A.},
title = {{Omega-3 fatty acids and dementia}},
journal = {Prostaglandins, leukotrienes, and essential fatty acids},
year = {2009},
doi = {10.1016/j.plefa.2009.05.015},
pmid = {19523795},
url = {https://doi.org/10.1016/j.plefa.2009.05.015}
}
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