Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (698 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
The glyceryl esters of a fatty acid, or of a mixture of fatty acids. They are generally odorless, colorless, and tasteless if pure, but they may be flavored according to origin. Fats are insoluble in water, soluble in most organic solvents. They occur in animal and vegetable tissue and are generally obtained by boiling or by extraction under pressure. They are important in the diet (dietary fats) as a source of energy. (Grant and Hackh's Chemical Dictionary, 5th ed)
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Where it fits in the MeSH classification
- Broader topics
- Lipids
- Narrower topics
- Dietary Fats; Fats, Unsaturated
Related concepts
- Dietary Fats
Research landscape
PubMed indexes 121,273 records tagged with the MeSH heading “Fats” (counts retrieved 2026-10-31). 16,474 of them (13.6%) were published from 2020 onward, and the busiest period so far is through 1999 with 45,081 records.
Reviews account for 13,406 records (11.1%) and meta-analyses for 1,128. Randomized controlled trials number 8,606 (7.1%) as a share of all records on the topic.
Show the data
| Period | Records |
|---|---|
| through 1999 | 45,081 |
| 2000-2009 | 25,511 |
| 2010-2019 | 34,207 |
| 2020 onward | 16,474 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 13,406 | 11.1% |
| Meta-analyses | 1,128 | 0.9% |
| Randomized controlled trials | 8,606 | 7.1% |
Method: PubMed query "Fats"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in drugs and chemicals
Studies of a chemical or drug can answer very different questions: what it is and how it behaves in cells and animals, how the body handles it, and whether it changes outcomes in people. Laboratory and animal findings often do not carry over to patients, and observational studies of exposures are confounded by who uses a substance and why. Nothing on this page is a recommendation to use, avoid, start or stop any substance or medicine; talk to a qualified clinician or pharmacist about your own situation. Check the dose, the species, the comparison group and whether a patient-relevant outcome was measured.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
N-3 Fatty Acids (EPA and DHA) and Cardiovascular Health - Updated Review of Mechanisms and Clinical Outcomes [1]
Abstract reading summary — source excerpts
- Opening excerpt
- Purpose of reviewWe synthesize the latest evidence (published 2020 to 2025) on the role of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in cardiovascular health, emphasizing biological mechanisms and key findings from observational studies and clinical trials related to cardiovascular disease (CVD) risk and outcomes.
- Closing excerpt
- Moderate intake appears safe and protective, while high dose EPA may offer added benefits in high-risk individuals but also might increase AF risk.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (164 words)
Purpose of reviewWe synthesize the latest evidence (published 2020 to 2025) on the role of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in cardiovascular health, emphasizing biological mechanisms and key findings from observational studies and clinical trials related to cardiovascular disease (CVD) risk and outcomes.Recent findingsEPA and DHA modulate lipid metabolism, inflammation, platelet and endothelial function, the gut-heart axis, ion channels and autonomic function via vagal tone, supporting cardiovascular health. While individual RCTs have produced variable results, updated cohort data and recent meta-analyses consistently link higher intake or circulating levels of EPA and DHA to reduced risk of cardiovascular events. However, evidence from RCTs indicates that high-dose supplementation may be associated with an increase in atrial fibrillation (AF) risk. Evidence supports a role for EPA and DHA in CVD prevention and treatment, with effects influenced by dose, formulation, and individual variability. Moderate intake appears safe and protective, while high dose EPA may offer added benefits in high-risk individuals but also might increase AF risk.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41247613 · DOI · PMC12628397
Omega-3 Source Matters: Comparative Lipid Signatures and Quantitative Distribution of EPA/DHA Across Marine Resources [2]
Abstract reading summary — source excerpts
- Opening excerpt
- Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential omega-3 polyunsaturated fatty acids (n-3 PUFAs) with well-established health benefits.
- Closing excerpt
- Beyond total n-3 content in relation to recommended daily intake values, the lipid-class distribution and nutritional indices should be considered decisive metrics for evaluating the health relevance of n-3 resources in the human diet.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (193 words)
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential omega-3 polyunsaturated fatty acids (n-3 PUFAs) with well-established health benefits. They occur primarily in marine resources, while their quantitative distribution within the glycerolipidome is rarely analyzed. Therefore, we investigated major commercial sources, including 12 microalgal species, the protist Schizochytrium sp., four fish species, and nine commercial n-3 supplements (fish, krill and Schizochytrium-derived "algal" oils) by high-performance thin-layer chromatography-gas chromatography-mass spectrometry (HPTLC-GC-MS). The class-resolved mapping of EPA and DHA revealed signature lipid profiles across all sources. In microalgae, 60-80% of EPA was localized in glycolipids, whereas in Schizochytrium and fish, >90% of DHA occurred in triacylglycerols. Krill oils exhibited phospholipid-rich profiles with ~70% of phosphatidylcholine-bound DHA. Nutritional indices also highlighted major differences: fish and fish oils showed favorable PUFA-to-saturated FA ratios (>0.45) and hypocholesterolemic-to-hypercholesterolemic ratios (>1), while Schizochytrium-based "algal" oils even surpassed these values. The microalgae Nannochloropsis granulata contained the highest EPA content in biomass form, combined with favorable nutritional indices. Beyond total n-3 content in relation to recommended daily intake values, the lipid-class distribution and nutritional indices should be considered decisive metrics for evaluating the health relevance of n-3 resources in the human diet.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41590701 · DOI · PMC12843360
Moderate increase in dietary fat induces alterations of microbiota and metabolome along the digestive tract prior to systemic metabolic changes: insights from a pig model [3]
Abstract reading summary — source excerpts
- Opening excerpt
- The small intestine is a key site for nutrient sensing and host-microbiota interactions, yet how it functionally adapts to dietary changes remains poorly understood.
- Closing excerpt
- This study also underscores the importance of considering both region- and sex-specific responses in diet-microbiota-metabolome research.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (195 words)
The small intestine is a key site for nutrient sensing and host-microbiota interactions, yet how it functionally adapts to dietary changes remains poorly understood. Using a translational porcine model, we investigated the impact of moderate dietary fat increase on the gut microbiota and metabolome across five locations in the digestive tract. Pigs were fed either a low-fat (3%) or a medium-fat (12%) diet for 12 weeks without developing obesity. Multiomics profiling revealed significant dietary effects on bile and duodenojejunal metabolomic profiles, particularly lipid and stachydrine, with notable sex-specific responses. These metabolite shifts were accompanied by segment- and sex-specific changes in microbial communities, including the depletion of metabolically beneficial taxa (e.g., Limosilactobacillus reuteri and Lactobacillus johnsonii) and the enrichment of bacteria linked to metabolic dysfunction (e.g., Streptococcus alactolyticus). In the small intestine lumen, multiple bacterial-metabolite associations correlated with host metabolic markers, suggesting early diet-induced alterations with potential relevance for metabolic disease onset. Our findings position the small intestine as a critical site for early diet-induced microbial and metabolic remodeling, potentially influencing metabolic disease risk and shaping the downstream intestinal environment. This study also underscores the importance of considering both region- and sex-specific responses in diet-microbiota-metabolome research.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41327907 · DOI · PMC12674348
The association between omega-3 supplementation and cognitive decline in older adults [4]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundWhile omega-3 fatty acid supplementation is widely used for cognitive protection, its efficacy remains controversial, and its impact on core Alzheimer's disease (AD) pathologies in humans is not well-established.
- Closing excerpt
- These findings challenge the prevailing view of omega-3 as uniformly beneficial and highlight the need for a cautious reassessment of its widespread use for cognitive protection.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (146 words)
BackgroundWhile omega-3 fatty acid supplementation is widely used for cognitive protection, its efficacy remains controversial, and its impact on core Alzheimer's disease (AD) pathologies in humans is not well-established.MethodsThis longitudinal study utilized data from the Alzheimer's Disease Neuroimaging Initiative (ADNI). We employed linear mixed-effects models to assess the association between omega-3 supplementation and longitudinal cognitive decline, and mediation analyses to examine whether this relationship was mediated by core AD pathologies (Aβ-PET, tau-PET, T1-MRI, FDG-PET).ResultsOmega-3 supplementation was associated with significantly accelerated cognitive decline, as evidenced by a faster decrease in MMSE scores (β = -0.266, p ConclusionsOmega-3 supplementation may be associated with accelerated cognitive decline in older adults, potentially through adverse effects on cerebral synaptic function rather than classical AD proteinopathies. These findings challenge the prevailing view of omega-3 as uniformly beneficial and highlight the need for a cautious reassessment of its widespread use for cognitive protection.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 42000571 · DOI · PMC13099475
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Efficacy of omega-3 PUFAs in depression: A meta-analysis [5]
- Research article Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality [6]
- Research article Omega-3 fatty acid addition during pregnancy [7]
- Research article Marine Omega-3 Supplementation and Cardiovascular Disease: An Updated Meta-Analysis of 13 Randomized Controlled Trials Involving 127 477 Participants [8]
- Research article Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease [9]
- Research article Dietary Cholesterol and Cardiovascular Risk: A Science Advisory From the American Heart Association [10]
References
- Djuricic I, Calder PC. N-3 Fatty Acids (EPA and DHA) and Cardiovascular Health - Updated Review of Mechanisms and Clinical Outcomes. . 2025. PMID 41247613 · DOI · PMC12628397
- Makay K, Griehl C, Schilling S, Grewe C. Omega-3 Source Matters: Comparative Lipid Signatures and Quantitative Distribution of EPA/DHA Across Marine Resources. . 2025. PMID 41590701 · DOI · PMC12843360
- Ranson A, Vazquez Gomez M, Alili R, Durrafourd J, Vitalis O, Taillandier P, et al.. Moderate increase in dietary fat induces alterations of microbiota and metabolome along the digestive tract prior to systemic metabolic changes: insights from a pig model. . 2025. PMID 41327907 · DOI · PMC12674348
- Liao ZB, Hu ZC, Zeng GH, Chen J, Li XP, Liu YH, et al.. The association between omega-3 supplementation and cognitive decline in older adults. . 2026. PMID 42000571 · DOI · PMC13099475
- Liao Y, Xie B, Zhang H, He Q, Guo L, Subramanieapillai M, et al.. Efficacy of omega-3 PUFAs in depression: A meta-analysis. Transl Psychiatry. 2019. PMID 31383846 · DOI · PMC6683166
- Marklund M, Wu JHY, Imamura F, Del Gobbo LC, Fretts A, de Goede J, et al.. Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality. Circulation. 2019. PMID 30971107 · DOI · PMC6582360
- Middleton P, Gomersall JC, Gould JF, Shepherd E, Olsen SF, Makrides M. Omega-3 fatty acid addition during pregnancy. Cochrane Database Syst Rev. 2018. PMID 30480773 · DOI · PMC6516961
- Hu Y, Hu FB, Manson JE. Marine Omega-3 Supplementation and Cardiovascular Disease: An Updated Meta-Analysis of 13 Randomized Controlled Trials Involving 127 477 Participants. J Am Heart Assoc. 2019. PMID 31567003 · DOI · PMC6806028
- Abdelhamid AS, Brown TJ, Brainard JS, Biswas P, Thorpe GC, Moore HJ, et al.. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2020. PMID 32114706 · DOI · PMC7049091
- Carson JAS, Lichtenstein AH, Anderson CAM, Appel LJ, Kris-Etherton PM, Meyer KA, et al.. Dietary Cholesterol and Cardiovascular Risk: A Science Advisory From the American Heart Association. Circulation. 2020. PMID 31838890 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.