Longevity & Aging · Supplements
olive oil decreases all-cause mortality
In plain terms: Does olive oil help you live longer?
Strong support Longevity & Aging 🔬 Includes disconfirming
Part of: • Olive oil
RefutedContestedStrong support
consensus score 1.00
Higher olive oil intake is consistently linked to lower risk of dying over time - roughly 10-17% lower - and swapping butter or margarine for olive oil looks beneficial. It's mostly observational, and the one randomized trial showed a clear heart-death benefit but didn't quite reach significance for overall mortality. Encouraging and low-risk.
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
7 support 0 contradict 1 tested null 0 mixed · 8 sources, 7 independent groups · 4 superseded — pooled inside a review, counted once
What the evidence shows
Higher olive oil intake is consistently associated with living longer: several dose-response meta-analyses put all-cause mortality roughly 10–17% lower at higher intakes (about 8% lower per 10 g/day), backed by large cohorts (the Nurses'/Health Professionals studies, EPIC-Spain, Moli-sani) that also show benefit from swapping butter or margarine for olive oil.
The evidence (13)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Ke Y et al. 2024 · Food Funct | meta-analysis | supports | high | Dose-response meta 30 studies (2.7M): all-cause mortality RR 0.85; 8% lower per 10 g/d. |
| Del Saz-Lara A et al. 2024 · Food Funct | meta-analysis | supports | moderate | Systematic review + DerSimonian-Laird random-effects meta-analysis of prospective cohorts, searched to October 2024: 'Fourteen studies were included in the systematic review and seven in the meta-analysis.' Pooled all-cause mortality: 'an association between OO consumption and reduction in all-cause mortality (HR: 0.85; 95% CI: 0.80-0.91)', summarised as a 15% reduction. Right claim, right direction, but only seven cohorts pooled (fewer than xia-2022's 13, already moderate here) and the paywalled abstract reports no heterogeneity, risk-of-bias, GRADE or publication-bias figures, and no PROSPERO registration - quality moderate rather than high. Its seven cohorts are nested inside the far larger oo-ke-2024 and oo-martinez-2022 pools. |
| Zhang Y, Chadaideh KS, Li Y, Li Y, Gu X, Liu Y, Guasch-Ferre M, Rimm EB, Hu FB, Willett WC, Stampfer MJ, Wang DD 2025 · JAMA Intern Med 2025;185(5):549-560 | observational | supports | high | NHS + NHSII + HPFS, 221,054 US adults, up to 33 y, 50,932 deaths: olive oil per 5 g/d HR 0.92 (95% CI 0.91-0.94) for total mortality, P for trend < .001. (The 17% mortality reduction for swapping 10 g/d butter is for TOTAL plant-based oils - safflower, soybean, corn, canola, olive - not olive oil alone.) |
| Tessier AJ et al. 2024 · JAMA Netw Open | observational | supports | moderate | OFF-SCOPE for all-cause mortality: NHS + HPFS, 92,383 US adults free of CVD/cancer at 1990 baseline, 28 y, 2,183,095 person-years - but the only modelled outcome is cause-specific. 'Main Outcome and Measure Dementia death was ascertained from death records' and 'Participants were censored at death from causes other than dementia'; the 37,649 total deaths appear once as context ('this study documented a total of 4751 dementia deaths (3473 in NHS and 1278 in HPFS; 37 649 total deaths)') and are never modelled. Direction on the endpoint it did measure is uniformly inverse, not mixed: 'Consuming at least 7 g/d of olive oil was associated with a 28% lower risk of dementia-related death (adjusted pooled HR, 0.72 [95% CI, 0.64-0.81]) compared with never or rarely consuming olive oil', holding after APOE e4 adjustment (HR 0.66) - though it is carried by women (HR 0.67 [0.59-0.77]) and null in men (HR 0.87 [0.69-1.09]). The all-cause estimate for this exact sample belongs to the group sibling Guasch-Ferre 2022, which the authors cite as their own prior work: 'Recently, we showed that olive oil consumption was associated with a lower risk of total and cause-specific mortality in large US prospective cohort studies'. Read from PMC full text 2026-08-19. |
| Buckland G et al. 2012 · Am J Clin Nutr | observational | supports | high | EPIC-Spain cohort (40,622 adults from 5 Spanish regions, 13.4 y, 1915 deaths), olive oil measured directly: 'In comparison with nonconsumers, the highest quartile of olive oil consumption was associated with a 26% (95% CI: 13%, 36%) reduction in risk of overall mortality'. Continuous, energy-adjusted estimate (which avoids the atypical nonconsumer reference group): 'For each increase in olive oil of 10 g · 2000 kcal⁻¹ · d⁻¹, there was a 7% (95% CI: 3%, 10%) decreased risk of overall mortality'. Same cohort as oo-buckland-2011 (shared group_id epic-spain-buckland); this is the informative member of that pair. ↩ SUPERSEDED — pooled in the review above, counted once |
| Ruggiero E et al. 2024 · Eur J Clin Nutr | observational | supports | high | Moli-sani (22k): >3 tbsp/d olive oil HR 0.80 all-cause mortality, independent of diet quality. |
| Guasch-Ferre M et al. 2022 · J Am Coll Cardiol | observational | supports | high | NHS+HPFS, 92,383 US adults, 28 y, 36,856 deaths: highest olive-oil intake (>7 g/d) vs never/rarely, pooled HR 0.81 (95% CI 0.78-0.84) for all-cause mortality; substituting 10 g/d of margarine, butter, mayonnaise or dairy fat with olive oil was associated with 8%-34% lower mortality. But: 'No significant associations were observed when olive oil was compared with other vegetable oils combined.' ↩ SUPERSEDED — pooled in the review above, counted once |
| Martinez-Gonzalez MA et al. 2022 · Clin Nutr | meta-analysis | supports | moderate | Outcome-wide systematic review + random-effects meta-analysis of prospective cohorts (searched through January 2022): 36 studies in the SR, 27 pooled — 'twenty-seven studies (24 prospective cohorts and 3 different reports from one RCT) were assessed in 4 quantitative random-effects meta-analyses.' All-cause-mortality pool: 733,420 participants with 174,081 deaths; 'inversely associated with all-cause mortality (RR: 0.89; 95% CI: 0.85 to 0.93, per 25 g/d).' Direction supports the claim on a tight CI, but two things temper it to moderate rather than high: the paper's own heterogeneity admission — 'Only the results for T2D were homogeneous. Specific sources of heterogeneity for the other 3 outcomes were not always apparent' — and the pool counting a single RCT as three separate reports. Abstract-grade only (Elsevier paywall, not in PMC), so no forest plots, risk-of-bias or publication-bias figures are visible, and no PROSPERO registration is stated. Its cohorts are nested inside the larger, later oo-ke-2024 pool (30 cohort articles / 2,710,351 participants, searched to March 2024). ↩ SUPERSEDED — pooled in the review above, counted once |
| Guasch-Ferre M et al. 2014 · BMC Med | observational | tested-null | moderate | OBSERVATIONAL cohort analysis inside PREDIMED (n=7,216, 323 all-cause deaths, median 4.8 y; exposure = baseline FFQ olive-oil tertiles measured before randomization, NOT a randomized comparison). All-cause mortality was pre-specified and came back null: 'No statistically significant associations were found for cancer mortality and all-cause mortality.' Table 2 model 3, top vs bottom tertile of total olive oil, HR 0.78 (0.58 to 1.05), P for trend 0.18; per 10 g/d 0.94 (0.87 to 1.00). EVOO alone (Table 3 model 3) 0.82 (0.61 to 1.09), P for trend 0.25. The authors' own reading: 'Our findings suggest a non-significant possible inverse relation between each 10 g/d (one tablespoon of oil) increase in total olive oil and EVOO consumption and all-cause mortality.' The one estimate that reaches significance is a SECONDARY repeated-measures GEE analysis on post-randomization intake — 'a relative risk reduction of 25% (HR: 0.75; 95% CI: 0.56 to 1.00' — with the upper bound exactly on the null, so it does not carry a supports vote. Cardiovascular mortality DID reach significance (HR 0.52; 0.29 to 0.93, 81 deaths) but that is a different outcome and belongs to the CVD claim, not this one. Quality moderate: prospective, adjudication committee 'blinded to treatment allocation and to the dietary habits of participants', extensively adjusted; against self-reported FFQ exposure (validity r=0.60), conceded residual confounding, and trial oil donated by the Fundación Patrimonio Comunal Olivarero and Hojiblanca SA. [Full PMC XML incl. Tables 1-4 read 2026-08-19.] |
| Zhang Y et al. 2021 · BMC Med | observational | supports | high | NIH-AARP Diet and Health Study, 521,120 US adults aged 50-71, '129,328 deaths were documented during a median follow-up of 16 years.' On the claim's own outcome (all-cause mortality), Model 3 vs non-consumers: T1 0.96 (0.94-0.99), T2 0.97 (0.95-0.98), T3 '0.96 (95% CI, 0.95–0.98) for olive oil', P-trend < 0.001, and continuously 'each 1-tablespoon/day increment of canola oil or olive oil consumption was associated with 2% and 3% of reductions in all-cause mortality, respectively'. Swapping fats helps more than adding oil: 'Substituting 1 tablespoon/day (8 g/day) corn oil, canola oil, or olive oil for equivalent amounts of butter was associated with 5%, 6%, and 7% lower all-cause mortality, respectively.' Stance (supports), grade (observational) and quality (high) all stand — n, >99% follow-up, adjustment for HEI-2015/energy/all other oils, and robustness to a 4-year lag, exclusion of prevalent disease and a propensity score. The PREVIOUS EXTRACT DID NOT: it quoted 'HR 0.96/tbsp cardiometabolic mortality', which is the wrong outcome for this claim (the cardiometabolic figure is 0.96 per tablespoon, the all-cause figure is 0.97 per tablespoon / 0.96 by tertile) — right by coincidence, not by citation. Three caveats belong on this vote. (1) Dose: top-tertile olive-oil intake was a median 3.8 g/day (IQR 2.6-6.2) against a modelled 1-tablespoon = 8 g/day increment, and the authors concede 'the overall intake level of individual vegetable oils was low in this population with a relatively narrow intake range' — the tertile HR is the estimate observed data supports, the per-tablespoon HR extrapolates ~2x past it. (2) Exposure was captured once at baseline (1995-96) and 'Portion sizes for individual oils/fats were estimated based on the 1994–1996 USDA Continuing Survey of Food Intakes by Individuals (CSFII)', so between-person contrast is frequency-driven with an imputed portion. (3) 'the inverse association of olive oil consumption with all-cause mortality was restricted to alcohol drinkers' (P-interaction = 0.003), an explicit residual-confounding signal; 'Finally, a causal relationship may not be established due to the observational nature.' POOL NOTE: this is not a null and should not be described as one — 0.96 (0.95-0.98) is significant with very tight CIs; it anchors the LOW-EFFECT end of the I2 = 93% mortality pool against NHS/HPFS at 0.79-0.81, and the low-intake range above is the likeliest reason. DOUBLE-COUNT: oo-xia-2022 this note and pools this exact 0.96 (0.95-0.98) estimate as ~73% of its participants. |
| Xia M, Zhong Y, Peng Y, Qian C 2022 · Front Nutr | meta-analysis | supports | moderate | Random-effects meta-analysis of prospective cohorts (PubMed + Scopus to 31 Jul 2022): 'the highest intake of olive oil was related to an obvious decrease in the risk of all-cause mortality (RR: 0.83, 95% CI: 0.77-0.90, p < 0.001), with substantial between-study heterogeneity (I2 = 93%, p < 0.001)'; 5 g/day increment RR 0.96, and 'For all-cause death, there seemed no preventive effects when increasing the intake level beyond 20 g/days.' Stance and quality (moderate) both stand; the count in the previous extract does not — the mortality pool is not 13 cohorts: 'A total of 11 independent cohorts from 10 publications have reported the risk of all-cause mortality, comprising 713,000 subjects and 173,817 deaths.' The I2 of 93% is structural, not noise: Figure 2 shows the Guasch-Ferre NHS/HPFS cohorts at RR 0.79-0.81 against the single largest cohort, Zhang 2021 NIH-AARP (n = 521,120, 73% of the pooled participants), at RR 0.96 (0.95-0.98), with Trichopoulou 2003 null (0.96, 0.83-1.11) — so the headline 17% reduction describes none of the large contributing cohorts well. Publication bias negative (AS-Thompson p = 0.175), all included studies NOS >= 7, leave-one-out stable, clean non-industry funding. Pool is nested inside oo-ke-2024 and overlaps oo-martinez-2022 almost completely (733,420 participants / 174,081 deaths there vs 713,000 / 173,817 here). ↩ SUPERSEDED — pooled in the review above, counted once |
| Zou X, Liu H 2025 · Food Sci Nutr | meta-analysis | supports | moderate | Umbrella review (PROSPERO CRD420251146945) of 19 systematic reviews/meta-analyses, searched only to 22 Nov 2023; it POOLS NOTHING OF ITS OWN — 'The estimated summary effect with 95% CI and dose–response was extracted from every eligible article.' On all-cause mortality it re-states two already-published estimates: 'OO showed a protective effect on all‐cause mortality (SHR = 0.94, 95% CI: 0.92, 0.97), and every 25 g/day OO intake was associated with an 11% lower relative risk of all‐cause mortality with potential heterogeneity (RR = 0.89, 95% CI: 0.85, 0.93)' — which is verbatim the Martinez-Gonzalez 2022 pool the vault already holds as oo-martinez-2022 (RR 0.89, 0.85-0.93 per 25 g/d, 733,420 participants / 174,081 deaths) — plus an all-MUFA-combined figure the umbrella itself grades very low: 'The risk of all‐cause mortality was significantly reduced when correlated with MUFA from multiple sources (RR = 0.89, 95% CI: 0.83, 0.96)'. Direction is protective and the umbrella's own GRADE for it is moderate, but this is a restatement, not new data: its Table 6 mortality row carries I2 = 65.20 and an Egger p of 0.00, and the authors warn '75% of the studies did not report publication bias, causing a significant lack of transparency and potentially inflating effects in the original meta‐analyses.' Counting it in the primary layer would double-count oo-martinez-2022, so role = review (precedent u). |
| Buckland G et al. 2011 · Br J Nutr | observational | supports | low | EPIC-Spain cohort (40 622 adults, 13.4 y, 1855 deaths). The measured exposure is a composite 18-unit rMED score over nine components, not olive oil: 'A high compared with a low rMED score was associated with a significant reduction in mortality from all causes (hazard ratio (HR) 0·79; 95 % CI 0·69, 0·91)'. Olive oil enters only as an attribution - 'A high olive oil intake and moderate alcohol consumption contributed most to this association' - with no standalone olive-oil hazard ratio reported. Right direction, weak claim-specific weight; the direct olive-oil analysis of this same cohort is oo-buckland-2012. |
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