Can Extra Virgin Olive Oil Raise Testosterone? What a Clinical Trial on 60 Men Found
Most people know olive oil is good for the heart. Far fewer know that a peer-reviewed clinical study found switching from butter to extra virgin olive oil raised testosterone levels by 17.4% and luteinizing hormone by 42.6% in just three weeks — both statistically highly significant. Here is the full breakdown of the science, the mechanisms, and what it means for men's hormonal health.
The Question Nobody Is Asking About Testosterone
Men's testosterone levels have been falling at roughly 1% per year for the past four decades. By some estimates, a 40-year-old man today has testosterone levels 25–30% lower than a 40-year-old man in 1980. The usual culprits cited are endocrine disruptors, sedentary lifestyles, obesity, and chronic stress — but dietary fat quality rarely makes the headlines.
Yet a 2013 peer-reviewed clinical trial published in Natural Product Communications found that simply replacing dietary fat — swapping butter for extra virgin olive oil — raised testosterone by 17.4% and more than doubled the increase in luteinizing hormone (LH), rising by 42.6%, in just three weeks. These were healthy young men, not hypogonadal patients on supplementation protocols.
This paper has been largely underappreciated in mainstream health media. A 2025 systematic review in the Journal of Advanced Research has now synthesized the mechanistic underpinning of exactly how EVOO achieves this, pointing to at least four distinct biological pathways. Here is the full clinical and mechanistic story.
Advertisement
Study Overview
Citation
Derouiche A, Jafri A, Driouch I, El Khasmi M, Adlouni A, Benajiba N, Bamou Y, Saile R, Benouhoud M. Natural Product Communications. 2013 Jan;8(1):51–3.
PMID
23472458
Study Design
Randomized controlled nutritional intervention
Population
60 healthy adult Moroccan men, ages 23–40
Intervention
2-week butter stabilization → randomized to virgin argan oil or EVOO for 3 weeks
Outcomes Measured
Serum testosterone (T), luteinizing hormone (LH), dehydroepiandrosterone sulfate (DHEAS), body weight, BMI, blood pressure, energy intake
Institution
Université Hassan II Mohammedia Casablanca, Laboratory of Research on Lipoproteins and Atherosclerosis (URAC 34)
Statistical Test
Mann-Whitney (between groups); Wilcoxon signed-rank (within group pre/post)
The design is straightforward but elegant. To isolate the effect of dietary fat type on androgen production, researchers first standardized all participants on a butter-based diet for two weeks — establishing a reliable hormonal baseline. Then they randomly allocated the men into two groups: one consuming virgin argan oil (VAO) as their primary dietary fat, the other consuming extra virgin olive oil (EVO), for three weeks.
Both groups maintained their habitual diets otherwise; only the fat source changed. Blood was drawn at the end of the stabilization period and again at the end of the 3-week intervention. The study controlled for energy intake (no significant change) and anthropometric parameters (no significant changes in weight or BMI), making dietary fat quality the only meaningful variable.
Key Findings: The Numbers
+17.4%
Testosterone (EVOO group)
p < 0.0001
+42.6%
LH (EVOO group)
p < 0.0001
N.S.
DHEAS / BMI / BP
No significant change
The primary headline: 3 weeks of replacing butter with EVOO produced a 17.4% increase in serum testosterone (p < 0.0001 by Wilcoxon test). For context, this is a meaningful clinical change. Testosterone-replacement therapy trials often use 10–20% improvements as benchmarks for therapeutic efficacy. Achieving this through diet alone, in healthy men without deficiency, is notable.
Even more striking was the luteinizing hormone (LH) response. LH is the pituitary signal that instructs the testes (specifically Leydig cells) to synthesize testosterone. The EVOO group showed a 42.6% increase in LH (p < 0.0001). This is important because it tells us the effect is not merely peripheral — it is happening at the hypothalamic-pituitary-gonadal (HPG) axis level. The brain is sensing a change in the nutritional environment and signaling for more testosterone production.
DHEAS (dehydroepiandrosterone sulfate) — an adrenal androgen and indirect precursor to testosterone — did not change significantly. This suggests the primary action is gonadal (testicular) rather than adrenal, pointing to a specific mechanism in Leydig cell steroidogenesis rather than a general adrenal stimulation.
Crucially, body weight, BMI, blood pressure, and daily energy intake showed no significant variation in either group. This rules out confounding by caloric changes or weight loss, which are known testosterone modulators. The dietary fat swap alone drove the hormonal shift.
⚖️ EVOO vs. Argan Oil Comparison
For completeness: the virgin argan oil group raised testosterone by 19.9% (slightly higher than EVOO) but showed only 18.5% LH increase — less than half the pituitary response of EVOO. This divergence suggests different dominant mechanisms between the two oils. Argan oil (rich in linoleic acid, an omega-6 PUFA) may act more peripherally on steroidogenesis, while EVOO's high monounsaturated fat and polyphenol content appears to more powerfully activate the HPG axis at the central level.
The Biological Mechanisms: How Does EVOO Raise Testosterone?
The Derouiche study established that EVOO raises testosterone. A 2025 systematic review by Liu et al. in the Journal of Advanced Research (PMID 41274640) synthesized the clinical literature on dietary patterns and androgens, identifying four distinct mechanisms through which olive oil specifically supports testosterone synthesis. These operate at different levels of the endocrine cascade.
1. The MUFA Advantage: Substrate Quality for Leydig Cells
Testosterone is a steroid hormone — it is synthesized from cholesterol. But not all dietary fats support steroidogenesis equally. Leydig cells in the testes are surrounded by membranes whose fluidity and receptor function depend heavily on fatty acid composition. Monounsaturated fatty acids (MUFA), particularly oleic acid (C18:1) which constitutes 55–83% of EVOO, appear to optimize the membrane environment for testosterone biosynthetic enzymes including CYP11A1 (cholesterol side-chain cleavage enzyme) and 3β-HSD (3-beta-hydroxysteroid dehydrogenase). Studies show that diets high in MUFA are associated with significantly higher testosterone levels compared to diets high in saturated fat (butter) or very low-fat diets.
2. SREBP2 Pathway Restoration: Unlocking the Cholesterol Supply Chain
The rate-limiting step in testosterone synthesis is cholesterol delivery into the mitochondria of Leydig cells via the steroidogenic acute regulatory protein (StAR). The upstream regulator of intracellular cholesterol synthesis and import is the transcription factor SREBP2 (sterol regulatory element-binding protein 2). Liu et al. (2025) identified that olive oil consumption specifically enhances testicular SREBP2 activity, restoring optimal cholesterol flux into steroidogenic pathways. This is particularly relevant when dietary fat quality has been poor, as with saturated fat (butter) diets — exactly the comparison condition in the Derouiche trial.
3. COX Inhibition: Oleocanthal as a Testicular Anti-Inflammatory
Oleocanthal, the signature bitter phenolic in fresh EVOO, has been repeatedly demonstrated to inhibit both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) — the same enzymes targeted by ibuprofen. This anti-inflammatory activity matters enormously in the testes. Chronic low-grade testicular inflammation suppresses Leydig cell testosterone output via prostaglandin E2 and pro-inflammatory cytokines (IL-1β, TNF-α). By reducing this inflammatory tone, oleocanthal removes a brake on testosterone production. Liu et al. explicitly name this mechanism as a distinguishing feature of the Mediterranean diet's androgen-supporting effects. Crucially, the effect is dose-dependent — higher-polyphenol EVOO (greater than 500 mg/kg of oleocanthal) would be expected to produce stronger anti-inflammatory and testosterone-supporting effects than low-phenolic refined olive oil.
4. Hydroxytyrosol as a Testicular Antioxidant Shield
Leydig cells are paradoxically vulnerable to oxidative stress despite their central role in steroidogenesis. Testosterone synthesis involves mitochondrial electron transport processes that generate reactive oxygen species (ROS) as byproducts. Excessive ROS damages StAR protein function and suppresses steroidogenic gene expression. Hydroxytyrosol — the most potent antioxidant in EVOO, with an ORAC value approximately 10× that of green tea catechins — crosses the blood-testis barrier and scavenges these ROS directly within testicular tissue. Animal studies (Xiong et al., 2022, Food & Function, PMID 35904366) demonstrated that hydroxytyrosol supplementation at 25 mg/kg improved cardiac mitochondrial function during strenuous exercise via precisely this mechanism. In the testes, the same mitochondrial protection logic applies. This explains why switching from butter (no antioxidants) to EVOO (rich in hydroxytyrosol) would produce measurable hormonal change within weeks.
Context: How Does This Compare to Previous Research?
The Derouiche study does not stand alone. It fits into a coherent body of evidence linking dietary fat quality to androgen levels.
Several large epidemiological studies have shown that men following Mediterranean dietary patterns — high in EVOO, vegetables, fish, and legumes, low in processed foods and saturated fat — have significantly higher testosterone levels than men following Western dietary patterns. A 2020 meta-analysis in Nutrients found Mediterranean diet adherence was inversely associated with hypogonadism risk (OR 0.52, 95% CI 0.38–0.71), meaning Mediterranean diet followers had roughly half the odds of low testosterone.
At the dietary fat level, the evidence is fairly consistent: very low-fat diets suppress testosterone (likely by restricting cholesterol and steroid hormone precursors), while high-saturated-fat diets from processed sources correlate with lower testosterone through obesity-mediated aromatase upregulation. Monounsaturated fat from olive oil sits in a "sweet spot" — providing adequate fatty acid substrate without the obesogenic or inflammatory drawbacks of saturated fats from processed food sources.
The 2025 Liu et al. review adds specificity: of the four major dietary patterns analyzed (ketogenic, vegetarian, Mediterranean, Western), the Mediterranean diet's testosterone effects were unique in being "synergistic" — driven by multiple bioactive compounds (oleocanthal, hydroxytyrosol, oleuropein, oleic acid, resveratrol from wine, omega-3s from fish) acting on multiple pathways simultaneously, rather than any single mechanism.
Advertisement
Practical Takeaway: What Should You Actually Do?
Evidence-Based Action Plan
Replace saturated fats from processed sources with EVOO
The Derouiche trial's effect came from a butter → EVOO swap. This is realistic and practical. Butter as a cooking fat can be largely replaced with high-quality EVOO without caloric inflation if portions are similar.
Prioritize high-polyphenol EVOO (250+ mg/kg)
The testosterone mechanisms depend substantially on polyphenol content — oleocanthal for COX inhibition, hydroxytyrosol for testicular antioxidant protection. Refined olive oil contains almost no polyphenols and likely provides only the MUFA substrate benefit. You need high-phenolic EVOO for the full hormonal package. Early-harvest, fresh-pressed oils from high-phenol cultivars (Koroneiki, Picual, Coratina, Moraiolo) are the best choices.
Consume 2–4 tablespoons daily (25–50 mL)
The trial used EVOO as the primary dietary fat — not a supplement dose. Spreading 2–4 tablespoons across meals (on salads, vegetables, used in cooking at moderate temperatures below 180°C) is the practical approach. Avoid high-heat frying which degrades polyphenols.
Pair with a broader Mediterranean dietary pattern
EVOO's testosterone effects appear synergistic within a Mediterranean diet context. Zinc-rich foods (seafood, legumes), omega-3s (fatty fish), and moderate overall fat intake amplify the hormonal benefits. Alcohol and ultra-processed foods work against them.
Allow at least 3 weeks of consistent use
The Derouiche trial showed significant hormonal change in just 3 weeks. This is consistent with the expected timeframe for dietary fat changes to alter cell membrane composition and steroidogenic enzyme activity. Results won't appear in 3 days.
Note: None of this constitutes medical advice. Men with diagnosed hypogonadism should work with a physician. Dietary changes should complement, not replace, medical evaluation of androgen disorders.
Limitations: What Are the Caveats?
Small Sample Size (n = 60)
Sixty participants — 30 per arm — is adequate for detecting large effect sizes but underpowered for more nuanced analyses (e.g., subgroup effects by age, baseline testosterone, or dietary pattern). Replication in larger cohorts is needed to confirm these findings across diverse populations.
Short Duration (3 Weeks)
Three weeks is enough time to see a hormonal response but insufficient to assess long-term sustainability, dose-response curves, or whether the testosterone increase is maintained over months. It is possible that testosterone levels plateau or that the body adapts through feedback mechanisms over time. No follow-up data exist.
Specific Study Population
Participants were healthy young Moroccan men (ages 23–40) — a population that was presumably not eating large amounts of olive oil at baseline (the stabilization diet was butter-based). The effect may be less pronounced in populations already consuming high-EVOO Mediterranean diets, or in older men with age-related declines in Leydig cell function. Generalizability to Western populations or to men with medical conditions is unconfirmed.
Lack of Polyphenol Quantification
The study does not specify the polyphenol content of the EVOO used. As noted, polyphenol concentration varies enormously between EVOO products (from <50 mg/kg in some commercial oils to >1,000 mg/kg in high-phenolic early-harvest varieties). Without this specification, it is impossible to determine whether the hormonal effect is primarily driven by MUFA, by polyphenols, or by both, and what threshold polyphenol content is required.
Published in 2013 — Awaiting Replication
Remarkably, in the 13 years since publication, this finding has not been directly replicated in a larger, double-blind, placebo-controlled trial with polyphenol-quantified EVOO. The 2025 Liu et al. review synthesizes mechanistic support for the finding but does not add new human clinical data. This is a gap in the literature that warrants attention.
Our Take: Is This Study Strong? Weak? Game-Changing?
The honest verdict: this is a compelling study that deserves far more attention than it has received — but it is not the last word.
The strengths are real. It is a randomized, controlled dietary intervention with a sensible baseline period, appropriate statistical tests (non-parametric, given likely non-normal distribution of hormone levels), and clean results: highly significant p-values on the primary outcomes with no confounding by energy intake or body composition changes. The mechanistic explanations are plausible and increasingly well-supported by molecular biology.
The weakness is that it is a single relatively small study from 2013 that has never been directly replicated at scale. Science requires replication. A 17.4% testosterone increase sounds dramatic, but without a multi-site, larger-sample, double-blind trial with carefully characterized EVOO, it cannot be elevated to "established fact."
That said, the directional finding — that MUFA and polyphenols from EVOO support testosterone production through multiple plausible mechanisms — fits coherently into what we know about steroidogenesis, Leydig cell biology, and the broader epidemiology of Mediterranean diet and male reproductive health. You don't change your fat sources exclusively to raise testosterone, but if you are eating EVOO daily for cardiovascular, anti-inflammatory, and cognitive benefits, the hormonal upside is a legitimate co-benefit worth understanding.
The specific insight that LH increased by 42.6% — far more than argan oil — implies central HPG axis stimulation and is arguably the most interesting finding in the paper. It suggests EVOO's unique polyphenol profile (not just MUFA) communicates something to the hypothalamic-pituitary system. Exactly what that signal is remains an open question. The LH mechanism deserves dedicated investigation.
References
1. Derouiche A, Jafri A, Driouch I, et al. “Effect of argan and olive oil consumption on the hormonal profile of androgens among healthy adult Moroccan men.” Nat Prod Commun. 2013 Jan;8(1):51–3. PMID: 23472458
2. Liu X, Li X, Cai D, Sun J, Bai W. “Dietary patterns and testosterone balance: a review of clinical data and perspectives.” J Adv Res. 2025 Nov 20 (ahead of print). doi: 10.1016/j.jare.2025.11.016. PMID: 41274640
3. Xiong Y, Xu J, Cao W, et al. “Hydroxytyrosol improves strenuous exercise-associated cardiac pathological changes via modulation of mitochondrial homeostasis.” Food Funct. 2022 Aug 15;13(16):8676–8684. PMID: 35904366
4. Visioli F, et al. “Hydroxytyrosol excretion differs between rats and humans and depends on the vehicle of administration.” J Nutr. 2003 Aug;133(8):2612–5. (Antioxidant properties of EVOO polyphenols)
5. Beauchamp GK et al. “Phytochemistry: ibuprofen-like activity in extra-virgin olive oil.” Nature. 2005 Sep 1;437(7055):45–6. (Oleocanthal COX inhibition) PMID: 16136122