Plant Comparison
Shiitake (mushroom) vs Olive
A side-by-side comparison of two medicinal plants — every documented constituent, action, use, safety note and cited source, assembled automatically from the Omnia Sana database.
At a glance
Shiitake (mushroom) and Olive: they share 7 indicated uses (blood sugar / diabetes support, cancer (anticancer research), cardiovascular / heart health, …); 5 pharmacological actions in common.
Evidence face-off — shared uses
| Condition | Shiitake (mushroom) | Olive | Verdict |
|---|---|---|---|
| Blood sugar / diabetes support | 5/10 | 6/10 | Comparable evidence |
| Cancer (anticancer research) | 2/10 | 2/10 | Comparable evidence |
| Cardiovascular / heart health | 5/10 | 5/10 | Comparable evidence |
| Cold & flu | 5/10 | 5/10 | Comparable evidence |
| Infection (general) | 5/10 | 5/10 | Comparable evidence |
| Metabolic support | 5/10 | 5/10 | Comparable evidence |
| Wounds | 5/10 | 5/10 | Comparable evidence |
Evidence scores (1–10) are computed from the tier of each cited source. “Comparable” means the two scores are within one point. Follow a score to its detailed sources.
Key Constituents
The principal immunomodulatory polysaccharide, used clinically in Japan as an injectable cancer-adjuvant therapy.
A unique amino-acid-derived compound studied for cholesterol-lowering activity.
The principal bioactive phenolics of the leaf, responsible for most of its antioxidant, anti-inflammatory and antihypertensive activity.
Antioxidant flavonoids of the leaf.
Pentacyclic triterpenes of the leaf cuticle and fruit skin, studied for anti-inflammatory and metabolic effects.
The dominant fatty acid of the fruit oil, a key component of the Mediterranean-diet lipid profile.
Pharmacological Actions
Traditional & Indicated Uses
inferred from antidiabetic action
inferred from anticancer action
inferred from antimicrobial action
inferred from antidiabetic action
inferred from anti-inflammatory action
inferred from antidiabetic action
inferred from anticancer action
inferred from antimicrobial action
inferred from anti-inflammatory action
inferred from antidiabetic action
inferred from anti-inflammatory action
Safety, Cautions & Contraindications
Generally very safe as a food. Raw or undercooked shiitake can cause a rare skin rash (shiitake dermatitis / flagellate dermatitis) in sensitive individuals — fully cooking eliminates this risk. May have mild anticoagulant effects. Rarely causes digestive upset. Well tolerated in normal culinary quantities.
Duke (2002) rates shiitake as +++ and notes immunostimulant, hypocholesterolemic, antibacterial, and anti-HIV activities at the experimental level (score 1). The key active compound is lentinan, a beta-1,3-glucan polysaccharide, which is used as an injectable anticancer drug in Japan. Duke notes clinical applications of shiitake preparations for immune support, cancer adjuvant therapy, and cholesterol management. Dose: 1–3 (606 mg) capsules up to three times daily for standardized preparations. Shiitake dermatitis (flagellate erythema) is a rare but recognized adverse effect from eating raw or undercooked shiitake — cooking prevents this (Duke, 2002).
Olive leaf extract may lower blood pressure; use caution if already on antihypertensive medication. May have mild hypoglycaemic effects. Olive oil is safe for dietary use. Rare olive pollen allergy. Well tolerated in normal culinary and supplement doses.
Duke (2002) includes olive leaf as ++ and notes hypotensive, hypoglycemic, ACE inhibitor-like, and antioxidant activities at the experimental level (score 1). Olive leaf extract (containing oleuropein) has demonstrated blood pressure-lowering and antiarrhythmic effects consistent with clinical support (PHR). Duke notes that traditional Mediterranean use for both the leaf and fruit is food-grade and safe. Olive leaf preparations are used as mild antihypertensives in European phytotherapy. No significant adverse effects are reported at standard herbal doses (Duke, 2002).
External Ids
Botanical Description
Wood-decay fungus (not a true plant) with a classic cap-and-stem mushroom form. The cap is broad, brown to dark brown, often with pale scale-like markings, with a fringed or curled margin when young; the underside bears numerous cream-coloured gills radiating from a central or slightly off-centre fibrous stem.
Evergreen tree (Oleaceae), typically 3-15 m tall, often gnarled and long-lived, with some specimens surviving for centuries. Leaves are narrow, leathery, lance-shaped, dark green above and silvery-grey beneath. Small, fragrant, creamy-white four-lobed flowers are borne in axillary clusters, followed by a fleshy drupe (the olive) that ripens from green to purple-black.[1]
Habitat
Grows naturally as a wood-decay fungus on fallen broadleaf trees (notably shii, oak and chestnut) in East Asian forests; almost all commercial shiitake today is cultivated on hardwood logs or sawdust blocks.
Native to the Mediterranean basin, the Near East and parts of Africa, and cultivated for millennia across Mediterranean-type climates worldwide (warm, dry summers and mild winters); tolerates poor, rocky, calcareous soils and drought.[1]
Harvesting
Fruiting bodies are hand-picked once the cap has opened but before the margin fully flattens, then used fresh or dried; mycelium-based extracts are cultivated separately in liquid or grain culture.
Leaves can be harvested year-round from pruned or fallen branches, generally at their highest oleuropein content in late autumn and winter; fruit is hand- or machine-harvested from early autumn (green olives) through winter (fully ripe black olives), depending on the intended product.[10]
Traditional Uses
Shiitake has a very long East Asian culinary and medicinal tradition, used in Chinese and Japanese medicine as a tonic for vitality and longevity and to support healthy qi and blood; its polysaccharide lentinan, isolated from the fruiting body, has been used clinically in Japan as an adjunct immunotherapy, directly building on this traditional immune-tonic reputation.[11]
Olive leaf and fruit have a long Mediterranean tradition as a tonic, antipyretic and mild antihypertensive remedy, and olive oil is the foundation fat of the traditional Mediterranean diet, long associated with cardiovascular health. Modern research on oleuropein and other leaf polyphenols supports antioxidant, anti-inflammatory, antimicrobial, blood-pressure-lowering and insulin-sensitising effects consistent with these traditional and dietary uses.[1, 4, 7]
Preparations
References
Lookalikes Review
Dosage
Not documented
A meta-analysis of trials for blood pressure used around 500 mg/day of standardised olive leaf extract. Educational reference only, not a prescription; culinary olive oil and leaf tea are considered food-safe at normal dietary amounts.
Drug Class Interactions
Not documented
Pairings
Not documented
Olive leaf and black seed (Nigella sativa) can each mildly lower blood pressure, so taking them together — especially alongside blood-pressure medicines — may add up and lower blood pressure more than expected. Monitor your blood pressure.[11, 18]
References & Sources
- Jafari, M., Boskabady, M.H., Rezaee, S.A., Rezaeian, S. and others (2023) 'Lentinan and beta-glucan extract from shiitake mushroom, Lentinula edodes, alleviate acute LPS-induced hematological changes in mice', Iranian Journal of Basic Medical Sciences, 26(7), pp. 836-842. doi:10.22038/IJBMS.2023.67669.14820 Preclinical
https://doi.org/10.22038/IJBMS.2023.67669.14820 - Ahn, H., Jeon, E., Kim, J.C., Kang, S.G. and others (2017) 'Lentinan from shiitake selectively attenuates AIM2 and non-canonical inflammasome activation while inducing pro-inflammatory cytokine production', Scientific Reports, 7(1), pp. 1314. doi:10.1038/s41598-017-01462-4 Preclinical
https://doi.org/10.1038/s41598-017-01462-4 - Okamoto, T., Kodoi, R., Nonaka, Y., Fukuda, I. and others (2004) 'Lentinan from shiitake mushroom (Lentinus edodes) suppresses expression of cytochrome P450 1A subfamily in the mouse liver', BioFactors, 21(1-4), pp. 407-409. doi:10.1002/biof.552210180 Preclinical
https://doi.org/10.1002/biof.552210180 - Ng, M.L. and Yap, A.T (2002) 'Inhibition of human colon carcinoma development by lentinan from shiitake mushrooms (Lentinus edodes)', Journal of Alternative and Complementary Medicine, 8(5), pp. 581-589. doi:10.1089/107555302320825093 Preclinical
https://doi.org/10.1089/107555302320825093 - Bisen, P.S., Baghel, R.K., Sanodiya, B.S., Thakur, G.S. and Prasad, G.B.K.S (2010) 'Lentinus edodes: a macrofungus with pharmacological activities', Current Medicinal Chemistry, 17(22), pp. 2419-2430. doi:10.2174/092986710791698495 Meta-analysis / review
https://doi.org/10.2174/092986710791698495 - Stephany, M.P., Chung, S., Handler, M.Z., Handler, N.S. and others (2016) 'Shiitake Mushroom Dermatitis: A Review', American Journal of Clinical Dermatology, 17(5), pp. 485-489. doi:10.1007/s40257-016-0212-6 Meta-analysis / review
https://doi.org/10.1007/s40257-016-0212-6 - Nguyen, A.H., Gonzaga, M.I., Lim, V.M., Adler, M.J. and others (2017) 'Clinical features of shiitake dermatitis: a systematic review', International Journal of Dermatology, 56(6), pp. 610-616. doi:10.1111/ijd.13433 Meta-analysis / review
https://doi.org/10.1111/ijd.13433 - Djordjevic, B., Skugor, S., Jorgensen, S.M., Overland, M. and others (2009) 'Modulation of splenic immune responses to bacterial lipopolysaccharide in rainbow trout (Oncorhynchus mykiss) fed lentinan, a beta-glucan from mushroom Lentinula edodes', Fish & Shellfish Immunology, 26(2), pp. 201-209. doi:10.1016/j.fsi.2008.10.012 Preclinical
https://doi.org/10.1016/j.fsi.2008.10.012 - Kaleta, B., Gorski, A., Zagozdzon, R., Cieslak, M. and others (2019) 'Selenium-containing polysaccharides from Lentinula edodes-Biological activity', Carbohydrate Polymers, 223, pp. 115078. doi:10.1016/j.carbpol.2019.115078 Preclinical
https://doi.org/10.1016/j.carbpol.2019.115078 - Money, N.P (2016) 'Are mushrooms medicinal?', Fungal Biology, 120(4), pp. 449-453. doi:10.1016/j.funbio.2016.01.006 Meta-analysis / review
https://doi.org/10.1016/j.funbio.2016.01.006 - Vethanayagam, R.R. et al (1996) 'Lentinan — a novel immunomodulator', 54(2), pp. 25--30. Traditional / reference
https://scholar.google.com/scholar?q=Lentinan%20%E2%80%94%20a%20novel%20immunomodulator - Wasser, S.P (2011) 'Current findings, future trends, and unsolved problems in studies of medicinal mushrooms', 89(5), pp. 1323--1332. doi:10.1007/s00253-010-3067-4 Randomized trial
https://doi.org/10.1007/s00253-010-3067-4 - Yokota, M (1989) 'Observatory trial of anti-obesity activity of Eritadenine', pp. 1--4. Traditional / reference
https://scholar.google.com/scholar?q=Observatory%20trial%20of%20anti-obesity%20activity%20of%20Eritadenine - Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition
- Omar, S.H., Kerr, P.G., Scott, C.J., Hamlin, A.S. and others (2017) 'Olive (Olea europaea L.) Biophenols: A Nutriceutical against Oxidative Stress in SH-SY5Y Cells', Molecules, 22(11), pp. 1858. doi:10.3390/molecules22111858 Preclinical
https://doi.org/10.3390/molecules22111858 - Ruzzolini, J., Peppicelli, S., Andreucci, E., Bianchini, F. and others (2018) 'Oleuropein, the Main Polyphenol of Olea europaea Leaf Extract, Has an Anti-Cancer Effect on Human BRAF Melanoma Cells and Potentiates the Cytotoxicity of Current Chemotherapies', Nutrients, 10(12), pp. 1950. doi:10.3390/nu10121950 Preclinical
https://doi.org/10.3390/nu10121950 - Al-Rimawi, F., Sbeih, M., Amayreh, M., Rahhal, B. and others (2024) 'Evaluation of the antibacterial and antifungal properties of oleuropein, Olea europaea leaf extract, and Thymus vulgaris oil', BMC Complementary Medicine and Therapies, 24(1), pp. 297. doi:10.1186/s12906-024-04596-x Preclinical
https://doi.org/10.1186/s12906-024-04596-x - Qabaha, K., Al-Rimawi, F., Qasem, A. and Naser, S.A (2018) 'Oleuropein Is Responsible for the Major Anti-Inflammatory Effects of Olive Leaf Extract', Journal of Medicinal Food, 21(3), pp. 302-305. doi:10.1089/jmf.2017.0070 Preclinical
https://doi.org/10.1089/jmf.2017.0070 - Pang, K.L., Lumintang, J.N. and Chin, K.Y (2021) 'Thyroid-Modulating Activities of Olive and Its Polyphenols: A Systematic Review', Nutrients, 13(2), pp. 529. doi:10.3390/nu13020529 Meta-analysis / review
https://doi.org/10.3390/nu13020529 - Kheirandish, F., Mosaffa, N., Tarahi, M.J. and Fallahi, S (2018) 'Olive (Olea europaea) leaf extract alters the cytokine profile of Leishmania major-infected macrophages: New insight into the underlying mechanism', Parasite Immunology, 40(4), pp. e12520. doi:10.1111/pim.12520 Preclinical
https://doi.org/10.1111/pim.12520 - de Bock, M., Derraik, J.G., Brennan, C.M., Biggs, J.B. and others (2013) 'Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial', PLoS One, 8(3), pp. e57622. doi:10.1371/journal.pone.0057622 Randomized trial
https://doi.org/10.1371/journal.pone.0057622 - Pasban-Aliabadi, H., Esmaeili-Mahani, S., Sheibani, V., Abbasnejad, M. and others (2013) 'Inhibition of 6-hydroxydopamine-induced PC12 cell apoptosis by olive (Olea europaea L.) leaf extract is performed by its main component oleuropein', Rejuvenation Research, 16(2), pp. 134-142. doi:10.1089/rej.2012.1384 Preclinical
https://doi.org/10.1089/rej.2012.1384 - Imperatrice, M., Lasfar, A., van Kalkeren, C.A.J. and Troost, F (2024) 'Olive Leaf Extract Supplementation Improves Postmenopausal Symptoms: A Randomized, Double-Blind, Placebo-Controlled Parallel Study on Postmenopausal Women', Nutrients, 16(22), pp. 3879. doi:10.3390/nu16223879 Randomized trial
https://doi.org/10.3390/nu16223879 - de Bock, M., Thorstensen, E.B., Derraik, J.G., Henderson, H.V. and others (2013) 'Human absorption and metabolism of oleuropein and hydroxytyrosol ingested as olive (Olea europaea L.) leaf extract', Molecular Nutrition & Food Research, 57(11), pp. 2079-2085. doi:10.1002/mnfr.201200795 Preclinical
https://doi.org/10.1002/mnfr.201200795 - Ismail, M.A., Norhayati, M.N. and Mohamad, N (2021) 'Olive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysis', PeerJ, 9, pp. e11173. doi:10.7717/peerj.11173 Meta-analysis / review
https://doi.org/10.7717/peerj.11173 - Boskov Hansen, H.C. et al (2012) 'Oleocanthal, a phenolic derived from virgin olive oil: a review of the beneficial effects on inflammatory disease', 13(9), pp. 11628--11670. doi:10.3390/ijms150712323 Traditional / reference
https://doi.org/10.3390/ijms150712323 - Wainstein, J. et al (2012) 'Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats', 15(7), pp. 605--610. doi:10.1089/jmf.2011.0243 Randomized trial
https://doi.org/10.1089/jmf.2011.0243 - Waterman, E. and Lockwood, B (2007) 'Active components and clinical applications of olive oil', 12(4), pp. 331--342. Preclinical
https://scholar.google.com/scholar?q=Active%20components%20and%20clinical%20applications%20of%20olive%20oil - Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition - de Bock, M., Derraik, J.G.B., Brennan, C.M., Biggs, J.B., Morgan, P.E., Hodgkinson, S.C., Hofman, P.L. and Cutfield, W.S (2013) 'Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial', PLoS One, 8(3), pp. e57622. doi:10.1371/journal.pone.0057622 Randomized trial
https://doi.org/10.1371/journal.pone.0057622 - Willcox, M.L., Elugbaju, C., Al-Anbaki, M., Lown, M. and Graz, B (2021) 'Effectiveness of Medicinal Plants for Glycaemic Control in Type 2 Diabetes: An Overview of Meta-Analyses of Clinical Trials', Frontiers in Pharmacology, 12, pp. 777561. doi:10.3389/fphar.2021.777561 Meta-analysis / review
https://doi.org/10.3389/fphar.2021.777561 - Sahebkar, A., Soranna, D., Liu, X., Thomopoulos, C., Simental-Mendia, L.E., Derosa, G., Maffioli, P. and Parati, G (2016) 'A systematic review and meta-analysis of randomized controlled trials investigating the effects of supplementation with Nigella sativa (black seed) on blood pressure', Journal of Hypertension, 34(11), pp. 2127-2135. doi:10.1097/HJH.0000000000001049 Meta-analysis / review
https://doi.org/10.1097/HJH.0000000000001049
Generated automatically from the Omnia Sana plant database and its cited sources. For educational purposes only — not medical advice. Always consult a qualified practitioner before using medicinal plants.