26 Scientific Studies on Avocado

Avocados

Native to South America and the Caribbean, the avocado tree produces a fruit that is actually a large egg-shaped berry with a sizable seed at its center. Its use among pre-Incan and other ancient Mesoamerican cultures has been dated to about ten thousand years ago by archaeologists. The Aztecs considered avocado to be a fertility booster.

Though dozens of avocado cultivars are harvested, the Hass cultivar accounts for three-fourths of all avocados consumed. Mexico remains by far the biggest producer. Avocados contain much more potassium than bananas, are high in monounsaturated fats and B vitamins, and have a high fiber content. They have proven health benefits in many areas, particularly in lowering levels of harmful LDL and triglycerides and raising levels of beneficial HDL.

Anti-Inflammatory

AV119, a Natural Sugar from Avocado gratissims, Modulates the LPS-Induced Proinflammatory Response in Human Keratinocytes. Donnarumma G, Paoletti I, Buommino E, Et al. Inflammation. 2010 Oct 9 (Epub ahead of print). Key Finding: “Our data show that AV119, a patented blend of avocado sugars, is able to modulate significantly the proinflammatory response in human keratinocytes, blocking the NF-kB activation in human keratinocytes.”

Atherosclerosis

Hypoglycemia and hypocholesterolemic potential of Persea Americana leaf extracts. Brai BI, Odetola AA, Agomo PU. J Med Food. 2007 Jun;10(2):356-60. Key Finding: “These results suggest that aqueous and methanolic leaf extracts of P. Americana (avocado) lower plasma glucose and influence lipid metabolism in hypercholesterolemic rats with consequent lowering of T-CHOL and LDL-CHOL, and a restoration of HDL-CHOL levels. This could represent a protective mechanism against the development of atherosclerosis.”

Cancer (oral; prostate)

Selective induction of apoptosis of human oral cancer cell lines by avocado extracts via a ROS-mediated mechanism. Ding H, Han C, Guo D, Chin YW, Ding Y, Kinghorn AD, D’Ambrosio SM. Nutr Cancer. 2009;61(3):348-56. Key Finding: “Avocados have a high content of phytochemicals with potential chemo preventive activity. Previously we reported that phytochemicals extracted from avocado meat selectively induced apoptosis in cancer but not normal, human oral epithelial cell lines. In the present study, we observed that treatment of human oral cancer cell lines containing high levels of reactive oxygen (ROS) with D003 increased ROS levels twofold to threefold and induced apoptosis. These data suggest that perturbing the ROS levels in human oral cancer cell lines may be a key factor in selective apoptosis and molecular targeting for chemoprevention by photochemical.”

Chemoproventive characteristics of avocado fruit. Ding H, Chin YW, Kinghorn AD, D’Ambrosio SM. Semin Cancer Biol. 2007 Oct;17(5):386-94. Key Finding: “Our recent studies indicate that phytochemicals extracted with chloroform from avocado fruits target multiple signaling pathways and increase intracellular reactive oxygen leading to apoptosis. This review summarizes the reported phytochemicals in avocado fruit and discusses their molecular mechanisms and targets. These studies suggest that individual and combinations of phytochemicals from the avocado fruit may offer an advantageous dietary strategy in cancer prevention.”

Inhibition of prostate cancer cell growth by an avocado extract: role of lipid-soluble bioactive substances. Lu QY, Arteaga JR, Zhang Q, Huerta S, Go VL, Heber D. J Nutr Biochem. 2005 Jan;16(1):23-30. Key Finding: “Avocado contains numerous bioactive carotenoids. Because the avocado also contains a significant amount of monounsaturated fat, these bioactive carotenoids are likely to be absorbed into the bloodstream, where in combination with other diet-derived phytochemicals they may contribute to the significant cancer risk reduction associated with a diet of fruits and vegetables.”

An avocado constituent, persenone A, suppresses expression of inducible forms of nitric oxide synthase and cyclooxygenase in macrophages, and hydrogen peroxide generation in mouse skin. Kim OK, Murakami A, Takahashi D, Nakamura Y, Torikai K, Kim HW, Ohigashi H. Biosci Biotechnol Biochem. 2000 Nov;64(11):2504-7. Key Finding: “This study suggests that persenone A, an avocado constituent, is a possible agent to prevent inflammation-associated diseases including cancer.”

Cholesterol (and Hypercholesterolemia)

High-density lipoproteins (HDL) size and composition are modified in the rat by a diet supplemented with “Hass” avocado (Persea Americana Miller). Perez-Mendez O, Garcia Hernandez L. Arch Cardiol Mex. (Spanish). 2007 Jan-Mar;77(1):17-24. Key Finding: “The inclusion of avocado in the diet decreased plasma triglycerides increased HDL-cholesterol plasma levels and modified HDL structure. The latter effect may enhance the antiatherogenic properties of HDL.”

Effects of a vegetarian diet vs. a vegetarian diet enriched with avocado in hypercholesterolemic patients. Carrznza-Madrigal J, Herrera-Abarca JE, Alvizouri-Munoz M, Alvarado-Jimenez MR, Chavez-Carbajal F. Arch Med Res. 1997 Winter;28(4):537-41. Key Finding: “All three diets reduced HDL levels. To obtain beneficial effects on lipid profile with avocado, lower amounts of carbohydrates and polyunsaturated fatty acids are probably needed.”

Monounsaturated fatty acid (avocado) rich diet for mild hypercholesterolemia. Lopez LR, Frati Munari AC, Hernandez Dominguez BC, Cervantes MS, Hernandez Luna MH, Juarez C, Moran LS. Arch Med Res. 1996 Winter;27(4):519-23. Key Finding: “High lipid, high MFA-avocado enriched diet can improve lipid profile in healthy and especially in mild hypercholesterolemic patients, even if hypertriglyceridemia (combined hyperlipidemia) is present.”

Effects of avocado on the level of blood lipids in patients with phenotype II and IV dyslipidemias. Carranza J, Alvizouri M, Alvarado MR, Chavez F, Gomez M, Herrera JE. Arch Inst Cardio Mex. (Spanish). 1995 Jul-Aug;65(4):342-8. Key Finding: “Avocado is an excellent source of monounsaturated fatty acids in diets designed to treat hypercholesterolemia with some advantages over low-fat diets with a greater amount of carbohydrates.”

Carotenoid absorption from salad and salsa by humans is enhanced by the addition of avocado or avocado oil. Unlu NZ, Bohn T, Clinton SK, Schwartz SJ. J Nutr. 2005 Mar;135(3):431-6. Key Finding: “Adding avocado fruit can significantly enhance carotenoid absorption from salad and salsa, which is attributed primarily to the lipids present in avocado.”

Hypertension

Cardiovascular effects of Persea Americana Mill (Lauraceae) (avocado) aqueous leaf extract in experimental animals. Ojewole JA, Kamadyaapa DR, Gondwe MM, Moodley K, Musabayane CT. Cardiovasc J Afr. 2007 Mar-Apr;18(2):69-76. Key Finding: “The findings of this study tend to suggest that P. Americana leaf could be used as a natural supplementary remedy in essential hypertension and certain cases of cardiac dysfunctions.”

Effect of an avocado oil-rich diet over an angiotensin II-induced blood pressure response. Salazar MJ, El Hafidi M, Pastelin G, Ramirez-Ortega MC, Sanchez-Mendoza MA. J Ethnopharmacol. 2005 Apr 26;98(3):335-8. Key Finding: “Avocado oil-rich diet modifies the fatty acid content in cardiac and renal membranes in a tissue-specific manner. Diet content can be a key factor in vascular responses.”

Osteoarthritis

A potential role for avocado and soybean based nutritional supplements in the management of osteoarthritis: a review. Dinubile NA. Phys Sportsmed. 2010 Jun;38(2):71-81. Key Finding: “Basic scientific research studies and a systematic review and meta-analysis of the available high-quality randomized clinical trials indicate that 300 mg of avocado and soybean unsaponifiables per day (with or without glucosamine and chondroitin sulfate) appears to be beneficial for patients with hip or knee osteoarthritis.”

Symptomatic efficacy of avocado-soybean unsaponifiables (ASU) in osteoarthritis (OA) patients: a meta-analysis of randomized controlled trials. Christensen R, Bartels EM, Astrup A, Bliddal H. Osteoarthritis Cartilage. 2008 Apr;16(4):399-408. Key Finding: “Based on the available evidence, patients may be recommended to give avocado/soybean unsaponifiables a chance for e.g., 3 months. Meta-analysis data support better chances of success in patients with knee OA than in those with hip OA.”

Avocado/soybean unsaponifiables in the treatment of knee and hip osteoarthritis. Angermann P. Ugeskr Laeger (Danish). 2005 Aug 15;167(33):3023-5. Key Finding: “These studies indicate that ASU has an effect on the symptoms of knee and hip osteoarthritis but not on the structural changes caused by osteoarthritis.”

Avocado-soybean unsaponifiables (ASU) for osteoarthritis—a systematic review. Ernst E. Clin Rheumatol. 2003 Oct;22(4-5):285-8. Key Finding: “The majority of rigorous trial data available to date suggest that avocado/soybean unsaponifiables is effective for the symptomatic treatment of osteoarthritis.”

Structural effect of avocado/soybean unsaponifiables on joint space loss in osteoarthritis of the hip. Lequesne M, Maheu E, Cadet C, Dreiser RL. Arthritis Rheum. 2002 Feb;47(1):50-8. Key Finding: “Avocado/soybean unsaponifiables significantly reduced the progression of joint space loss as compared with placebo in the subgroup of patients with advanced joint space narrowing.”

Symptoms modifying effect of avocado/soybean unsaponifiables (ASU) in knee osteoarthritis. A double-blind, prospective, placebo-controlled study. Appelboom T, Schuermans J, Verbruggen G, Henrotin Y, Reginster JY. Scand J Rheumatol. 2001;30(4):242-7. Key Finding: “The efficacy of ASU at a dosage of 300mg/day and 600mg/day was consistently superior to that of placebo at all endpoints, with no differences observed between the two doses.”

Modification of articular cartilage and subchondral bone pathology in an ovine meniscetomy model of osteoarthritis by avocado and soya unsaponifiables (ASU). Cake MA, Read RA, Guillou B, Ghosh P. Osteoarthritis Cartilage. 2000 Nov;8(6):404-11. Key Finding: “These findings support other studies which have proposed that avocado and soya unsaponifiables may exhibit disease-modifying anti-osteoarthritis activity.”

The possible ‘chondroprotective’ effect of the unsaponifiable constituents of avocado and soya in vivo. Khayyal MT, el-Ghazaly MA. Drugs Exp Clin Res. 1998;24(1):41-50. Key Finding: “An experimental in vivo model for studying cartilage destruction has been used to study the possible chondroprotective effect of the unsaponifiable constituents of avocado, soya and their combination. The unsaponifiables of both avocado and soya significantly reduced the degenerative changes induced by the granuloma tissue on the implanted cartilage in control animals. The effect was even more marked when animals were treated with the combination of the two unsaponifiables at a 1:2 ratio.”

Efficacy and safety of avocado/soybean unsaponifiables in the treatment of symptomatic osteoarthritis of the knee and hip. A prospective, multicenter, three-month, randomized, double-blind, placebo-controlled trial. Blotman F, Maheu E, Wulwik A, Caspard H, Lopez A. Rev Rhum Engl Ed. 1997 Dec;64(12):825-34. Key Finding: “One of the objectives of symptomatic slow-acting drugs for osteoarthritis is to reduce the need for drugs with a less favorable safety profile, mainly analgesics and non-steroidal anti-inflammatory drugs. Avocado/soybean unsaponifiables reduced the need for these drugs in patients with primary femorotibial or hip osteoarthritis. The functional index showed a significantly greater improvement in the active (avocado/soybean) group.”

Psoriasis

Vitamin B(12) cream containing avocado oil in the therapy of plaque psoriasis. Stucker M, Memmel U, Hoffmann M, Hartung J, Altmeyer P. Dermatology. 2001;203(2):141-7. Key Finding: “The results of this clinical trial provide evidence that the recently developed vitamin B (12) cream containing avocado oil has considerable potential as a well-tolerated, long-term topical therapy of psoriasis.”

The effect of various avocado oils on skin collagen metabolism. Werman MJ, Mokady S, Nimni ME, Neeman I. Connect Tissue Res. 1991;26(1-2):1-10. Key Finding: “The effects of various avocado oils on collagen metabolism in skin were studied in growing rats. Rats fed the unrefined avocado oil extracted with hexane from the intact fruit, its unsaponifiables or the avocado seed oil, showed significant increases in soluble collagen content in skin.”

Schleroderma

Natural remedies for schleroderma. Gaby AR. Altern Med Rev. 2006 Sep;11(3):188-95. Key Finding: Avocado/soybean extract is a promising natural treatment for scleroderma, an autoimmune disease of the connective tissue characterized by fibrosis and thickening of various tissues.

Wounds

Wound healing activity of Persea Americana (avocado) fruit: a preclinical study on rats. Nayak BS, Raju SS, Chalapathia Rao AV. J Wound Care. 2008 Mar;17(3):123-6. Key Finding: “Avocado oil is rich in nutrient waxes, proteins and minerals, as well as vitamins A, D and E. It is an excellent source of enrichment for dry, damaged or chapped skin. This study aimed to evaluate the wound-healing activity of fruit extract of Persea Americana in rats. Rate of wound contraction, epithelialization time, together with the hydroxyproline content and histological observations, supports the use of Persea Americana in the management of wound healing.”