Aloe vera has been used by many cultures since ancient times. Early records of use appear in the 16th century BC Eber Papyrus. It was a component of the cosmetic beautifying regimes of Egyptian queens Nefertii and Cleopatra. It has been used in ancient wars for treatment of wounds. It held folkloric status as a herbal cure-all until the mid-1930s, when it found application in the treatment of chronic and severe radiation dermatitis. Today it is a component of countless beauty, health, and skin care products.
Sabila is an herb plant growing 30 to 40 centimeters high. Leaves arising
from the ground are smooth, thick, fleshy, mucilaginous, succulent, 20 to 50 centimeters long, 5 to 8 centimeters wide, light green with white blotches, narrow-lanceolate,
tapering, spiny-toothed margins. Flowering stalk is erect, usually twice the height
of the plant. Flowers are 2 to 3 centimeters long, yellow, with segments that about equals the oblong tube.
- Cultivated for ornamental and medicinal purposes.
- Introduced; a native of Africa.
- Occurs in subtemperate and tropical regions.
- Commonly raised in clay pots or perforated containers.
in the yard; ordinary garden soil with compost is best.
its growth as lower leaves are cut, perpetuating availability
of the material.
• Aromatic, astringent, aperient,
purgative, emmenagogue, emollient, cholagogue, laxative, stomachic,
• Considered antitoxic, anticancer, antimutagenic.
- Contains more than 75 active constituents: vitamins, enzymes, minerals, sugars, lignin, saponins, salicylic acids and amino acids.
Aloin; barbaloin, 25%; isobarbaloin resin, 12.5%; (sicaloin;
emodin; cinnamic acid; b-arabinose; oxidase); cinnamic acid;
resin up to 20% (aloesin, aloesone, aloeresin A and C); coumarins,
traces of volatile oil.
- Freeze-dried leaves of Aloe vera yielded aloe-emodin, feralolide, a mixture of aloins A and B, elgonica dimers A and B.
Leaves, pulp, and sap.
Dried juice from leaves.
Harvest mature leaves and rinse with water; remove spines prior
- There is confusing and contradicting information on edibility and reports on gastrointestinal cathartic effects. (see study and concerns below)
Aloe vera can be eaten, raw or cooked. The pale green skin hides the clear meat inside the leaves and its natural gel, both of which are edible. (32)
Jelly from matured leaves can be cut in small cubes, boiled with rock sugar for a sweetened cooling drink.
- Use for dandruff.
- Dried latex from leaf taken by mouth as laxative.
- Juice of fleshy leaves is usually mixed with gogo by Filipino women and used to prevent falling of fair or as a cure for baldness.
- Juice from leaves mixed with wine used to preserve the hair
- In the Philippines, leaves used to poultice edema associated with beriberi.
- Juice from leaves mixed with milk used for dysentery and pains of the kidney.
- Fresh juice expressed from the leaves is spread on skin burns, scalds,
scrapes, sunburn and wounds.
- Burns and scalds: Use ointment made by mixing equal amounts of powdered
aloe and coconut oil.
- Used for wound healing.
- For conjunctivitis, leaf juice is applied to the outer eyelid.
- Used for sprains, sore throat.
- In small doses, used as a tonic; in larger doses, as aperient; and in still larger doses, drastically so; it is also used as emmenagogue and cholagogue.
- In small doses, considered stomachic tonic; in large doses, as purgative.
- In Costa Rica, the mucilaginous pulp of leaves is used as purgative.
- For contusions or local edema, bruised fresh leaves are applied as poultice
over affected areas.
- For alopecia and falling hair, remove the spines, cut leaves and rub directly
on the scalp. The juice of fresh leave may be mixed with gogo and used
as a shampoo.
- Juice mixed with coconut milk used for dysentery and kidney pains.
- For bruises, equal parts of juice and alcohol are applied to affected
- For hemorrhoids, cuticle from leaves used as suppository for hemorrhoids.
- In India and the Antilles the alcoholic tincture of inspissated juice is used for bruises, contusions and ecchymoses.
- In the Arabian peninsula, used for diabetes.
- For burns and scalds, an ointment is prepared by mixing 2 drams of powdered aloe with 2 drams.
- Also used for herpes simplex sores, tendinitis, dandruff, menstrual cramps, acne, stomatitis, varicose veins, warts, hemorrhoids.
- Used in combination with licorice roots to treat eczema and psoriasis.
- In Ayurvedic medicine, used internally as laxative, anthelmintic, uterine stimulant and hemorrhoid treatment.
- Cosmetics: Plant materials derived from Aloe barbadensis (flower extract, leaf, leaf extract, leaf juice, leaf polysaccharides, leaf waters) are used as cosmetic ingredients for skin conditioning purposes, and included in cosmetics only at low concentrations. (see study below) (34)
Others: Benefits are derived from
a combination of all active components; the aqueous form provides the
- Leaf jelly used for various cosmetic and new-age concoctions for pimples, acne, stomatitis, hemorrhoidal itching, superficial burns. Aloe gel is a common household remedy for minor cuts, burns and sunburns.
- Salicylic acid content can inhibit prostaglandin and thromboxane formation
by blocking the arachidonic acid cascade.
- UV-B protection through cinnamic acid.
Concerns / Toxicities / Pros & Cons:
- Pros: Aloe vera can be eaten, raw or cooked. The pale green skin hides the clear meat inside the leaves and its natural gel (greenish goo-like), both of which are edible. (32) Aloe is likely safe when applied to the skin for burns, psoriasis, wound healing and to reduce pain and inflammation.
Cons: (1) Allergies - People with known allergy to other plants in the Liliaceae family (onions, garlic, tulips) may have allergic reactions to aloe.
Delayed allergic reactions - hives and rash - may develop with prolonged use.
(2) Aloe leaf consists of pericyclic cells, found just below the plant's skin and inner central area of the leaf, i.e., the gel, which is used in cosmetics. These cells produce a bitter, yellow latex containing anthraquinones, phototoxic compounds that are gastrointestinally irritating and responsible for its cathartic effects. (34)
- Chronic ingestion of whole leaf extracts should be limited and extracts low in anthraquinones and phenolics should be considered to reduce adenomas and adenocarcinomas of the large colon. (36)
Aloin / Contact Dermatitis / Laxative: The latex or juice (just below the outer skin) contains aloin, an anthraquinone glycoside, which has been reported to cause skin irritation or contact dermatitis in those with allergy to latex. The use of aloin latex as laxative may cause severe cramping and purging of the intestines; misuse can lead to electrolyte loss. (39)
- Pregnancy and Breastfeeding: While topical application is likely safe during pregnancy and lactation, internal use should be avoided. Theoretical stimulation of uterine contractions is a concern; likewise, the possibility that components of aloe may be excreted with breast milk. (15)
(1) Aloin is the presumed laxative component of aloe. Further studies are
needed to establish the dose and safety. (2) Anthraquinones in the latex considered to have potent laxative property, increasing intestinal water content, and stimulates mucus secretion and peristalsis.
• Radioprotective / Gamma and UV Exposure: Studies have reported a protective effect against radiation damage to the skin. It decreases the production and release of skin keratinocyte-derived immunosuppressive cytokines (IL-10), preventing UV-suppression of delayed type hypersensitivity.
• Genital Herpes:
Two randomized, double blind trials compared topical aloe vera cream (0.5% hydrophilic) or placebo three times daily for two weeks in 180 men with a first episode of genital herpes; one also assessed topical aloe vera gel. Response rates in the two trials were almost identical. The proportions of patients cured in the two trials were 70% and 67% with aloe vera cream, 45% with aloe vera gel, and 7.5% and 7.0% with placebo. Times to healing were 4.8 and 4.9 days with aloe vera cream, 7.0 days with aloe vera gel, and 14 and 12 days with placebo.(24)
• Psoriasis vulgaris:
(1) Evidence suggests aloe extract in hydrophilic creams to be of benefit
in psoriasis vulgaris. (2) One randomized double-blind trial assessed a 0.5% hydrophilic aloe vera cream compared with placebo cream in 60 patients with mild to moderate chronic plaque-type psoriasis over four weeks. The rate of cure was significantly better with aloe vera (83% ) than with placebo (7%) with no relapses. (24)
• Dandruff: Studies
suggest effectiveness for treatment of seborrheic dermatitis.
Study showed antigenotoxic potentials of aloe and suggests a potential
use in prevention of DNA damage caused by chemical agents. (2)
• Psoriasis vulgaris:
A double-blind placebo-controlled study to evaluate the efficacy and
tolerability of topical Aloe vera in a hydrophilic creams showed it
to be more effective than placebo without toxic or objective side effects
and can be considered a safe alternative treatment for psoriasis. (3)
• Anti-leukemic / Anti-Mutagenic:
Study isolated di(2-ethylhexyl)phthalate (DEHP) from Aloe vera. It exhibited growth inhibition against three leukemic cell lines and reduced AF-2-induced mutagenicity. DEHP was considered the active principle responsible for the anti-leukemic and anti-mutagenic effects in vitro. (4)
• Acemannan / Macrophage Activation: Study isolated a major carbohydrate fraction from the gel of Aloe vera leaf. It has been claimed to accelerate wound healing, immune stimulation and have anti-cancer and anti-viral effects. Study showed acemannan stimulate cytokine production, nitric oxide release. The production of cytokines IL-6 and TNF-alpha were acemannan dose-dependent. The results suggest acemannan may function, in part, through macrophage activation. (5)
• Aloeride / Immunostimulatory Activity: Study characterized a new immunostimulatory polysaccharide, Aloeride, from commercial aloe vera juice. (6)
• Aloe-emodin / Anticancer / Antiproliferative: Study showed aloe-emodin inhibited cell proliferation and induced apoptosis in two human liver cancer cell lines, but with different antiproliferative mechanisms. Results suggest aloe-emodin may be useful in liver cancer prevention. (7)
• Biochemotherapy: Study showed percentage of both objective tumor regressions and disease control was significantly higher in patients concomitantly treated with Aloe than with chemotherapy alone. Study suggest Aloe may be beneficial to use with chemotherapy to increase efficacy in terms of both tumor regression and survival time. (8)
• Antidiabetic: In a study of patients with non-insulin diabetes and Swiss albino mice with alloxan-induced diabetes, lowering of blood sugars was noted by as yet unknown mechanisms. (9)
• Increased Glucose Tolerance:In a study of 5 plants used by Kuwaiti diabetics, only extracts with myrrh and Aloe gums effectively increase glucose tolerance in both normal and diabetic rats.
• Burn Wound Healing: Based on meta-analysis using duration of wound healing as the outcome measure, the healing time of the aloe vera group was 8.79 days shorted than the control group. Cumulative evidence supports aloe vera as beneficial intervention for burn wound healing in first to second degree burns. (Some studies have shown contrary results, with one showing delayed healing. Also, the use of aloe on surgical wounds has been reported to slow healing. (11)
• Antimicrobial / Skin Infections: Study evaluated the antibacterial activity of leaf and gel extracts against gram positive and gram negative skin infections isolates. The gel extracts showed antibacterial activity against both gram positive and gram negative isolates. Leaf extracts showed no activity. (16)
• Photocarcinogenesis: Aloe vera is incorporated in many skin care/cosmetic products. Studies have suggested it may enhance the induction of skin cancer by ultraviolet radiation. This study found a weak enhancing effect of aloe vera leaf or decolorized whole leaf on the photocarcinogenic activity of SSL (simulated solar light) in both male and female mice. (17)
• Scabies: In a study of 16 patients treated with Aloe vera and 14 patients with benzyl benzoate lotion, the Aloe vera gel showed to be as effective as benzyl benzoate in the treatment of scabies. (18)
• Gastrointestinal Benefits: Study showed oral supplementation with Aloe vera reduced postprandial bloating, reduced flatulence, and improved colonic bacterial function. (20)
• Antiseptic: Aloe vera yields six antiseptic constituents -- lupeol, salicylic acid, urea nitrogen, cinnamonic acid, phenols, and sulfur -- with inhibitory effect on fungi, bacteria and viruses. (22)
• Antibacterial: Study showed the possibility of presence of bioactive components in crude extracts. Tested against E. coli, B. subtilis, S. typhi, Pseudomonas, K. pneumonia, S. epidermis, a methanol extract showed maximum antibacterial activity as compared to other solvent extracts. (23)
• Review of Clinical Effectiveness: Review concludes that event though there are promising results, clinical effectiveness of oral or topical aloe vera is not sufficiently defined at present. (24)
• Gastrointestinal Function in Normal Humans: Study showed Aloe vera juice supplementation in normal individuals was well tolerated, without covert or overt adverse effects on GI physiology. There was improved bowel motility, increased stool specific gravity, and reduced protein putrefaction in the colon. There was reduced postprandial bloating and reduced flatulence. (25)
• Oral Aloe vera for Treatment of Diabetes and Dyslipidemia: Review suggests a preponderance of evidence that suggests a trend toward benefit from oral aloe vera in reducing FBS and HbA1c. There was triglyceride reduction, but evidence for LDL, HDL, and total cholesterol are conflicting. Weaknesses in study methods and inconsistency in data do not currently warrant recommendation of oral aloe vera for the management of diabetes mellitus or dyslipidemia. (26)
• Antifungal: Study on the antifungal activity of different extracts of Aloe vera plant showed the acetone extract as an effective antifungal to inhibit growth of Aspergillus flavus. (27)
• Randomized Double-Blind Placebo-Controlled Trial on Irritable Bowel Syndrome: A randomized DB PC trial showed no overall benefit compared to patients on placebo. The study concludes AV is safe to take and could possible benefit patients with predominant diarrhea or the alternating diarrhea and constipation of IBS. (31)
• Safety Assessment: Aloe barbadensis derived ingredients were not toxic in acute oral studies using mice and rats. In parenteral studies, the LD50 in mice was >200 mg/kg, rats >50 mg/kg, and dogs >50 mg/kg. In intravenous studies the LD5- was mice>80 mg/kg rats > 15 mg/kg, and dogs >10 mg/kg.
In a 3-month study in mice, an alcohol extract given orally in drinking water at 100 mg/kg produced reproductive toxicity, inflammation and mortality above that seen in controls. A methanol extract given to mice at 100 mg/kg for 3 months caused significant sperm damage compared to controls. (34)
• Anthraquinone Content: The Cosmetic Ingredient Review Expert Panel concluded that the anthraquinone levels in several Aloe barbadensis extracts are well understood and can conform to the industry established level of 50 ppm. Although phototoxicity from anthraquinone components have been demonstrated, clinical studies have showed no phototoxicity, confirming the anthraquinone concentrations in such preparations are too low to induce toxicity.
• Aloe vera Water Studies / Carcinogenic Activity: A two-year study of a non-decolorized whole leaf extract of A. vera in drinking water found clear evidence of carcinogenic activity in male and female rats, based on tumors of the large intestine. There was no evidence of carcinogenic activity in male and female mice. Questions raised were: What products are in the market place? Aloin levels? Patterns of exposure?
• Cutaneous Wound Healing: A review on the effect of aloe vera on cutaneous wound healing concludes that aloe vera improves the wound healing in both clinical and experimental conditions. The use of aloe vera gel ethanolic extract attenuated the diabetic foot wound in rats. A clinical trial reported A. vera and Calendula ointment improved the speed of episiotomy wound healing. Review suggests considering Aloe vera treatment for improvement of wound healing is useful as well as other standard treatments.
• Hepatotoxicity: While animal studies suggest components of aloe vera
have hepatoprotective properties, at least a dozen cases of hepatotoxicity have been reported. Injury usually arises 3 to 24 weeks after starting oral aloe vera, usually taken in high doses for constipation, dyspepsia, aging and wellness. The pattern of injury is usually hepatocellular. None of aloe vera's leaf components are particularly hepatotoxic. Hepatotoxicity is rare and usually self-limiting. Severe cases are rare, and there have been no cases leading to fatalities, liver transplantation or chronic hepatitis.
Recurrent toxic hepatitis is likely from re-exposure. (39)
• Safety Profile: Review presents a safety profile: (1) Likely safe: Gel or extract applied topically to reduce pain and inflammation, enhance healing wounds, treat psoriasis, burns, frostbite injuries, herpetic cold sores. (2) Possibly safe: Short term oral use for potential hypoglycemic properties, or oral latex for short term use as laxative. (3) Likely unsafe: Prolonged laxative use because of potential dehydration and electrolyte imbalance. Topical use for postoperative wounds because of potential delay in wound healing. (41)
• Active Latex Constituents: Major C-glycosides, barbaloin and isobarbaloin, have been shown to be the principle agents responsible for the cathartic effects of A. vera latex. Both glycosides undergo large intestinal decomposition into active metabolites aloe-emodin-9-anthrone and aloe-emodin, which induces laxation via multiple mechanisms. (42)
• Animal Toxicity Studies: Aloe vera derived ingredients were not found to be toxic in acute oral studies in mice and rat models. In mice, LD50s were 200 mg/kg and 80 mg/kg in parenteral and intravenous studies, respectively; in rats, LD50 values were >50 mg/kg and >15 mg/kg, respectively. Lifelong Aloe vera ingestion in rats (1% of total diet) produced no harmful effects or deleterious changes. Chronic ingestion of 100 mg/kg Aloe vera (ethanol extract) in rats produced reproductive toxicity, as evidenced by significant sperm damage, inflammation and mortality compared to control. In a safety assessment study, the Cosmetic Ingredient Review Expert Panel (2007) concluded Aloe latex, not the polysaccharide material derived from inner gel, is cytotoxic. (43)
• Hypoglycemic: Study evaluated the an alcoholic extract for hypoglycemic activity on oral glucose-loaded rats and streptozotocin-induced diabetic rats. Results showed A. vera extract maintains glucose homeostasis by controlling the carbohydrate metabolizing enzymes. (43)
• Gastroesophageal Reflux: Pilot, randomized controlled trial investigated A. vera syrup for the treatment of gastroesophageal reflux disease (GERD).
Results showed A. vera was safe and well tolerated and reduced the frequencies of all assessed GERD symptoms (heartburn, food and acid regurgitation, flatulence, belching, dysphagia, nausea, vomiting). (44)
• Inhibition of Cytochrome P450 Substrates: Study evaluated the inhibitory potency of ethanol extracts of two commercially available aloe vera juice. One of the AVJ extracts showed twice the inhibitory potency towards both CYP enzymes (CYP3A4 and CYP2D6) with dual mechanistic inhibition (both CYP mediated and non-CYP mediated) which can affect the intracellular concentration of drugs metabolized by the enzymes. (29)
• Sevoflurane: Concomitant use with aloe vera may have additive antiplatelet effects to cause excessive bleeding during surgery. Sevoflurane inhibits thromboxane A(2) formation by suppression of cyclooxygenase activity, impairs platelet aggregation and prolongs bleeding. (28) (30)
• Other Drug Interactions: (1) Major interaction: By mouth, aloe latex may produce a laxative effect and decrease the body levels of potassium. A low potassium may increase the risk of side effects of digoxin (Lanoxin). Its laxative effect may further increase the stimulant effect of other laxative drugs: bisacodyl, senna, and others. (2) Moderate interactions: • Aloe may decrease blood sugar, and may further decrease blood sugar when taken with antidiabetic drugs. • Aloe may also decrease blood clotting, and use should be avoided for 2 weeks before any planned surgery. • By its laxative effect and intestinal potassium loss, aloe may exacerbate the low potassium effect of diuretics (water pills). (40)
- Ingredients to many commercial hair/cosmetic products.
- Gels, capsules, extracts in the cybermarket.