Four out of 10 U.S. adults used complementary and alternative medicine in 2007, as reported by the National Center for Complementary and Alternative Medicine. That same year, 18 percent of adults took non-vitamin, non-mineral natural products such as aloe vera. Limited scientific evidence exists for the use of aloe to treat disease. Moreover, the National Institutes of Health is concerned that chronic high-dose ingestion of aloe vera may induce liver inflammation.

Aloe Vera

Aloe vera is native to Africa and commercially cultivated all over the world. The spiky succulent plant is a source of vitamins, minerals, sugars, enzymes and amino acids, as outlined in the British Journal of General Practice. According to the NIH, there is good evidence for the alleviation of short-term constipation through aloe ingestion. The evidence, however, is unclear for the use of aloe in diabetes, ulcerative colitis and cancer prevention.

The Liver

Situated in the right-upper quadrant of the abdomen, just below the diaphragm, the liver is the largest solid organ in your body. As related by the British Liver Trust, the reddish-brown gland performs over 500 important functions. In addition to making proteins and enzymes for chemical reactions, it removes toxins from the blood and regulates hormones. The food you eat is digested by bile made in the liver and converted into energy. Energy that isn’t used quickly is stored in this vital organ for use during fasting states, like sleeping. The liver also plays a critical role in immune defense.

Evidence

In a 2005 article in the “World Journal of Gastroenterology,” German researchers reported on a 57-year-old woman who presented with severe acute hepatitis after taking aloe vera capsules for four weeks. Her symptoms resolved after discontinuing the supplement.A similar case occurred in the U.S., as described in 2007 in the “Annals of Pharmacotherapy.” Acute hepatitis symptoms abated after a 73-year-old woman discontinued aloe vera supplementation. “Journal of Korean Medical Science,” in 2008, also published a case report. When a 62-year-old woman stopped taking aloe extract, her severe hepatitis resolved.

Mechanism of Action

The German authors attributed the onset of liver inflammation to bioactive compounds in the aloe vera plant. Alkaloids in aloe may affect liver enzyme systems in people with hypersensitivity, interfering with the liver’s detoxification function. Phytochemicals present in aloe may also trigger an immune response that damages the liver. Hypersensitivity to aloe vera was described in humans as early as 1980. An allergic skin test may determine whether you are hypersensitive to aloe.

Safety

The NIH maintains that taking aloe vera for less than seven days to alleviate occasional constipation is safe, although no specific dose has been determined. Evidence supports safe topical use of aloe for psoriasis, seborrheic dermatitis and genital herpes. Cases of acute hepatitis have been reported after as little as four weeks of aloe ingestion. Tell your doctor about everything you take, including herbal supplements.