Aloe vera is considered the "plant of immortality". The natural remedy, known since ancient times, has had an impressive career. Is now considered "health food landed in the vegetable counters. Incorrectly prepared, however, it is a plant of mortality.
The Stuttgart food monitoring agency – almost at the same time as Stiftung Warentest – has taken up the cause of a so-called "miracle plant" accepted, even as a "plant of immortality is advertised: the Aloe vera. Apparently the food trade could not resist either. Took the fleshy leaves into the assortment of its fresh vegetables. Unfortunately, the leaves contain toxic anthraquinones, which must be carefully removed before consumption.
Edible is namely only the gel-like leaf interior, that is the water reservoir of the desert plant. The yellow, bitter secretion, which is secreted by a kind of latex layer between the green leaf bark and the pith, is quite problematic. Therefore the leaves must be peeled. The gel should be rinsed thoroughly with water before consumption. This is also the advice given in the package leaflet.
Renaissance as a natural remedy
Aloe vera has long been used folk medicine, externally for burns and internally for constipation and to combat worms in the intestine. Mothers have also brushed the fingers of their children with the bitter bile extract to discourage them from sucking their thumbs. In the 1930s, aloe gels were first used clinically to relieve burns caused by racial radiation treatments.
Today, aloe is experiencing a renaissance as a natural remedy. In addition to burns and blockages, it should first be useful for gastrointestinal ulcers and diabetes. But in the meantime, the advertising hardly leaves out a disease. In the south of the USA, an entire industry has formed that cultivates aloe using state-of-the-art methods and markets it globally. Stiftung Warentest, however, judges – in line with experts – that the claimed effects are mostly not substantiated by clinical studies.
Banned in packaging
Strict restrictions on medicines containing anthraquinones were imposed in Germany as early as 1999, and pharmacies were required to sell them. The Federal Institute for Drugs and Medical Devices recommends not to exceed the daily intake of 30 mg of these toxins and not to use the preparations for more than one to two weeks. Anthraquinones are feared as harmful substances. That's why the Federal Institute for Risk Assessment banned their use in packaging in 2013 – because they could end up in food in trace amounts. For the food itself is still missing appropriate regulations for the protection of the consumer.
The most harmless side effect of aloe is probably diarrhea, which can sometimes be of resounding severity, and phototoxic reactions of the skin; more risky are disturbances of cardiac function, kidney failure and liver inflammation. Pregnant women are warned against consumption. In addition, the plant is classified as carcinogenic by the relevant professional organizations. Undeterred, nutrition websites recommend using the bitter parts of the peel as well – especially for making smoothies. The madness!
Vegetables with package insert
A test by the Chemical and Veterinary Investigation Office in Stuttgart shows that even if the preparation instructions are scrupulously observed, there is a risk that "high amounts of toxicologically questionable substances from the anthraquinone class may enter the ready-to-eat leaf gel. Even when the correct procedure was followed, the limit value applicable to medicinal products was exceeded. The authority therefore expressly warns against self-preparation.
The situation looks better for industrially manufactured products. According to the results of the Stuttgarter, their toxin levels are lower by a factor of 300 than in the case of self-preparation. It remains to be seen whether this can be attributed in individual cases to the economical use of the raw material or to meticulous control of the anthraquinone content in the finished product. No matter how – a dubious medicinal plant has no place at all on the vegetable shelves of our supermarkets. Not even with package inserts. Meal!
Lerch C et al: Aloe leaves – Self-preparation of aloe gel in the home carries risks. CVUA Stuttgart, report from 27.04.2017
Paez A et al: Growth, soluble carbohydrates, and aloin concentration of Aloe vera plants exposed to three irradiance levels. Environmental& Experimental Botany 2000; 44: 133-139
Boudreau MD et al: Clear evidence and carcinogenic activity by a whole-leaf extract of Aloe barbadensis (Aloe vera) in F344/N rats. Toxicological Sciences 2013; 131: 26-39
Lee J et al: Acute toxic hepatitis caused by an Aloe vera preparation in a young patient: a case report with a literature review. Korean Journal of Gastroenterology 2014; 64: 54-58
Ramachandra CT et al: Processing of Aloe vera leaf gel: A Review. American Journal of Agricultural& Biological Sciences 2008; 3: 502-510
EFSA: Scientific Opinion on the substantiation of a health claim related to hydroxyanthracene derivatives and improvement of bowel function pursuant to Article 13(5) of Regulation (EC) No 1924/20061 EFSA Journal 2013; 11: e3412
BfR: BfR deletes anthraquinone from the BfR recommendations for food packaging. Statement No.