Written by Edzard Ernst and the CAM-Cancer Consortium.
Updated March 20, 2013

Aloe vera

Does it work?

This summary is currently (April 2016) being updated, the version published here was last updated in March 2013. 

Topical Aloe vera gel

Systematic reviews

Several clinical trials of topical Aloe vera gel to treat radiation-induced skin problems are available, and Richardson et al.10 have summarized their findings in a systematic review. The authors included seven RCTs. The quality of the studies and of reporting was frequently poor. Overall, the results failed to show the superiority of topical Aloe vera gel over various control treatments. The authors therefore concluded that “there is no evidence from clinical trials to suggest that topical Aloe vera is effective in preventing or minimising radiation-induced skin reactions in cancer patients”10.

A Cochrane review of various interventions to prevent mucositis in cancer patients included no further trials15. The authors did not draw a positive conclusion but felt that “there is a need for well-designed and conducted trials.”

Clinical trials

Since the publication of these reviews, several further trials have become available

Aloe vera gel was tested in an RCT with 57 head and neck cancer patients undergoing radiotherapy 16. The experimental group received topical aloe vera gel daily until one month after the completion of readiotherapy plus standard care; the control group had standard care only. The results demonstrated that there were a significantly delayed onset of skin reaction and low percentage of patients with severe radiotherapy induced skin reactions in the experimental group as compared to control group. At one month post radiotherapy there was no significant difference between two groups for radiotherapy induced skin reactions. During the later course of radiotherapy (at 6th /7th week) significant difference between two groups for pain scores was seen. However there was no significant difference in the two groups in the occurrence of radiation induced skin reaction related complications the authors conclude that aloe vera gel was effective in delaying the onset and reducing the severity of radiation induced skin reactions during the course of radiotherapy.

Another trial tested aloe vera gel for oral submucosal fibrosis (OSMF), a potentially malignant disorder of the oral mucosa, frequently associated with chewing gutka and betel quid 17. Twenty study subjects with OSMF were included in the study. Patients were randomised into two groups; group A received 5 mg of aloe vera gel to be applied topically three times daily for 3 months. Group B subjects received antioxidant capsules twice daily for 3 months. The results showed that aloe vera patients responded better in terms of symptoms and early-stage histopathology. Aloe vera generated a statistically significant relative reduction in burning sensation, improvement in mouth opening, and cheek flexibility.

Oral Aloe vera

Clinical trials

The effectiveness of oral Aloe vera products are less well studied. Lissoni et al.12 treated 50 patients with advanced mixed cancers either with melatonin or with melatonin plus Aloe vera tincture (1ml, 2x/day). A partial response was seen in no patient from the former and two patients from the latter group. These findings are preliminary at best.

Su et al.11 randomised 58 head and neck cancer patients to receive either Aloe vera (20ml juice) or placebo in addition to usual care. The results show no statistically significant inter-group differences in terms of quality of life, mucositis, pain, weight loss and other endpoints.

Lissoni et al.18 randomised 240 patients with mixed metastic solid tumours into receiving either chemotherapy or chemotherapy plus Aloe vera (extract of 300g fresh leaves 3x/day). The results indicated that tumour regression, 3-year survival times and subjective symptoms were both better in the latter group. This study seems well-conducted and its results are encouraging. However, independent replication seems necessary.

Puataweepong et al.19 conducted an RCT with 61 head and neck cancer patients who received either Aloe vera juice or placebo in addition to usual care. The endpoint was mucosal reaction to radiation therapy. The incidence of severe mucositis was 53% in the Aloe vera group and 87% in the placebo group. No difference was noted in the duration of mucositis, however.

The notion that oral Aloe vera might prevent lung cancer was supported by a Japanese case-control study20. A comparison of 44 pairs was analysed according to plant food intake. The results suggested that those study participants regularly consuming Aloe vera were associated with a reduced lung cancer-risk. Even though interesting, this small study cannot prove that the detected association is causal.

Citation Edzard Ernst, CAM-Cancer Consortium. Aloe vera [online document]. http://ws.cam-cancer.org/The-Summaries/Herbal-products/Aloe-vera. March 20, 2013.


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