Aloe Vera
Summary
Aloe vera supplements come from the inner-leaf gel, the outer latex or the whole leaf. Small trials suggest modest blood sugar benefits in type 2 diabetes and short-term IBS relief, but the largest IBS trial was null (grade C at best). Latex was removed from US laxatives, non-decolorized whole-leaf extract caused intestinal tumors in rodents, and liver injury has been reported.
Key facts
- Inner-leaf gel, outer-leaf latex (laxative anthraquinones) and whole crushed leaf, which contains both[1]
- Across 8 RCTs (470 people), HbA1c fell about 11 mmol/mol in type 2 diabetes; trials were small and varied[6]
- A 3-trial meta-analysis found short-term benefit, but the largest trial (160 people) found no difference from an inulin control[3][4]
- In 2002 the FDA required aloe latex to be removed from over-the-counter laxatives for lack of safety data[1]
- IARC lists non-decolorized whole-leaf extract as a possible human carcinogen; it caused intestinal tumors in 2-year rodent studies[1][8]
- 6 graded human outcomes on this page
- October 13, 2026
How it works
ProposedThe latex contains anthraquinones such as aloin, which act as stimulant laxatives. Gel polysaccharides are proposed to have prebiotic and glucose-lowering effects, but how oral gel might change blood sugar in people has not been established.[1][4]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Blood sugar | Grade C | Improved | Meta-analysis of 8 trials · n = 470 · 2016 | 1 row |
| IBS | Grade C | No effect | RCT · n = 160 · 2020 | 4 rows |
| Ulcerative colitis | Grade D | Improved | RCT · n = 44 · 2004 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Fasting glucose and HbA1c in prediabetes and type 2 diabetes | Improved | Grade C | Meta-analysis · n = 470 · 2016 Adults with prediabetes or type 2 diabetes (8 RCTs) Form: Various oral aloe vera preparations · Dose: Varied across trials · Duration: Varied across trials Prediabetes: fasting glucose fell 0.22 mmol/L with no HbA1c change. Type 2 diabetes: HbA1c fell 11 mmol/mol (about 1 percentage point) and fasting glucose fell marginally (P=0.05). Heterogeneity was high. | 27009750 (opens PubMed)Source [6] |
| IBS symptom severity vs an inulin control | No effect | Grade C | RCT · n = 160 · 2020 Adults with IBS, all subtypes (Sweden) Form: Aloe barbadensis extract · Dose: Dose not stated in the abstract · Duration: 4 weeks Symptoms fell in both groups with no difference between aloe and inulin (P=0.62); responders 39% vs 45%. | 32314514 (opens PubMed)Source [4] |
| IBS symptom scores and response rate | Improved | Grade C | Meta-analysis · n = 151 · 2018 Adults with irritable bowel syndrome (3 RCTs) Form: Aloe vera juice or extract tablets · Dose: 50 mL four times daily, 60 mL twice daily, or one tablet twice daily (per included trial) · Duration: 4 weeks to 5 months Symptom scores improved more than placebo (SMD 0.41) and response rates were higher (RR 1.69); no aloe-related adverse events were reported. The benefit was seen at 1 month but not beyond 3 months. | 30153721 (opens PubMed)Source [3] |
| IBS responders and symptom severity (AVH200) | No effect | Grade D | Pilot RCT · n = 68 · 2015 Adults with IBS by Rome III criteria (Sweden) Form: Aloe barbadensis extract tablets (AVH200) · Dose: One tablet twice daily · Duration: 4 weeks The primary endpoint was not met: 55% vs 31% responders (P=0.09) and no significant between-group difference in symptom severity (P=0.10). | 26405698 (opens PubMed)Source [5] |
| IBS response in refractory patients | No effect | Grade D | RCT · n = 58 · 2006 Secondary-care patients with refractory IBS (UK) Form: Aloe vera juice · Dose: 50 mL four times daily · Duration: 1 month (follow-up to 3 months) Response at 1 month was 35% with aloe vs 22% with placebo (P=0.763); diarrhoea-predominant patients showed a non-significant trend. | 16749917 (opens PubMed)Source [2] |
| Clinical response in active ulcerative colitis | Improved | Grade D | RCT · n = 44 · 2004 Outpatients with mildly to moderately active ulcerative colitis (UK) Form: Oral aloe vera gel · Dose: 100 mL twice daily · Duration: 4 weeks Clinical response occurred in 47% on aloe vs 14% on placebo (P<0.05); remission (30% vs 7%) was not significant. Sigmoidoscopy scores and lab values did not differ. | 15043514 (opens PubMed)Source [7] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Inner-leaf gel or juice (decolorized) | Varies[1] | No head-to-head human absorption data.[1] | Short-term oral gel use (up to 42 days) appears safe in studies; adverse events were minor and similar to placebo in the ulcerative colitis trial.[1][7] | IBS, ulcerative colitis and blood sugar trials |
| Standardized Aloe barbadensis extract tablets (AVH200) | Varies[5] | No head-to-head human absorption data.[5] | Well tolerated with no serious adverse events in the 4-week pilot trial.[5] | IBS trials |
| Aloe latex (outer leaf, anthraquinones) | Varies[1] | Acts in the gut as a stimulant laxative.[1] | Can cause abdominal pain, cramps and diarrhea; removed from US over-the-counter laxatives in 2002.[1] | Historic laxative use; not tested in the trials on this page |
| Non-decolorized whole-leaf extract | Varies[8] | No human absorption data.[8] | Caused intestinal tumors in 2-year National Toxicology Program rodent studies; not commonly sold to consumers.[1][8] | Rodent toxicity studies only |
Studied doses
Doses studied in human trials ranged from one extract tablet twice daily to 200 mL of aloe juice or gel per day (50 mL four times daily, or 100 mL twice daily), for 4 weeks up to about 5 months. Glucose trials used varied preparations that the pooled analysis did not standardize.[3][5][6][7]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Medicines
- Cardiac glycosidesNIH fact sheetOveruse of aloe latex may increase the risk of adverse effects from cardiac glycosides.[1]
Who should be careful
- Pregnancy and breastfeeding
- NCCIH says aloe gel, latex or whole-leaf extract taken by mouth may be unsafe during pregnancy and breastfeeding.[1]
- Liver problems
- Oral aloe leaf preparations, used for 3 weeks to 5 years, have been linked to cases of acute hepatitis that resolved after stopping.[1][9]
- Laxative-type products
- Aloe latex can cause cramps and diarrhea and was removed from US over-the-counter laxatives.[1]
- Diabetes medicines
- Pooled trials showed lower fasting glucose and HbA1c with oral aloe, which matters for people whose glucose-lowering medicines are dosed to their readings.[6]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
How to read the label
- Check which part of the leafInner-leaf gel, latex and whole-leaf products are different. Latex and non-decolorized whole leaf carry the laxative and rodent-tumor concerns.[1][8]
- DecolorizedDecolorized whole-leaf extract has been filtered through activated carbon to remove anthraquinones; a 2023 review of drinks with no more than 10 ppm aloin found no genotoxicity, although NCCIH notes a small amount of lab research suggesting even decolorized extract might damage DNA.[1]
- Label dose vs studied doseTrials dosed juice by volume (for example 50 mL four times daily) rather than milligrams, so a capsule's mg amount cannot be matched to a studied dose.[3][7]
Frequently asked questions
Does drinking aloe vera help IBS?
Possibly short term, but the evidence is weak. Three small trials pooled showed benefit at 1 month; the largest trial (160 people) found aloe no better than inulin.[3][4]
Does aloe vera lower blood sugar?
Small trials suggest it may. Pooled across 8 trials, HbA1c fell about 11 mmol/mol in type 2 diabetes and fasting glucose fell slightly in prediabetes, with high variation between trials.[6]
Is aloe vera a laxative?
The outer-leaf latex is. It contains anthraquinones, can cause cramps and diarrhea, and was removed from US over-the-counter laxatives in 2002.[1]
Can aloe vera harm the liver?
Cases of acute hepatitis have been reported after weeks to years of oral aloe leaf products; liver tests returned to normal after stopping.[1][9]
Does aloe vera cause cancer?
Non-decolorized whole-leaf extract caused intestinal tumors in rats and mice, and IARC lists it as a possible human carcinogen. That form is not commonly sold; a 2023 review found decolorized drinks not genotoxic, though a little lab research suggests decolorized extract might still damage DNA.[1][8]
Does aloe vera help ulcerative colitis?
One 44-person trial found more clinical responses with 100 mL of gel twice daily for 4 weeks, but remission and sigmoidoscopy scores did not differ significantly from placebo.[7]
Sources
- [1]Aloe Vera: Usefulness and Safety. NIH National Center for Complementary and Integrative Health, 2025. fact-sheet
- [2]Randomised double-blind placebo-controlled trial of aloe vera for irritable bowel syndrome.. Int J Clin Pract, 2006. RCT
- [3]Aloe vera Is Effective and Safe in Short-term Treatment of Irritable Bowel Syndrome: A Systematic Review and Meta-analysis.. J Neurogastroenterol Motil, 2018. meta-analysis
- [4]Randomized clinical trial: Effects of Aloe barbadensis Mill. extract on symptoms, fecal microbiota and fecal metabolite profiles in patients with irritable bowel syndrome.. Neurogastroenterol Motil, 2020. RCT
- [5]A Pilot Study of the Effect of Aloe barbadensis Mill. Extract (AVH200®) in Patients with Irritable Bowel Syndrome: a Randomized, Double-Blind, Placebo-Controlled Study.. J Gastrointestin Liver Dis, 2015. pilot-RCT
- [6]Effect of Aloe vera on glycaemic control in prediabetes and type 2 diabetes: a systematic review and meta-analysis.. J Clin Pharm Ther, 2016. meta-analysis
- [7]Randomized, double-blind, placebo-controlled trial of oral aloe vera gel for active ulcerative colitis.. Aliment Pharmacol Ther, 2004. RCT
- [8]The toxicity and pathology of selected dietary herbal medicines.. Toxicol Pathol, 2013. review
- [9]Aloe-induced toxic hepatitis.. J Korean Med Sci, 2010. observational
What changed
- Independent review: added NCCIH caveat that limited lab research suggests decolorized extract might damage DNA, alongside the 2023 no-genotoxicity review. All PMIDs re-checked.
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows. Davis 2006 and Størsrud 2015 regimens and the IBS 1-month vs 3-month subgroup taken from the 2018 meta-analysis full text (PubMed 30153721, PMC full text). NCCIH aloe fact sheet (updated February 2025) read for safety, the 2002 FDA laxative ruling and the IARC classification. Page set indexable.