Aloe vera has been used medicinally for thousands of years, and I find it genuinely fascinating how this succulent plant has maintained its reputation across so many different cultures. The ancient Egyptians called it the “plant of immortality,” while traditional Chinese and Ayurvedic practitioners have long valued it for various therapeutic applications. But what does modern research actually tell us about aloe vera’s benefits and risks?

I should note upfront that aloe vera products come in two distinct forms with very different safety profiles: the clear gel from inside the leaves, and the yellow latex found just beneath the outer skin. This distinction matters enormously when evaluating the evidence, so I’ll be clear throughout this article about which form the research addresses.

What’s actually in aloe vera?

The gel portion of aloe vera leaves is roughly 99% water, with the remaining 1% containing polysaccharides (particularly acemannan), amino acids, vitamins A, C, and E, minerals including zinc and magnesium, and various enzymes [1]. The latex portion contains anthraquinones, most notably aloin, which gives it laxative properties.

I think it’s worth mentioning that the specific composition varies considerably depending on the species, growing conditions, and processing methods. This variability makes it challenging to compare studies that use different aloe vera preparations.

7 evidence-based benefits of aloe vera

1. May support periodontal health

Periodontal disease affects the tissues supporting your teeth, and severe cases can lead to tooth loss. While mechanical cleaning remains the standard treatment, researchers have explored various adjunctive therapies.

A 2021 systematic review and meta-analysis examined 13 randomised controlled trials comparing aloe vera products (gels, mouthwashes, and toothpastes) against other treatments including chlorhexidine and triclosan [2]. The reviewers found that aloe vera formulations improved periodontal parameters such as plaque index and gingival inflammation scores.

My reading of this evidence: the results look promising, but the studies used different aloe vera preparations and treatment protocols. I’d say aloe vera-containing oral care products might offer modest benefits as an adjunct to regular dental hygiene, not as a replacement for professional care.

2. May help oral lichen planus

Oral lichen planus is a chronic inflammatory condition affecting the mouth lining, tongue, and gums. It occurs in about 1-2% of the general population, predominantly in women over 40.

A 2017 meta-analysis of seven studies found that while corticosteroids remain the first-line treatment, aloe vera performed reasonably well with fewer reported side effects [3]. The authors noted that aloe vera might be particularly useful for patients who cannot tolerate or prefer to avoid steroid-based treatments.

I find this application interesting because oral lichen planus can be persistent and uncomfortable. However, the evidence base remains limited, and I’d encourage anyone with this condition to discuss treatment options with their dentist or oral medicine specialist.

3. May help with irritable bowel syndrome

Irritable bowel syndrome (IBS) affects roughly 11% of the global population and involves chronic abdominal pain alongside altered bowel habits. Researchers believe gut microbiome changes, low-grade inflammation, and visceral hypersensitivity all play roles.

A 2018 systematic review and meta-analysis pooled data from three randomised controlled trials involving 151 IBS patients [4]. The analysis found statistically significant improvements in symptom scores and treatment response rates compared to placebo. Interestingly, subgroup analysis suggested that shorter treatment periods (one month) showed more pronounced effects than longer courses.

I should be honest here: three trials with 151 total participants is a modest evidence base. The results are encouraging but far from definitive. If you have IBS, aloe vera might be worth discussing with your gastroenterologist, but don’t expect miraculous results.

4. Mixed results for psoriasis

Psoriasis is a chronic inflammatory skin condition affecting 1-3% of people worldwide, characterised by raised, scaly patches. Because standard treatments don’t work for everyone, researchers have tested various plant extracts.

A 2017 systematic review examined four clinical studies of aloe vera for psoriasis [5]. Unfortunately, the results were inconsistent. Some trials showed benefit whilst others did not, and the review concluded that aloe vera cannot currently be recommended as a therapeutic option for psoriasis.

I appreciate that researchers were willing to publish this inconclusive finding. It’s a useful reminder that traditional use doesn’t always translate into proven clinical benefit.

5. Uncertain effects on wound healing

The skin’s ability to repair itself after injury is remarkable, but sometimes wounds need additional support, particularly when dealing with burns, ulcers, or extensive tissue loss.

A Cochrane systematic review evaluated seven randomised controlled trials involving 347 participants with various wound types [6]. The reviewers examined aloe vera dressings and gels for both acute wounds (burns, surgical incisions) and chronic wounds (ulcers, infected wounds). The verdict? Both positive and negative findings, with no clear consensus.

This surprised me somewhat, given aloe vera’s long traditional use for burns and skin injuries. The evidence simply doesn’t yet support recommending it over established wound care approaches, though it’s also not shown to be harmful when used topically.

6. May lower blood sugar

With diabetes affecting hundreds of millions globally and many patients seeking complementary approaches, researchers have investigated aloe vera’s effects on glycaemic control.

A 2016 meta-analysis of eight studies involving 480 participants found that oral aloe vera supplementation reduced fasting blood glucose and HbA1c levels in people with prediabetes and type 2 diabetes [7]. The NHS notes that while some preliminary research suggests aloe vera may help lower blood sugar, more high-quality studies are needed before it can be recommended [8].

I think it’s important to emphasise that aloe vera should never replace prescribed diabetes medications. The blood sugar-lowering effects, if real, also mean diabetics need to be cautious about hypoglycaemia risk when using aloe vera supplements.

7. May enhance acne treatment when combined with retinoids

Acne affects up to 85% of people aged 11-30 at some point, primarily on the face, chest, and back. The condition involves increased sebum production, abnormal keratinisation, bacterial overgrowth, and inflammation.

An eight-week randomised controlled trial with 60 patients compared topical tretinoin (vitamin A acid) alone versus tretinoin combined with aloe vera gel [9]. The combination therapy produced significantly better improvements in both inflammatory and non-inflammatory acne lesions.

This makes intuitive sense to me, as aloe vera’s anti-inflammatory and moisturising properties might help offset some of tretinoin’s irritating effects. If you’re using retinoids for acne, asking your dermatologist about adding aloe vera gel could be worthwhile.

Side effects of aloe vera

The side effect profile differs quite a bit between topical gel and oral preparations.

Topical aloe vera gel is generally well-tolerated, but some people experience contact dermatitis with symptoms including redness, burning sensations, and rashes. Those with sensitive skin or existing skin conditions should patch-test before widespread use. Importantly, aloe gel should not be applied to open wounds or deep cuts.

Oral aloe vera carries more significant risks, particularly products containing aloe latex. Reported side effects include:

Abdominal cramps and diarrhoea (sometimes severe)
Dark-coloured urine
Electrolyte imbalances, particularly low potassium
Hepatotoxicity (liver damage) in some case reports
Kidney dysfunction with prolonged use
Muscle weakness

The Mayo Clinic advises that oral aloe vera products containing aloe latex are “likely unsafe” when taken in high doses [10]. Long-term use of aloe latex can also cause dependency, requiring increasing doses to achieve the same laxative effect.

8 safety precautions and contraindications

Here are the precautions I’d highlight:

Pregnancy: Oral aloe vera may stimulate uterine contractions and has been associated with increased miscarriage risk. Pregnant women should avoid oral aloe vera products entirely.
Breastfeeding and children: Safety data are insufficient. I’d recommend avoiding oral preparations in these groups.
Lily family allergies: Aloe vera belongs to the Liliaceae family. If you’re allergic to garlic, onions, tulips, or other lily family plants, you may react to aloe vera as well.
Pre-surgical period: Discontinue oral aloe vera at least two weeks before any scheduled surgery due to potential bleeding and blood sugar effects.
Diabetes medications: Aloe vera may enhance blood sugar-lowering effects, increasing hypoglycaemia risk. Monitor blood glucose carefully and inform your healthcare provider.
Inflammatory bowel conditions: People with Crohn’s disease, ulcerative colitis, or interstitial cystitis should avoid oral aloe latex, which can irritate the gut lining and potentially trigger flares.
Haemorrhoids: Oral aloe latex may worsen haemorrhoid symptoms due to its irritant laxative properties.
Drug interactions: Aloe vera may interact with diuretics (increasing potassium depletion), cardiac glycosides like digoxin, other laxatives, anticoagulants such as warfarin, and diabetes medications. Discuss with your pharmacist if you take any regular medications.

The bottom line

Aloe vera has been used medicinally for thousands of years, and there’s some scientific support for that reputation, but the evidence remains modest for most claimed benefits. Topical aloe vera gel appears reasonably safe for most people and may offer benefits for acne treatment and oral health. Oral preparations, particularly those containing aloe latex, carry more significant risks and require careful consideration.

I’d suggest treating aloe vera as a potentially useful complementary approach rather than a first-line treatment for any condition. Always inform your healthcare providers about any supplements you’re taking, and be particularly cautious if you have chronic bladder conditions, frequent urination, or digestive disorders.

References

Surjushe A, Vasani R, Saple DG. Aloe vera: a short review. Indian J Dermatol. 2008;53(4):163-166.
Gupta R, et al. Aloe vera in dentistry: A systematic review and meta-analysis. J Indian Soc Periodontol. 2021;25(5):371-380. PubMed
Ali S, Wahbi W. The efficacy of aloe vera in management of oral lichen planus: a systematic review and meta-analysis. Oral Dis. 2017;23(7):913-918. PubMed
Hong SW, et al. Aloe vera is effective and safe in short-term treatment of irritable bowel syndrome: A systematic review and meta-analysis. J Neurogastroenterol Motil. 2018;24(4):528-535. PubMed
Lowe H, et al. The therapeutic potential of aloe vera in psoriasis: a systematic review. J Am Acad Dermatol. 2017;76(6):AB68. PubMed
Dat AD, et al. Aloe vera for treating acute and chronic wounds. Cochrane Database Syst Rev. 2012;(2):CD008762. PubMed
Zhang Y, et al. Efficacy of aloe vera supplementation on prediabetes and early non-treated diabetic patients: a systematic review and meta-analysis. Nutrients. 2016;8(7):388. PubMed
NHS. Aloe vera. Available at: https://www.nhs.uk/conditions/complementary-and-alternative-medicine/aloe-vera/
Hajheydari Z, et al. Effect of Aloe vera topical gel combined with tretinoin in treatment of mild and moderate acne vulgaris. J Dermatolog Treat. 2014;25(2):123-129. PubMed
Mayo Clinic. Aloe. Available at: https://www.mayoclinic.org/drugs-supplements-aloe/art-20362267