Aloe vera: gel on skin, latex laxatives, oral supplements and liver concerns

The gel is the translucent jelly found in the centre of the leaf and is the ingredient in most after-sun lotions. Aloe latex is a yellow, bitter fluid found just beneath the leaf skin and contains anthraquinone compounds that stimulate the bowel. Whole-leaf extract can contain both. Safety and evidence differ for each, and a pack that does not say which one it holds is hard to judge.

Evidence for skin use is modest but real. The NCCIH reports that aloe gel applied to the skin may speed burn healing and reduce burn-related pain, and may help acne. Limited evidence also suggests possible benefit for psoriasis, herpes sores and lichen planus. Most people tolerate gel well, though some get burning, itching or a rash.

None of this makes aloe a first-aid treatment for a new burn. The NHS advice is to hold a burn or scald under cool running water for twenty minutes, as soon as possible and within three hours, then cover loosely with cling film. It says not to apply creams, oils or butter to the burn. Aloe belongs in the later, healing phase of a minor sunburn or superficial injury, not on a fresh burn.

• Call 999 or go to A&E for a very large or deep burn, a burn on the face, genitals or bottom, or one caused by acid, chemicals or electricity.

• A pharmacist can suggest emollient ointments once a small burn is healing and itchy.

Oral aloe latex is a stimulant laxative, and it can cause abdominal pain, cramps and diarrhoea. In 2002 the US regulator removed aloe latex from over-the-counter laxatives because of safety concerns. Chronic laxative use is a recognised cause of potassium loss, and overuse of aloe may amplify risks from cardiac glycosides such as digoxin, which are sensitive to potassium levels.

Aloe leaf extracts taken by mouth have been associated with cases of acute hepatitis. The International Agency for Research on Cancer has classified whole-leaf aloe extract as a possible carcinogen. Persistent constipation deserves medical assessment rather than regular aloe laxatives, and yellowing of the skin or eyes after starting a supplement should prompt urgent advice.

Some small studies suggest oral aloe may lower blood sugar in people with diabetes and reduce weight modestly in people who are overweight, but the evidence is preliminary. Anyone on insulin or tablets for diabetes who adds aloe could in theory drop their glucose further, so they should tell the diabetes team. Aloe juice is sold as a health drink, and the amount of latex-derived compounds varies by processing.

Aloe taken by mouth may be unsafe during pregnancy and while breastfeeding. The NHS advises against herbal medicines in those situations and for children. Gel on small patches of skin is less of a concern, but sensitive or broken skin may react.

In the UK, aloe gels are normally cosmetics, while drinks and capsules are food supplements. Neither is assessed as a medicine, and the MHRA has noted that most herbal products on the market are unlicensed with variable quality. The NHS recommends checking with a pharmacist before taking a herbal medicine if you already take prescribed medicines.