Aloe vera has many medicinal uses

Asthma and arthritis are just some of the diverse ailments that aloe vera can help says Sarah Stacey and Dr Chris Brown

The long spiky grey green leaves of aloe vera, edged with tiny prickles, look as if it comes from the cactus family. In fact, this long respected medicinal plant, with its spear of yellow or orange flowers, is a type of lily. The leaves provide the clear aloe gel that Cleopatra is said to have used on her famously luscious skin, and the yellow sap that comes from the base of the dried leaf is known as bitter aloes.

Aloe almost certainly originated in the eastern and southern regions of Africa. Because of its long history as a useful medicinal plant, it has been the companion of travellers throughout the centuries and is now found in warm climates worldwide. It's easy to grow at home in a pot and is remarkably tolerant, although it needs sun and doesn't do well if it gets waterlogged.

Aloe has been used medicinally for as long as recorded history, both externally and internally. There are records of it on Sumerian clay tablets as early as 2,200 BC. The great Roman pharmacologist Dioscorides (41-68 AD), who travelled with the army, gave the first detailed description. He described its power to induce sleep, loosen the belly, heal bruises and mouth irritations, cleanse the stomach, ease haemorrhoids and salve boils. What's more, he added that the whole leaf when pulverised could stop wounds from bleeding.

Fascinatingly, it's used in much the same way today. One of aloe's key uses is as a topical treatment for skin conditions. In the 1930s and 40s, extensive research in the UK and the former Soviet Union demonstrated that aloe gel applied topically has a significant ability to heal wounds, ulcers and burns by sealing the damaged flesh with a protective coat and speeding up the rate of healing. Researchers believe that this is partly due to a compound called aloectin B that stimulates the immune system and thus promotes healing. Aloe is also used in several ranges of beauty products.