It's trendy but expensive, so make your own kombucha

The advertising campaign with Susan Sarandon, the Hollywood actress, may have drawn your attention to the bottled variety of kombucha (£3.09 in Superquinn), but did you know a growing number of Irish people are brewing the tea, using a fungal culture that enthusiasts pass on freely?

As alternative health therapies have become more popular, so has having a regular health drink to keep your system in balance. "It's a great antacid, and since I've been taking it I no longer have split nails," says Agnes Phelan, who has been drinking a glass of kombucha every morning for the past four years. "We drink a wine glass of it every morning. It's a great drink to cut the palate with," says James Murray, who with his wife, Erica, owns the Hopsack Health Store in Dublin.

Advocates of kombucha claim it relieves arthritis, insomnia and headaches, helps digestive problems, thickens hair, strengthens hair and nails, clears acne, psoriasis and other skin conditions, eliminates menopausal hot flushes and helps muscular aches and pains in the shoulder and neck.

The tea has also been found to be a hangover cure, and because it aids the burning of fat, it can help some people to lose weight. It is not recommended for pregnant or breastfeeding women. And, as with many preventative health drinks and tinctures, those who drink it daily are advised to take a week off every two to three months or a month off every six months.

The culture originated in the East. Some say it was introduced to Japan by Kombu, a Korean doctor, in 414. It was used sporadically for centuries in Asia and found its way to Russia in the 1800s, where it became widely established as a folk medicine.

Kombucha was brought to the West by immigrants from Asian and Eastern European countries. Although sometimes referred to as a mushroom, it is a fungus made up of bacteria and yeasts, nourished by sugar and tea.

The tea is made by placing the kombucha culture in a solution of black or green tea and sugar. This is left to ferment for six-15 days, then filtered for drinking. During the fermenting process, new cultures are formed that can be taken off to start another brew.

Kombucha tea tastes like a lightly sparkling apple cider with a vinegar tang. The sweetness depends on how long it is left to ferment. "It's quite different to the kombucha you buy in the shops," says Murray.

In Britain, Alick Bartholomew, a psychologist, and his wife, Mari, a shiatsu practitioner, were first given a kombucha culture by a cousin in Los Angeles; they brought it back to their Somerset home in 1994 and started a national kombucha network.

The Kombucha Tea Network has about 20 co-ordinators around Britain, each with a band of trusted brewers making kombucha cultures to pass on to anyone who wants one. In the US, there are an estimated three million kombucha tea brewers.

In Ireland, the tea cultures are passed between friends and acquaintances. There is no formal network yet, but some health-store owners, such as the Murrays, pass on the cultures free of charge.

Kombucha cultures are available from the Kombucha Tea Network, P.O. Box 1887, Bath, BA2 8YA. Tel: 00 44 1225 833150. See also www.kombucha.org.uk