There is no magic pill available, either conventional or alternative, to cure every ill. And choosing herbal supplements based on scientific evidence rather than manufacturer's claims can be overwhelming when faced with a plethora of pills staring out at you from store shelves.

"A natural medicine may be popular, even a bestseller, but this doesn't necessarily mean it's the most effective," says Steven Chong, editor of The Journal of Complimentary Medicine.

Steven - along with Dr Luis Vitetta, deputy head and director of research at Swinburne University points out a few of the most popular natural remedies under the spotlight.

Ginkgo Biloba: Looking for a magic pill to whip your grey matter into shape? Emerging evidence suggests ginkgo biloba extract may increase blood flow to the brain, especially in elderly people with poor circulation.

St John's Wort: Also known as Hypericum perforatum, this is a herb used to treat anxiety and mild to moderate forms of depression, according to Chong. On the downside it can interact with some prescription medicines including antidepressants.

Tea: Whether black, green or oolong red, tea has the potential to reduce the risks of cancer, heart disease and osteoporosis. It may also have a role in weight loss and dental health.

Vitamins: Some doctors still say vitamins are "expensive urine" if you have a healthy diet. But many suggest vitamins are useful - because in the fast-food environment, people simply don't consume an optimal amount of all the vitamins by diet alone.

Olive Leaf Extract: Antioxidant-rish olive leaf extract is used to treat symptoms of reduced energy, colds and flu, throat and upper respiratory conditions, coughs and sinusitis.

Selenium: A trace mineral in soil that we get through plants - usually wheat. Even conservative studies find that high levels are associated with protection against various cancers, asthma, depression, viral infections and cardiovascular disease. It also helps thyroid function.

Echinacea: This purple-petalled daisy, mainly used against colds and flu, is one of the bestselling herbal medicines in Australia, but conflicting evidence about its effectiveness abounds

Fish Oil: Known to benefit circulation and help prevent diabetes, strokes and cardiovascular disease. It also benefits cancer patients having chemotherapy.

Probiotics: Contain live bacteria and are found in yogurt or fermented milk products, or are available in capsule form. They help promote good digestion and generally boost immune function.

Glucosamine: A popular proven treatment for arthritis that can help preserve cartilage. It may also help reduce joint swelling.

Nicole Silverman