The humble mushroom could hold the key to finding a cure for cancer, according to new research.

It contains chemicals that destroy tumours - offering hope of developing drugs without side effects.

Current chemotherapy medications cause a range of problems from loss of hair to nausea.

The mysterious fungus has been used in Chinese medicine for thousands of years.

And the ancient Egyptians believed eating mushrooms brought long life.

There are thousands of species growing in the wild. Now a reviewed of data on just four has found they have the potential to treat a variety of tumours.

These include blood, bowel, stomach, liver, bone and soft tissue cancers - along with more.

Professor Vladimir Katanaev, of the Far Eastern Federal University, Vladivostok, Russia, said there will be many more types of mushrooms that are just as effective.

He said: "In ancient China mushrooms were considered as the most effective treatment for the various types of tumours.

"Contemporary fungotherapy - treatment by means of mushrooms - represents a promising field for scientific research.

"The natural chemical compounds contained in fungi have a huge therapeutic and particularly anti-cancer potential that has not been yet fully studied."

The study published in Oncotarget says they may provide alternative treatments to chemotherapy or be used in combination with such medications.

Prof Katanaev's team analysed mushrooms widely used in Asian and Far Eastern medicine.

The species Fomitopsis pinicola, Hericium erinaceus, Inonotus obliquus and Trametes versicolor were shown to target malignant tumours while leaving healthy cells alone.

Mushrooms are rich in antioxidants called polyphenols, carbohydrates, steroids, fats and proteins that kill cancerous cells and boost chemotherapy.

Some of the four species are already used in the manufacture of cancer drug in China and elsewhere.

Prof Katanaev said, undoubtedly, there are many other species of fungi that contain chemical compounds to defeat cancer cells.

But his co-author Dr Alexander Kagansky, a colleague at the same university, said despite the interest in the medicinal use of mushrooms over the last 60 years, about nine in ten species have never been analysed for antibiotic and anti-tumour activities.

The first generation of natural medical compounds from mushrooms' extracts wasn't specific and has been used without consideration of the properties of different tumours.

There were lots of heavy side-effects at times leading to the death of the patient due to the overdose.

Modern approaches to anti-cancer therapy are based on the targeted treatment with minimal or no consequences to the healthy cells and tissues.

For this purpose, not only the general therapeutic properties of fungal chemical compounds are investigated but also the ways they differ in their action on different tumours.

The scientists hope the high potential of mushrooms they have identified will encourage further research.

They are now carrying out experiments to reveal the anti-cancer activities of the mushroom extracts.

They hope it will lead to the creation of a new generation of highly specific low-toxic drugs, which could be specifically targeted for different cancers.

Last year a US study suggested eating mushrooms could help ward off diseases including cancer and dementia.

It found they reduce 'free radicals' in the body which contribute to disease thanks to high levels of two antioxidants.

In countries where mushroom consumption is high, such as France and Italy, there are fewer cases of Alzheimer’s disease.

Just a small portion five days a week is enough to make a difference.

Wild porcini mushrooms contain large amounts of the antioxidants ergothioneine and glutathione.

Even the common button mushroom contains more of these powerful compounds than most other foods.