Scientist Dr. Graham Rena and his team at the Neurosciences Institute of the University of Dundee, say however that the research is still at the laboratory stage.

They are hoping for funding to investigate further and replicate their findings in clinical settings.

Green tea has been regarded for a number of years as having health giving benefits but black tea has never before awarded the same qualities.

The team are conducting research for compounds that have the potential to replace insulin in type 2 diabetes, where the body's cells have become resistant to insulin which is a vital regulator of blood sugar.

The research, carried out with researchers from the Scottish Crop Research Institute, revealed that the black tea compounds theaflavins and thearubigins behaved in the same manner as insulin.

Dr. Reno says they found that these compounds are able to mimic insulin action on proteins known as FOXOs (forkhead transcription factor family O) which are known to regulate links between diet and health in many organisms, including mice, worms and fruit flies.

Rena says the challenge now is to see whether these findings can be translated into something useful for human health.

Dr. Rena says the Dundee study is just the first step, and if they can find substances that restore the regulation of the FOXO proteins in people with type 2 diabetes, then these could be used to help them overcome some of the serious health problems that this diagnosis brings.

Dr. Rena cautions against the urge to suddenly start drinking lots of black tea in the hope that it will cure their diabetes because a lot more research is needed.

He says the research into tea compounds is at a preclinical, experimental stage and people with diabetes should continue to take their medicines as directed by their doctor.

Diabetes is the fastest growing epidemic in the world and according to World Health Organization (WHO) estimates, more than 350 million people worldwide will have the disease by 2030.

The research is published in the current issue of the journal Aging Cell.

Among the rodents given a lower dose of the extract along with BBN, 73.9 percent developed bladder cancer.

Tests showed that levels of isothiocyanates in the urine of rodents given the broccoli sprout extract were hundreds or even thousands of times higher than in their blood, suggesting that the tissue lining the bladder known as the epithelium is very highly exposed to the compounds.

Dr. Munday says as the greatest effect was seen in the bladder, the suggestion is that such vegetables protect against bladder cancer.

Dr. Yuesheng Zhang of Roswell Park Cancer Institute in Buffalo, New York and colleagues say the findings support research in humans that shows eating more broccoli and other cruciferous vegetables is associated with a lower risk of the disease.

Dr. Zhang says although this is an animal study, it provides potent evidence that eating vegetables is beneficial in bladder cancer prevention.