Why stevia may not be the quick fix to our sugar crisis

Sugar is clearly public enemy number one right now, with a swathe of media attention around George Osborne’s sugar levy.

Not known to many, I think, is the fact that the first serious warning about too much sugar in our diet appeared over 40 years ago. A very good British scientist by the name of John Yudkin published a book called Pure, White and Deadly.

His work was slammed by the sugar industry, food industry and quite a lot of nutritionists into the bargain. Forty years on, Yudkin’s work has been described, quite rightly, as “prophetic”.

The scramble is now well and truly on to find alternatives to sugar. After all, sugar causes a multitude of health problems, such as heart disease and diabetes. It is the diabetes issue that really got me thinking. Sugar acts as an endocrine disrupting agent - ie it has a huge negative effect on the pancreas that produces the insulin we need to regulate our blood glucose levels.

One of the natural alternatives to sugar now being widely promoted and, indeed, incorporated into many foods is steviol glycosides, extracted from the leaves of a South American stevia plant.

When I recently discussed this within the Institute for Global Food Security at Queen’s University, I was taken aback that my colleague, Dr Lisa Connolly, working alongside world-leading researchers, has discovered that steviol, a metabolite of steviol glycosides, may well be a potent endocrine disruption agent itself. Their research has found some disturbing evidence that this natural compound may affect the hormonal pathways associated with human reproduction and may have links with a number of other serious disorders.

I have to quickly state this is contrary to some other research findings and also that bodies such as the World Health Organization have found no health risks with the consumption of this compound. However the new study, just published in the international scientific journal Molecular and Cellular Endocrinology, should act as a warning to us all that the huge problem of reducing our sugar intake may not be solved by simply switching to consuming large amounts of stevia.

Professor Chris Elliott is director of the Institute of Food Safety at Queen’s University, Belfast