Antioxidant vitamins, the once promising antidote to heart disease and cancer have become the red-headed stepchildren in the world of nutritional research. The latest bad news is that not only is it not effective for diabetics, it may actually worsen it.

The study - published in a recent issue of Cell Metabolism suggests that chronically low levels of ROS (Reactive Oxygen Species - or free radicals) may actually protect us from diabetes by improving our ability to respond to insulin signals.

In a way, we think there is a delicate balance and that too much of a good thing - surprise, surprise - might be bad.

Says researcher Tony Tiganis of Monash University in Australia.

And isn't that just a microcosm of how most things work in nutrition!

The antioxidant theory had such promise and seemed wonderfully simple - free radical damage (ROS) causes chronic disease, antioxidant vitamins squelch free radicals - therefore take antioxidants to reduce your risk of chronic disease. 

Well the excitement soon died off when research went from in vitro to in vivo. Long-term trials came up empty and in some cases the antioxidant treatment arm even increased risk of certain diseases in certain populations.

A recent study for example indicates that antioxidants may negate the longer-term benefits of exercise training by lowering the activity of certain genes involved in ROS defence.

Stick with real food

It's not to say there isn't ever a use for supplemental antioxidants. Somewhere along the way, however we've become hyperfocused on trying to tease out components of food when in fact the whole food is much better than the sum of its parts.

As far as this study is concerned, it was on mice - so take that for what it's worth. Further, of all the things are that are bad for diabetics, antioxidants rank distantly behind excess calories - particularly sugar and refined carbohydrates and sedentary behaviour - start there!