In an analysis of six studies into fruit and vegetable intake, food including spinach, cabbage, cauliflower and broccoli was found to have a significant positive effect.

Green leafy vegetables are thought to have a protective effect because they are high in antioxidants, such as Vitamin C and they may also act to reduce type-2 diabetes risk due to their high magnesium content.

Study Details

The research reviewed six studies involving over 220,000 participants that focused on the links between fruit and vegetable consumption and type-2 diabetes.

It was concluded that eating 1.15 servings of leafy green vegetables a day resulted in a 14 per cent reduced risk of type-2 diabetes when compared with people who ate less than half a serving per day.

This was the equivalent of eating 122 grams of leafy green vegetables per day.

One of the researchers wrote: "there are several possible mechanisms that could explain the benefit of consuming green leafy vegetables in the diet.

"Our results support the evidence that "foods" rather than isolated components such as antioxidants are beneficial for health.

"Results from several supplement trials have produced disappointing results for prevention of disease, in contrast with epidemiological evidence.

"Results from our meta-analysis support recommendations to promote the consumption of green leafy vegetables in the diet for reducing the risk of type 2 diabetes. The results support the growing body of evidence that lifestyle modification is an important factor in the prevention of type 2 diabetes.

"The potential for tailored advice on increasing intake of green leafy vegetables to reduce the risk of type 2 diabetes should be investigated further."

Research Paper Details:

Carter P, Gray LJ, Troughton J, Khunti K, Davies MJ. Fruit and vegetable intake and incidence of type 2 diabetes mellitus: systematic review and meta-analysis. BMJ 2010 341: c4229.