Analysis of eight studies on diet and stroke published between 1990 and 2012 has found that risk of first-time stroke dropped with every 7g increase in total daily fibre. That amount of fibre is contained in a bowl of wholewheat pasta plus two servings of fruit or vegetables.

Insufficient data is available to say whether soluble or insoluble fibre is better. The studies came from the United States, northern Europe, Australia, and Japan.

http://www.guardian.co.uk/science/2013/mar/28/high-fibre-diet-stroke-risk

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Stroke.