If I offered you a superaliment that would make you live longer, would you be interested?
Of course, it reduces the chances of debilitating heart attacks and strokes and life-long illnesses such as type 2 diabetes [1
I must say that it is cheap and widely available in the supermarket.
What is it?
Fibers – it's not the sexiest thing in the world, but an important study has investigated how much fiber we really need to eat and we've discovered that there are huge health benefits.
"The evidence is now overwhelming and this is a turning point for people to start doing something about it." One of the researchers, Prof John Cummings, tells BBC News.
It is well known for stopping constipation – but its health benefits are much larger than that.
How many fibers do we need?
Researchers at the University of Otago, New Zealand, and at the University of Dundee say people should eat at least 25g of fiber a day.
But they call it an "adequate" amount to improve health and say that there are benefits to push over 30g (1oz).
Is that all?
Well, a banana alone weighs about 120 g but that is not pure fiber. Eliminate all the rest, including all natural sugars and water, and you only have about 3 g of fiber left.
Most people around the world consume less than 20g of fiber each day.
And in the United Kingdom, less than one in 10 adults eat 30g of fiber a day.
On average, women consume about 17 g, and men 21 g, per day.
What other foods have more fiber in them?
You find it in fruits and vegetables, some breakfast cereals, bread and pasta that use whole grains, legumes like beans, lentils and chickpeas, as well as nuts and
BBC Food: How smart are you?
What is the appearance of 30g?
Elaine Rush, a nutrition professor at the University of Technology of Auckland, put together this example to enter the 25 -30g field:
- half cup of oat flakes – 9g fiber | two Weetabix fibers – 3g | a thick slice of brown bread – 2g fiber | a cup of cooked lentils – 4g fiber | a potato cooked with su – fiber skin 2g | half a cup of chard (or silverbeet in New Zealand) – fiber 1g | a carrot – 3g fiber | an apple with skin on – 4g fiber
But she says: "It is not easy to increase fiber in the diet".
Prof Cummings is on agreement. "It's a big change for people," he says. "It's a real challenge."
Are there any quick and easy suggestions?
The National Health Service of the United Kingdom has a full page of
- cooking potatoes with skin | exchanging white bread, pasta and rice for full versions | choice of breakfast cereals with high quality fibers such as polenta-based oats in which some chickpeas are fed, beans or lentils in a curry or on a salad | dried fruit or fresh fruit for snacks or desserts consuming at least five portions of fruit or vegetables every day
BBC Food: high-fiber breakfasts
What will be the benefit?
Well, after analyzing 185 studies and 58 clinical trials, the results are and have been published in the medical journal Lancet.
Suggests that if 1,000 people were moved from a low-fiber diet (less than 15 g) to a high-fiber diet (25-29 g), then 13 deaths and six cases of heart disease would be avoided.
This is in the course of these studies, which tended to follow people for one or two decades.
Also showed lower levels of type 2 diabetes and intestinal cancer, in addition to lower weight, blood pressure and cholesterol levels.
And the more the fibers ate, the better it was.
What does fiber do in the body?
At one time it was thought that fiber did not do much – that the human body could not digest it and that it was only navigated.
But the fiber makes us feel satiated and influences the way fat is absorbed in the small intestine – and things get really interesting in the large intestine, when the intestinal bacteria come to dine.
The large intestine is home to billions of bacteria – and fiber is their food.
It's like a brewery down there, certainly one from which you do not want a pint, where bacteria are fermenting fibers to produce a whole load of chemicals.
This includes short-chain fatty acids, which are absorbed and have effects on the whole body.
"We have created this organ to digest the fiber, which many people simply do not use much", says prof. Cummings.
Why is this relevant now?
The fact that fiber, whole grains and fruits and vegetables are healthy should not be surprising.
But there's the concern that people turn their backs on fiber, with the popularity of low carbohydrate diets.
Prof Nita Forouhi, of the University of Cambridge, says: "We must take a serious note of this study.
" His results imply that, although increasingly popular in the community at large, any diet that Low carb diets recommending diet should consider the opportunity cost of losing fiber from whole grains.
"This research confirms that fiber intake and whole grains are clearly important for long-term health."
The study was done to help the World Health Organization to develop official guidelines on how many people in the fiber should eat to improve health and are expected for next year.
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Analysis from BBC Reality Check
One of the suggested ways to increase the amount of fiber in your diet is to switch from white to brown or wholemeal bread.
is what is happening to the sales of those products, based on a series of government surveys on household spending since 1974.
From the mid-seventies to the mid-eighties, white bread fell while brown and the whole flour went up.
Since then, sales of white bread have continued to decline, but sales of brown and brown bread have declined for most of that period, albeit at a slower pace.
So it seems that while the overall demand for bread has been falling, a higher percentage of bread sold has been higher in fiber.
Wholemeal pasta made less impact on sales than higher fiber bread, with a survey by the British Journal of Nutrition that found that pasta represented less than 1% of the occasions when people were consuming whole grains.