Why you need more fibre

Most of us haven't a clue how many grams of fibre we get from our diets in a typical day. Yet for many people in the UK, this number should be doubled.

The British Nutrition Foundation reports that most of us don't even come close to the recommended intake of at least 18g of fibre a day. On average, people in the UK get only about 12g of fibre a day.

That's not surprising when you consider that we get fibre from ?roughage? in fruit, vegetables, wholegrains, nuts/seeds and pulses. The typical person isn't exactly loading his or her plate with these foods (you'd be hard-pressed to find a fruit, vegetable, wholegrain or pulse in your average fast-food value meal).

Why is fibre so good for us?

Eating a higher-fibre diet has been shown to lower blood cholesterol levels, improve and prevent constipation, and improve digestion. According to Dr Barbara Rolls, author of The Volumetrics Eating Plan, fibre can help us eat less - and lose weight.

"Simply doubling the amount of fibre you eat from the average of 15g per day to around 30g helps reduce calorie intake," Rolls explains. "Fibre has been shown to increase satiety, not only by lowering the energy density of foods (that is, how many calories they have per serving) but also by slowing the rate that foods pass through the digestive systems."

When you increase dietary fibre, do it gradually to avoid gastric distress, and drink plenty of fluids to avoid constipation.

Dr Joanne Slavin, an obesity researcher at the University of Minnesota in the US, says dietary fibre not only makes us feel fuller, but reduces digestibility. Some studies have shown that large amounts of fibre in the diet can help to regulate blood glucose and insulin. These may be reasons why people who eat higher-fibre diets tend to weigh less and are less prone to gain weight as they age.

The research findings on fibre's benefits keep pouring in. Some studies have shown that:

• Eating a higher-fibre diet, as part of an overall healthy lifestyle, may play a role in a healthy BMI (body mass index). One study found that women who ate more wholegrains and total fibre consistently gained less weight over 12 years than those who ate less fibre and wholegrains. Another study found that women with low-fibre, high-fat diets were more likely to be overweight than those following high-fibre, low-fat diets. Dr Megan McCrory, one of the study's researchers, notes that women should place greater emphasis on eating more fibre.
• A high-fibre diet may reduce your risk of colon cancer. If populations with a low average fibre intake suddenly doubled their fibre by making wiser food choices, they could lower their risk of colon cancer by 40%, according to a study involving data collected from 10 European countries. A National Cancer Institute study also linked high fibre intakes to a lower risk of colorectal cancer. This was especially true for fibre from grains, cereals and fruits.
• Fibre may reduce the risk of type 2 diabetes. Those who ate a diet high in refined carbohydrates and low in cereal fibre were more likely to increase their risk of type 2 diabetes, according to a study. A Finnish study showed that as wholegrain and cereal fibre intake increased, the risk of type 2 diabetes seemed to decrease. However, it may not just be all about the fibre in this case; high-fibre foods are also rich in important micronutrients. That's why it's better to concentrate on including whole plant foods in your diet than to take a fibre supplement.

Fibre intake has also been linked to the metabolic syndrome, a cluster of risk factors that increase the chances of developing heart disease and diabetes:

• Higher intakes of fibre (from cereal and wholegrain products) were linked with a slower build up of cholesterol-filled plaque of the arteries in postmenopausal women with coronary artery disease. In another study, in men and women between 40 and 60 years old and free of heart disease, viscous fibre (especially pectin, the type of soluble fibre found in apples) appeared to protect against the progression of atherosclerosis in neck arteries.
• High intakes of oat fibre appeared to have a protective effect on the heart, by lowering LDL "bad" cholesterol without decreasing HDL "good" cholesterol.