December 26, 2005

More Evidence Seen for Fiber Cutting Heart Risks

By Amy Norton

NEW YORK -- A diet that includes diverse sources of fiber may help prevent several major risk factors for heart disease, a study of French adults suggests.

The study of nearly 6,000 men and women found that the higher the participants' fiber intake, the lower their risk of being overweight or having elevated blood pressure or cholesterol.

The researchers also found that fiber from different sources had somewhat different effects. Fiber from whole grains, for example, was linked to lower body mass index (BMI), blood pressure and levels of a blood protein called homocysteine, which is connected to heart disease risk.

Fruit fiber was associated with lower blood pressure and less abdominal fat, while fiber from vegetables appeared to lower the risk of high blood pressure and high homocysteine concentrations.

And fiber from nuts, dried fruit and seeds was linked to a lower BMI, a lesser risk of abdominal obesity and lower blood sugar levels.

These findings all point to the importance of getting fiber from a variety of sources, according to Denis Lairon, a researcher at the French national health institute INSERM and the study's lead author.

The results also suggest that adults would do well to get more than the recommended fiber intake of roughly 25 grams per day, Lairon and his colleagues say. In their study, each 5-gram increase above that was linked to a greater decrease in the risks of being overweight or having high blood pressure or high cholesterol.

People can generally have fiber intakes of up to 70 grams a day without having digestive symptoms such as bloating and cramping, Lairon told Reuters Health. He added, though, that a sudden jump in roughage intake might cause some problems.

The study findings, published in the American Journal of Clinical Nutrition, are based on information on diet and lifestyle habits gathered from 5,961 adults ages 35 to 60. The men and women were separated into five group based on fiber intake.

Lairon's team found that those with highest total intake had a 30 percent lower risk of being overweight -- with factors like age, calorie intake, exercise and smoking taken into account.

They had similarly lower risks of high blood pressure and elevated cholesterol compared with their peers who ate the least fiber.

The findings add to evidence that fiber does a heart good, but also suggest, according to Lairon and his colleagues, that 25 grams per day is the "minimum" needed to reap significant benefits.

In the U.S., it's been estimated that the average adult eats only about 15 grams of fiber a day.

SOURCE: American Journal of Clinical Nutrition, December 2005.