More fibre, not less sat fat, may be key for metabolic syndrome: Study

A diet high in fibre – but not necessarily one low in saturated fat or cholesterol – is associated with lower risks of heart disease and type-2 diabetes in teenagers, according to new findings.

The study – published in the Journal of the American Dietetic Association – suggests the number of teens with metabolic syndrome (MetS) could be reduced if the much of the focus was shifted from towards eating healthier rather than cutting out ‘unhealthy’ foods.

The researchers from Michigan State University, USA, argued that results from their study suggest that it is more important to encourage the intake of nutrient-dense, fibre-rich, plant based foods and meals than to restrict foods that are high calories or saturated fat.

"What we found is that as fibre intake increases, the risk for metabolic syndrome decreases," said Dr Joseph Carlson of Michigan State (MSU).

"High-fibre, nutrient-dense foods are packed with heart healthy vitamins, minerals and chemicals that can positively affect many cardiovascular risk factors ... It may be better to focus on including these foods than to focus, as is commonly done, on excluding foods high in saturated fat," he suggested.

However, Carlson added that his suggestion does not mean that teens should have carte blanche in eating foods high in saturated fat and cholesterol.

"It is well established that saturated fat can raise bad cholesterol," he said. "What this data suggest is the importance of including foods high in dietary fibre."

Study details

Carlson and his team used data collected as part of the National Health and Nutrition Examination Survey (1999-2002) to analyse the diets of more than 2,100 teenage boys and girls aged between 12 and 19.

The researchers then analysed how dietary intake of fibre and saturated fats impacted the incidence of metabolic syndrome – finding a three-fold increase in the incidence of MetS between those receiving the least fibre and the group receiving the most.

When it came to cholesterol and saturated fat intake, however, the MSU research team did not find a significant relationship between intake and metabolic syndrome incidence.

“These findings suggest that to reduce the risks for MetS in adolescents, it is more important to emphasize a paradigm that promotes the inclusion of fiber-rich, nutrient-dense, plant-based foods vs what foods to restrict or exclude as is commonly done when the focus is on total fat, cholesterol, or saturated fat intake,” they concluded.

Carlson added that a strategy “of emphasising fibre-rich foods may improve adherence to dietary recommendations.”

"One of the takeaways is that our study reinforced the current dietary recommendations for dietary fibre intake by including a variety of plant-based foods," he explained.

The next step, he said, is to work out the best methods to boost fibre intakes to levels that will improve or sustain a desirable cardiovascular risk factor status

"The trick is getting people in the groove finding the foods that they both enjoy and are convenient," said Carlson.

Source: Journal of the American Dietetic Association

Volume 111, Issue, 11, Pages 1688-1695, doi: 10.1016/j.jada.2011.08.008

“Dietary Fiber and Nutrient Density Are Inversely Associated with the Metabolic Syndrome in US Adolescents”

Authors: J.J. Carlson, J.C. Eisenmann, G.J. Norman, K.A. Ortiz, P.C. Young