A new study published in the December issue of The American Journal of Medicine
shows a significant association between low dietary fiber intake and
cardiometabolic risks including metabolic syndrome, cardiovascular
inflammation, and obesity. Surveillance data from 23,168 subjects in the
National Health and Nutrition Examination Survey (NHANES) 1999-2010 was
used to examine the role dietary fiber plays in heart health.
In the current study investigators have taken a closer look at
possible sex, age, racial/ethnic, and socioeconomic disparities in
dietary fiber consumption, as well as examined the association between
dietary fiber intake and various cardiometabolic risk factors.
Dietary fiber, which previous studies have shown may assist in
lowering blood pressure, cholesterol levels, and inflammation, is
thought to play an important role in reducing cardiovascular risk.
Despite this knowledge, investigators found that dietary fiber intake
was consistently below recommended intake levels for NHANES
participants.
The Institute of Medicine defines recommended intake levels
according to age and sex: 38g per day for men aged 19-50 years, 30g per
day for men 50 and over, 25g for women aged 19-50 years, and 21g per day
for women over 50. Using data from NHANES 1999-2010, the study reveals
that the mean dietary fiber intake was only 16.2g per day across all
demographics during that time period.
"Our findings indicate that, among a nationally representative
sample of nonpregnant US adults in NHANES 1999-2010, the consumption of
dietary fiber was consistently below the recommended total adequate
intake levels across survey years," says senior investigator Cheryl R.
Clark, MD, ScD, Center for Community Health and Health Equity, Brigham
and Women's Hospital and Harvard Medical School, Boston. "Our study also
confirms persistent differences in dietary fiber intake among
socioeconomic status and racial/ethnic subpopulations over time."
The research team found variations according to race and ethnicity,
with Mexican-Americans consuming higher amounts of dietary fiber and
non-Hispanic blacks consuming lower amounts of dietary fiber compared
with non-Hispanic whites.
The study highlights the importance of increasing dietary fiber
intake for US adults by showing a correlation between low dietary fiber
and an increased risk for cardiovascular risk. Participants with the
highest prevalence of metabolic syndrome, inflammation, and obesity were
in the lowest quintile of dietary fiber intake.
"Overall, the prevalence of the metabolic syndrome, inflammation,
and obesity each decreased with increasing quintiles of dietary fiber
intake," comments Clark. "Compared with participants in the lowest
quintile of dietary fiber intake, participants in the highest quintile
of dietary fiber intake had a statistically significant lower risk of
having the metabolic syndrome, inflammation, and obesity."
This new data analysis emphasizes the importance of getting adults
across diverse ethnicities to increase their dietary fiber intake in
order to try and mitigate the risk for cardiovascular damage.
"Low dietary fiber intake from 1999-2010 in the US and associations
between higher dietary fiber and a lower prevalence of cardiometabolic
risks suggest the need to develop new strategies and policies to
increase dietary fiber intake," adds Clark. "Additional research is
needed to determine effective clinical and population-based strategies
for improving fiber intake trends in diverse groups."
