Fiber and Cardiovascular Risks

by | Nov 19, 2013 | 2013, Cardiovascular Health, Fiber

Written by Jessica Patella, ND. Average Americans do not get the recommended fiber per day. In research with 10,473 participants, those with the lowest fiber intakes had a 36.4% greater incidence of obesity and 34.7% greater incidence of metabolic syndrome- risk factors of cardiovascular problems.  

Fiber is known to decrease cardiovascular risk factors, including metabolic syndrome and inflammation (2-4).  But how are we doing as a country in consuming the required amount of fiber?  Recent research indicates we are far below adequate intakes of fiber and these lower intakes are associated with a greater prevalence of cardiovascular disease risk factors (1).

The recent research included data from the National Health and Nutrition Examination Survey (NHANES), which observed trends among US adults from 1999-2010 (1).  This survey represented a large sample of the US population over a 12-year period and included 10,473 participants (1).

Dietary fiber intake was assessed using 24-hour dietary recalls, during which participants told a trained interviewer what they had consumed in the previous 24 hours.  Based on this information, the average dietary fiber consumption among all the participants was 16.2 grams per day (1).  This is lower than the Institute of Medicine’s recommendations:

  • 38 grams of fiber per day for males aged 19-50
  • 25 grams of fiber per day for males over 50
  • 25 grams of fiber per day for females aged 19-50
  • 21 grams per day for females over 50 (1, 5)

The lowest levels of fiber intake were observed in young black males aged 20-50, with an average fiber intake of 14.7 grams (38 grams is recommended) (1).  Mexican-American and white women 51 years and older had fiber intakes closest to recommended levels (15.6 grams and 15.0 grams respectively, 21 grams recommended) (1).

The highest prevalence of metabolic syndrome (34.7%), inflammation (43.5%), and obesity (36.4%) was observed in participants who consumed the lowest amount of fiber per day, averaging 0-8.1 grams per day (1).

The prevalence of metabolic syndrome, inflammation and obesity each decreased with increased fiber intake (P<0.05, P<0.001, P<0.001, respectively).  Participants who consumed the highest amounts of fiber (22.5-147.6 grams per day) had a significantly lower risk of having metabolic syndrome (RR 0.78, 95%CI 0.70-0.88), inflammation (RR 0.66, 95%CI 0.61-0.72) and obesity (RR 0.77, 95%CI 0.71-0.84) (1).

In conclusion, these findings indicate that dietary fiber is consistently below the recommended intake and fiber intake levels vary across racial/ethnic populations and based on sex (1). In addition, a correlation was observed between cardiovascular risk factors and lower intakes of daily fiber (1).

Additional research is needed to determine effective ways to increase fiber intake among Americans (1).  It is important to note that data was based on a single 24-hour dietary recall which may lead to misclassifications of fiber intakes (1). The benefits found might also be due to other nutrients which were likely to be high in high fiber diets, as the publication did not mention whether these were factored out.

Source: Grooms, Kya N., et al. “Dietary fiber intake and cardiometabolic risks among US adults, NHANES 1999-2010.” The American journal of medicine 126.12 (2013): 1059-1067.

Copyright © 2013 Elsevier Inc. All rights reserved.

Posted November 19, 2013.

Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health.  She earned her ND from Southwest College of Naturopathic Medicine in Tempe, AZ, and is a member of the North Carolina Association of Naturopathic Physicians. Visit her website at  www.awarenesswellness.com.

References:

  1. Grooms KN, et al.  Dietary Fiber Intake and Cardiometabolic Risk among US Adults, NHANES 1999-2010.  2013 Am J Med.  doi: 10.1016/j.amjmed.2013.07.023.
  2. Park Y, et al. Dietary fiber intake and mortality in the NIH-AARP Diet and Health Study. Arch Intern Med. 2011;171(12):1061-1068.
  3. Pereira MA, et al. Dietary fiber and risk of coronary heart disease: a pooled analysis of cohort studies. Arch Intern Med. 2004;164(4):370-376.
  4. Erkkila AT, Lichtenstein AH. Fiber and cardiovascular disease risk: how strong is the evidence? J Cardiovasc Nurs. 2006;21(1):3-8.
  5. Institute of Medicine, Panel on Macronutrients Staff, Subcommittees on Upper Reference Levels of Nutrients, Interpretation, Uses of Dietary Reference Intakes Staff, Standing Committee on the Scientific Evaluation of Dietary Reference Intakes Staff. Summary tables. In: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington, DC: National Academies Press; 2005:1319-1332.