HTN: Soluble Fiber 2008
Click here to see the explanation of recommendation ratings (Strong, Fair, Weak, Consensus, Insufficient Evidence) and labels (Imperative or Conditional). To see more detail on the evidence from which the following recommendations were drawn, use the hyperlinks in the Supporting Evidence Section below.
Advise that the consumption of soluble fiber may or may not be beneficial for the reduction of blood pressure, since the effect of increased soluble fiber intake on blood pressure is unclear.
Risks/Harms of Implementing This Recommendation
It is concluded that as part of an overall healthy diet, a high intake of dietary fiber will not produce deleterious effects in healthy individuals. While occasional adverse gastrointestinal symptoms are observed when consuming some isolated or synthetic fibers, serious chronic adverse effects have not been observed.
Conditions of Application
No conditions specified.
Potential Costs Associated with Application
Of six randomized controlled trials, four report no significant differences in systolic or diastolic blood pressure at consumption levels of 5.5 to 8.4g of different types of soluble fiber for one month to six months (Davy et al, 2002; Jenkins et al, 2002; He et al, 2004; Marett and Slavin, 2004).
However, in two randomized controlled trials (one of which involved weight reduction), consumption of oats (6 - 7 g soluble fiber) for six to 12 weeks resulted in significant reductions of systolic and diastolic blood pressure (Saltzman et al, 2001; Pins et al, 2002).
A meta-analysis (Streppel et al, 2005) of studies investigated increased fiber consumption, including soluble fiber, reports modest reductions in systolic blood pressure of 1.32 to 1.74mm Hg and in diastolic blood pressure of 0.82 to 2.22mm Hg (dose of soluble fiber intake not reported).
Recommendation Strength Rationale
- Conclusion Statement is Grade III
- Risks/Harms of Implementing This Recommendation
The recommendations were created from the evidence analysis on the following questions. To see detail of the evidence analysis, click the blue hyperlinks below (recommendations rated consensus will not have supporting evidence linked).
What is the relationship between soluble fiber intake and blood pressure in healthy and hypertensive adults?
Davy BM, Melby CL, Beske SD, Ho RC, Davrath LR, Davy KP. Oat consumption does not affect resting casual and ambulatory 24-h arterial blood pressure in men with high-normal blood pressure to stage 1 hypertension. J Nutr. 2002; 132: 394-398.
He J, Streiffer RH, Muntner P, Krousel-Wood MA, Whelton PK. Effect of dietary fiber intake on blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens. 2004; 22: 73-80.
Jenkins DJA, Kendall CWC, Vuksan V, Vidgen E, Parker T, Faulkner D, Mehling CC, Garsetti M, Testolin G, Cunnane SC, Ryan MA, Corey PN. Soluble fiber intake at a dose approved by the US Food and Drug Administration for a claim of health benefits: serum lipid risk factors for cardiovascular disease assessed in a randomized controlled crossover trial. Am J Clin Nutr. 2002; 75: 834-839.
Marett R, Slavin JL. No long-term benefits of supplementation with arabinogalactan on serum lipids and glucose. J Am Diet Assoc. 2004; 104: 636-639.
Pins JJ, Geleva D, Keenan JM, Frazel C, O'Connor PJ, Cherney LM. Do whole-grain oat cereals reduce the need for antihypertensive medications and improve blood pressure control? J Fam Practice. 2002; 51 (4): 353-359.
Saltzman E, Das SK, Lichtenstein AH, Dallal GE, Corrales A, Schaefer EJ, Greenberg AS, Roberts SB. An oat-containing hypocaloric diet reduces systolic blood pressure and improves lipid profile beyond effects of weight loss in men and women. J Nutr. 2001; 131: 1,465-1,470.
Streppel MT, Arends LR, van’t Veer P, Grobbee DE, Geleijnse JM. Dietary fiber and blood pressure: A meta-analysis of randomized placebo-controlled trials. Arch Intern Med. 2005;165:150-156.
References not graded in Academy of Nutrition and Dietetics Evidence Analysis Process
The Dietary Reference Intakes (DRI) and Recommended Dietary Allowances (RDA) are issued by the Food and Nutrition Board of the Institute of Medicine, National Academy of Sciences.