The Benefits of Fiber: How it Helps With Digestion
High fiber diets have numerous reported health benefits. It is a widely recommended healthy diet. Here are some health benefits high fiber diets have been associated with1,2,3,4,5,6,7,8:
- reduced risk of type 2 diabetes
- reduced risk of certain forms of cancer
- reduced risk of obesity/enhanced weight control
- reduced risk of stroke
- reduced risk of cardiovascular, coronary heart, and respiratory disease
- lower serum cholesterol concentrations
- reduced blood pressure
- improved gastrointestinal function
Scientific research shows high-fiber foods enable butyrate-producing bacteria to thrive1. Butyrate is a short chain fatty acid which is most commonly produced via fermenting fiber by bacteria in the colon9. Cells in the colon use butyrate as their primary source of energy10.
Butyrates have been shown to:
- Help neurons grow and survive11,12,13,14,15,16,17,18,19,20,21,22,23,24. Neurons transmit information throughout the body and tell muscles, joints, and organs what to do
- Resist oxidative stress, which will help the body detoxify harmful chemicals21,23,25 ,26
- Increase expression of learning-associated genes27,28, which can help improve memory function
A specific type of fiber is inulin. Inulin is a prebiotic fiber that helps nourish beneficial bacteria in your gut. Inulin helps reduce blood glucose and oxidative stress29,30. Inulin helps reduce body weight and improves glycemic control and antioxidant levels in type 2 diabetes patients31. Inulin can also increase colonic short-chain fatty acid production, which may reduce type 2 diabetes risk32.
These are some of the scientifically proven benefits of fiber. Two large prospective cohort studies (with a combined 1.5 million participants) found higher fiber diets were linked to a lower risk of death8,33,34.
Fiber can be found in beans, whole grains, brown rice, nuts, berries, and many other sources. To easily get 2500 mg of fiber, including inulin, and 25 servings of fruit and vegetables daily
References:
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16. R.B. Varela, S.S. Valvassori, J. Lopes-Borges, E. Mariot, G.C. Dal-Pont, R.T. Amboni, et al. Sodium butyrate and mood stabilizers block ouabain-induced hyperlocomotion and increase BDNF, NGF and GDNF levels in brain of Wistar rats. J. Psychiatry Res., 61 (2015), pp. 114–121.
17. S.S. Valvassori, R.B. Varela, C.O. Arent, G.C. Dal-Pont, T.S. Bobsin, J. Budni, et al. Sodium butyrate functions as an antidepressant and improves cognition with enhanced neurotrophic expression in models of maternal deprivation and chronic mild stress. Curr. Neurovasc. Res., 11 (2014), pp. 359–366.
18.K.A. Intlekofer, N.C. Berchtold, M. Malvaez, A.J. Carlos, S.C. McQuown, M.J. Cunningham, et al. Exercise and sodium butyrate transform a subthreshold learning event into long-term memory via a brain-derived neurotrophic factor-dependent mechanism. Neuropsychopharmacology, 38 (2013), pp. 2027–2034.
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20.G. Gardian, S.E. Browne, D.-K. Choi, P. Klivenyi, J. Gregorio, J.K. Kubilus, et al. Neuroprotective effects of phenylbutyrate in the N171-82Q transgenic mouse model of Huntington’s disease. J. Biol. Chem., 280 (2005), pp. 556–563.
21. B. Langley, M.A. D’Annibale, K. Suh, I. Ayoub, A. Tolhurst, B. Bastan, et al. Pulse inhibition of histone deacetylases induces complete resistance to oxidative death in cortical neurons without toxicity and reveals a role for cytoplasmic p21(waf1/cip1) in cell cycle-independent neuroprotection. J. Neurosci., 28 (2008), pp. 163–176.
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32.Wolever, Thomas M.S. (2010). The fermentable fibre inulin increases postprandial serum short-chain fatty acids and reduces free-fatty acids and ghrelin in healthy subjects. Applied Physiology, 35(1), 9-16.
33.Lehman, S. (2015, January 12). Higher-Fiber Diet Linked to Lower Risk of Death.
34.Yang, Y., Zhao, L., Wu, Q., Ma, X., & Xiang, Y. (2015). Association Between Dietary Fiber and Lower Risk of All-Cause Mortality: A Meta-Analysis of Cohort Studies. American Journal Of Epidemiology, 181(2), 83-91.
Journal Of Epidemiology, 181(2), 83-91.