Dietary Fibre

It is well known that fibre, in appropriate quantities, is an important part of a healthy diet. There are different types of fibre, each benefiting the body in different ways. Soluble fibre mixes with water in the intestine to form a gel-like substance, which acts as a trap to collect certain body wastes and then move them out of the body. Insoluble fibre absorbs and holds water, producing uniform stool and helping to push gut contents through the digestive system quickly. Insoluble fibre in appropriate amounts and with additional fluid intake can promote bowel regularity and improve constipation.

The Consortium for Spinal Cord Medicine (1998) recommends an initial diet with no less than 15 grams of fibre daily, and the Multidisciplinary Association of Spinal Cord Injury Professionals (MASCIP) (2009) group recommends an average intake of 18 grams, however, they acknowledge that adjustments should be made if problems arise with stool consistency. It is currently not recommended to uniformly place individuals with SCI on high fibre diets due to individual differences and tolerances (Consortium for Spinal Cord Medicine 1998).

Discussion

While many individuals with SCI report that adjusting their diet improves bowel function (Coggrave et al. 2006b), there is scant evidence to support this. Cameron et al. (1996) looked at increasing dietary fibre and found that this does not have the same effect in individuals with SCI as has been previously demonstrated in individuals without neurogenic bowel dysfunction. The effect may actually be the opposite of the desired result. Therefore, adding more fibre alone does not improve bowel function; for individuals with low fibre intake and constipation, fibre in the diet may be increased gradually and the effect on bowel function carefully observed. More evidence is required to assess the effectiveness of adding fibre to the diet of individuals with SCI.

Conclusion

There is level 4 evidence (from one case series; N=11: Cameron et al. 1996) that indicates high fibre diets may lengthen colonic transit time in individuals with SCI.

Author Year; Country

Score

Research Design

Total Sample Size

Methods Outcome
Cameron et al., 1996; Australia

Case Series

N=11

Population: Age: range 19-53yrs; Level of injury: C4-T12; 1 subject with incomplete injury and 10 with complete injuries; 7 participants with tetraplegia and 4 with paraplegia. All participants were in their first rehabilitation program 1-4 months after injury.

Treatment: In phase 1 (week 1), participants ate a normal hospital diet and maintained their bowel routine. In phase 2 (week 2-4), fibre intake was increased with the addition of 40g Kellogg’s All Bran.

Outcome Measures: stool weight, total and segmental transit time, bowel evacuation time and dietary intake.

1. Following the addition of bran, dietary fibre intake significantly increased from 25g/d to 31g/d.

2. Mean colonic transit time significantly lengthened from 28.2 hours to 42.2 hours