Assessment of gastrointestinal tolerance of three novel type 4 resistant starches in a human intervention study

• Author / Creator

  Chen Yang

• Background: Dietary fibre (DF) offers potential health benefits, yet intake in Canada is half of that recommended. A type of DF known as resistant starch (RS) can replace digestible carbohydrates in flour-based foods and is typically well tolerated, offering potential physiological benefits to the consumer. However, before novel RS can be used to enrich the food supply with DF, an assessment of gastrointestinal (GI) tolerance is essential. The objective of this study was to assess the GI tolerance of three novel variants of RS type 4 (RS4) at increasing doses from 10 to 50 g/day in healthy adults.
  Method: In a randomized, double-blind, placebo-controlled, parallel four-arm human trial, 40 participants were assigned to consume either one of three RS4s (derived from either hi-maize, potato, or tapioca starch) or digestible corn starch (placebo). During the four-week dietary intervention, the dose of RS4 was increased weekly from 10 g to 50 g/day. A composite GI tolerability score (sum of individual GI symptoms; score ranged from 0 to 12), bowel movement habits, and perceived satiety were assessed at the end of each study week.
  Results: Overall, the average supplementation compliance was high at 98.9%. Composite GI tolerability score was significantly affected by increasing supplementation dose, with moderate yet significant increases in composite score reported at doses ≥35 g/d in all treatments except Potato RS4. No significant difference was detected between RS4 treatments and placebo. A 50g/d dose of Potato RS4 led to looser stool but not the other supplementation. Supplementation with RS4s or placebo did not significantly affect percived satiety reported upon awaking nor 2- hours after a meal relative to baseline. The effect of dose on perceived satiety was only significant at four hours after a meal enriched with Potato RS4 at the 35 g/d dose.
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  Conclusion: The novel RS4s tested are well tolerated when compared to other RS types and DFs, and no differences were detected compared to digestible corn starch. Therefore they are promising DFs for closing the ‘fiber gap’, as they can be used up to doses of 50 gram. To optimally use these RS4s to fill the ‘fiber gap’, additional human intervention studies evaluating physiologically relevant health markers of these novel RS4s are necessary where doses of at least 35 g/day are supplemented. Potato RS4s may be able to increase perceived satiety. However, due to the high inter-individual variation at baseline and the low sample size, further investigation on RS4 effects on satiety would be favorable to reinforce this finding. The findings obtained in this study provide important pilot information for the development of future nutritional studies that aim at closing the “fibre gap”.

• Subjects / Keywords

  • Resistant Starch Type 4; dietary fibre; gastrointestinal symptoms; bowel habits; perceived satiety

• Graduation date

  Fall 2019

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-h9sv-fm73

• License

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