NCT00981981

Effect of the Molecular Weight of Oat β-glucan on Its Ability to Lower Serum Cholesterol

Effect of Varying Dose and Molecular Weight on the Serum LDL-cholesterol-lowering Properties of Oat β-glucan

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 367 (actual)
• Sponsor: Glycemic Index Laboratories, Inc · Industry
• Sex: All
• Age: 35 Years – 70 Years
• Healthy volunteers: Accepted

Summary

The purposes of this study were: 1. To determine if a breakfast cereal containing 3g of high molecular weight oat beta-glucan fiber would lower low-density lipoprotein (LDL) - cholesterol (the "bad" cholesterol) compared to a control cereal containing wheat fiber. 2. To determine if the LDL-cholesterol-lowering effect of oat beta-glucan fiber was reduced when the molecular weight of the fiber was reduced.

Detailed description

The FDA allows a health claim that oat products may reduce the risk of heart disease, based on meta-analyses showing a cholesterol-lowering effect of oat beta-glucan, if the product delivers at least a 3g daily dose of oat beta-glucan. However, not all studies have demonstrated a lowering of oat products. This may be due to variable bioactivity of the beta-glucan in the oat products. The bioactivity of oat beta-glucan is believed to depend upon its viscosity in the gut. Factors influencing viscosity include the molecular weight (MW) of the beta-glucan molecule and the amount of soluble beta-glucan in the product, which, in turn determines its concentration (C) in solution. In finished food products both MW and C can be modified by beta-glucanase enzymes present in other ingredients in the food (eg. wheat flour), processing (eg. extrusion) and storage (eg. freezing of moist products such as muffins). The effect of altering the MW and solubility of beta-glucan in foods on glycemic responses has been shown, but a role for MW and C in cholesterol lowering has not been established. To address this issue, this study was designed with 2 primary objectives: 1. An extruded oat cereal containing 3g high-molecular weight oat β-glucan daily will reduce LDL cholesterol compared to a control wheat bran cereal. 2. A significant correlation exists between LDL cholesterol and log(C×MW), where C is the amount of soluble β-glucan in the daily dose of cereal and MW is the molecular weight of the β-glucan in the cereal.

Conditions

• Hypercholesterolemia

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Wheat bran	21g per day of ready to eat breakfast cereal containing wheat bran with 8g of total dietary fiber and 0.5g beta-glucan.
DIETARY_SUPPLEMENT	3g high MW	20.2 grams per day of ready to eat cereal containing 6g total dietary fiber and 3g oat beta glucan with high molecular weight
DIETARY_SUPPLEMENT	4g medium MW	28.5g ready to eat cereal containing 8g total dietary fiber and 4g oat beta glucan with medium molecular weight
DIETARY_SUPPLEMENT	3g medium MW	21.1g of ready to eat cereal containing 6g total fiber and 3g oat beta glucan with a medium molecular weight
DIETARY_SUPPLEMENT	4g low MW	28.7g ready to eat cereal containing 8g total dietary fiber and 4g oat beta glucan with low molecular weight

Timeline

• Start date: 2008-11-01
• Primary completion: 2009-07-01
• Completion: 2009-08-01
• First posted: 2009-09-22
• Last updated: 2011-06-21

Locations

5 sites across 3 countries: Australia, Canada, United Kingdom