About PHGG
PHGG is a soluble, fermentable fiber made by enzymatically hydrolyzing guar gum to reduce viscosity while retaining prebiotic effects. Multiple RCTs support 5-10 g/day for improving IBS symptoms (bloating, stool regularity) and chronic constipation over 6-12 weeks, with good tolerability. Fibre4 (Webber Naturals) is a single-ingredient PHGG product.
What PHGG supports
- May improve bloating, regularity, and IBS symptoms — supported by multiple randomized controlled trials at 5-10 g/day
How much PHGG to take
The RDA prevents deficiency. The effective range is what clinical trials used to actually move the outcome.
Effective
5–10
g
5-10 g/day is the range used across RCTs for IBS symptoms, bloating, and constipation, generally titrated up from a lower starting dose over 1-2 weeks.
Clinical evidence
Moderate clinical evidence. Multiple RCTs support efficacy for IBS/constipation symptoms at 5-10 g/day; well-tolerated soluble fiber.
NIH Fact Sheet