Satiety effects of psyllium in healthy volunteers

Controlling hunger between meals is a challenge for many individuals. This manuscript comprises 2 sequential clinical trials investigating the effects of psyllium (Metamucil) on satiety, both using a randomized, double-blind, placebo-controlled cross-over design. The first study determined the effects of 3.4 g, 6.8 g, and 10.2 g of psyllium taken before breakfast and lunch for 3 days. The second study determined the effects of 6.8 g (taken before breakfast and lunch on Days 1 and 2 and before breakfast on Day 3) on the satiety of participants receiving an energy restricted meal in the morning (breakfast) for 3 days. Efficacy endpoints were mean inter-meal hunger, desire to eat, and Satiety Labeled Intensity Magnitude Visual Analog Scale scores. In Study 1, all 3 psyllium doses resulted in directional or statistically significant mean reductions in hunger and desire to eat, and increased fullness between meals compared to placebo, with both higher doses better than placebo or 3.4 g. The 6.8 g dose provided more consistent (p ≤ 0.013) satiety benefits versus placebo. In Study 2, satiety was assessed similarly to Study 1. A significant (p ≤ 0.004) decrease in the 3-day mean hunger and desire to eat, as well as an increase in fullness for psyllium relative to placebo was observed. Most adverse events were mild gastrointestinal symptoms and were similar for psyllium compared to placebo. These results indicate that psyllium supplementation contributes to greater fullness and less hunger between meals.