# Low-dose of yeast beta-glucan on respiratory symptoms and psychological well-being in moderately stressed adults

## TL;DR

A 12-week study found that yeast beta-glucan, especially at a moderate dose, may help reduce respiratory symptoms and improve mood in moderately stressed adults.

## Contribution

This study provides new evidence on the optimal dose of yeast beta-glucan for respiratory and psychological benefits in stressed adults.

## Key findings

- Yeast beta-glucan reduced upper respiratory tract infection symptom severity compared to placebo.
- Moderate-dose yeast beta-glucan improved mood and vitality in moderately stressed adults.
- Yeast beta-glucan was safe with no adverse effects on metabolic biomarkers.

## Abstract

Yeast beta-glucan (YBG) is an immunomodulatory polysaccharide that enhances host defense, but optimal dosing for respiratory and psychological benefits requires investigation. This 12-week randomized, double-blind, placebo-controlled trial (ISRCTN 48336189) enrolled 198 moderately stressed adults (PSS-10 scores: 14–26) assigned to placebo, low-dose YBG (120 mg), or moderate-dose YBG (204 mg) daily. The primary outcome was upper respiratory tract infection symptom severity measured by WURSS-21. Both YBG doses improved symptoms compared with placebo (adjusted mean change, 95% CI: placebo +3.42 [0.91 to 5.93]; 120 mg −2.27 [−4.82 to 0.28]; 204 mg −3.51 [−6.06 to −0.96]), with only 204 mg exceeding the minimal clinically important difference. Both doses reduced negative mood states (p < 0.001), with no safety concerns observed. These findings suggest that YBG may support respiratory and emotional health in stressed populations, with 204 mg demonstrating the most consistent clinically meaningful effects.

•Yeast beta-glucan reduced URTI symptom severity•Moderate-dose yeast beta-glucan improved mood and vitality•Yeast beta-glucan was safe with stable metabolic biomarkers

Yeast beta-glucan reduced URTI symptom severity

Moderate-dose yeast beta-glucan improved mood and vitality

Yeast beta-glucan was safe with stable metabolic biomarkers

Health sciences; Medicine; Psychiatry; Psychology