Abstract
Dietary fiber-rich diets are gaining popularity as an alternative therapy for skin health. Plant-based prebiotic partially hydrolyzed guar gum (PHGG) dietary fiber promotes gastrointestinal health, which is imperative for skin health through the gut microbiome. In this randomized, double-blind, and placebo-controlled study, the purpose was to assess the therapeutic effects of PHGG on skin hydration, trans-epidermal water loss (TEWL), and skin viscoelastic properties during the winter season. Healthy male and female subjects (n= 70; M9 & F61; mean age: 45.5 ± 8.1 years) were recruited. They received either the 5 g PHGG dietary fiber (n= 35) or a 5 g placebo (n= 35) for twelve weeks. Skin stratum corneum hydration level (skin moisture), TEWL, skin elasticity parameters, skin color variation, and skin quality and condition were assessed using non-invasive characterization methods at baseline (T0), after 6 weeks (T6), and 12 weeks (T12) as well as questionnaires to evaluate the sustainability of the induced changes to support the study outcomes. The results confirmed that soluble PHGG prebiotic dietary fiber can help improve skin conditions throughout the winter season by restoring skin hydration (p ≤ 0.05), reducing trans-epidermal water loss (p ≤ 0.05), and improving skin texture and elasticity parameters (p ≤ 0.05). After 6 weeks of PHGG dietary fiber intake, there was a substantial decrease in TEWL (p = 0.042*) and continuing improvement in viscoelasticity metrics (p ≤ 0.05) when compared to placebo. Also, a significant relationship (Spearman's correlation; p = 0.048*) between increased skin hydration and reduction of trans-epidermal water loss was observed. Subject satisfaction with efficacy reflected these encouraging findings, and the PHGG dietary fiber was well tolerated, with no adverse events occurring during the study period.
