Atopic dermatitis (AD) occurs as a multifactorial long-standing inflammatory skin disease.It has a high incidence globally in all age groups. 

According to the “gut–skin axis” theory, imbalances in the gut can hurt the skin by provoking systemic inflammation and triggering dermatological diseases like AD. 

A study investigated the efficacy of a food supplement carrying selected strains of probiotics in improving AD symptoms and skin conditions.

The study enrolled 80 adult subjects with mild-to-severe AD, skin dryness, desquamation, erythema and itching.

They receive, for 56 days, either a placebo or a mixture of lactobacilli (L. plantarum PBS067, L. reuteri PBS072 and L. rhamnosus LRH020). 

Probiotics were given depending on the patients’ production of post-biotic metabolites and B-group vitamins, anti-inflammatory and antioxidant capacity and anti-microbial activity. 

T0d, T28d and T56d, and then at T84d (after a one-month wash-out) observed Clinical and instrumental dermatological evaluation. Inflammatory cytokine levels from skin near AD lesions were also measured at T0d and T56d.

The following observations were made-

• An improvement in skin smoothness, skin moisturization, self-perception was observed in the subjects receiving the probiotic mixture.
• A decrease in SCORAD index and in the levels of inflammatory markers associated with AD at T28d, with a positive trend up to T56d which was maintained at T84d was observed in the subjects receiving the probiotic mixture. 

It was thus concluded that fast and sustained improvement in AD-related symptoms and skin conditions can be achieved after selected probiotic strains administration.

Michelotti A, Cestone E, Ponti ID, Giardina S, Pisati M, Spartà E, Tursi F. Efficacy of a probiotic supplement in patients with atopic dermatitis: a randomized, double-blind, placebo-controlled clinical trial, European Journal of Dermatology, 2021;31(2): 225-32. DOI : 10.1684/ejd.2021.4019