The effect of probiotics on the gut-brain axis in children with attention deficit hyperactivity disorder will be studied.

Inclusion Criteria:

• Males and females aged 8 - 11 years
• With mild ADHD symptoms
• Patient and parents (legal representatives) able and willing to participate in the research by complying with the protocol procedures

Exclusion Criteria:

• Metabolic disorder
• Severe chronic disease
• GI disorders found to be inconsistent with the conduct of the study by the investigator
• Neurological disorder involving central function (e.g., intellectual disability, autism spectrum disorder, epilepsy, narcolepsy)
• Currently treated with a medication with primary central nervous system activity or major psychiatric condition requiring hospitalization
• With a known or suspected food allergy or intolerance or hypersensitivity to any of the study products' ingredients
• Having taken prebiotic or probiotic treatment in the month prior to inclusion, or having taken antibiotics for more than one week in the 3 months prior to inclusion,
• Taking part in another clinical trial or being in the exclusion period of a previous clinical trial,
• Parents (legal representatives) presenting a psychological or linguistic incapability to sign the ICF,
• Parents (legal representatives) impossible to contact in case of emergency.