Could a daily probiotic help protect aging brains?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Men and women aged between 60 and 85 years. * Present "Mild Cognitive Impairment" (MCI) based on: * MoCA test (\< 26 points) or score adjusted for educational level * and CDR test (≤ 0.5 points) * Maintain functional capacity according to the (I)ADL test (≥ 70 points) * Show "cognitive concern" reported by the participant and/or a surrogate caregiver * Demonstrate longitudinal decline in cognitive function (progressive and not stabilized) for more than 3-5 years. * BMI ≥ 20 and \< 30 kg/m² * Absence of a family or social environment that prevents treatment adherence. * Adequate cultural level and understanding of the clinical study. * Agree to participate voluntarily in the study and provide written informed consent. Exclusion Criteria: * Subjects with severe neurological or psychiatric disorders due to any of the following causes: severe dementia, depression, epilepsy, schizophrenia, or bipolar disorder. * Subjects who have suffered a severe stroke prior to the study (FAZKAS=3) * Subjects with a history of malignancy \< 5 years (\< 5 years if the brain was affected) * Subjects who have experienced severe traumatic brain injury with structural brain injury and/or prior brain surgery * Subjects with pacemakers and those with metal implants that may interfere with EEG or MRI * Subjects treated with medications: benzodiazepines, neuroleptics, narcotics, anticonvulsants, or sedative-hypnotics in the last 3 months * Subjects who have been treated with antibiotics or probiotic supplements at least 3 months before the start of the study. * Subjects with hearing or visual impairments that prevent the evaluations included in the study * Subjects with severe illnesses affecting nutritional status (liver, kidney, etc.) * Subjects who have engaged in weight loss diets or significant dietary changes in the 8 weeks prior to starting the study * Subjects with high alcohol consumption (\> 3 alcoholic beverages per day)