Effect of a Postbiotic Intake on Glucose Control and Microbiota Composition of Type 2 Diabetic Subjects: a Randomized Controlled Trial.

Inclusion Criteria:

• Men and women aged between 18 and 70 years.

• Subjects diagnosed with DM2: glycosylated hemoglobin (HbA1c) ≥6.5% and/or basalglucose ≥126 mg/dL. Debut time will not be taken into account.

• Body Mass Index (BMI) between 25 and 39.9 kg/m2.

• Treatment for DM2/stable lifestyle, as well as other treatments for otherpathologies (stable at least 3 months prior to the start of the intervention).

• Stable baseline HbA1c or glucose value for at least 3 months before starting theintervention.

• No weight variations (± 5%) during the last 3 months.

• Subjects must be in general physical and psychological conditions that theresearcher assesses in accordance with the objective of the study.

• Subjects must be able to understand and be willing to sign the informed consent, andmust comply with all study procedures and requirements.

Exclusion Criteria:

• Subjects who have received oral antibiotic treatment in the 45 days prior to thestart of the study.

• Patients who have started hypoglycemic treatment, especially in the 3 months priorto inclusion. Insulin treatment.

• Severe untreated dyslipidemia, hypertension or hypothyroidism, or treated for lessthan 3 months.

• Presence of relevant functional or structural anomalies of the digestive system,such as malformations, angiodysplasias, active peptic ulcers, chronic inflammatorydiseases or malabsorption.

• Subjects who have undergone surgical interventions of the digestive system withpermanent consequences (for example, gastroduodenostomy).

• Suffer from any type of cancer or be undergoing treatment for it, or a period ofless than 5 years since its eradication.

• Subjects who work rotating shifts that include night shifts.

• Presence of some type of psychological impediment such as depressive pathology,anxiety, untreated bipolar disorder. They will be able to participate if they havethe disease but with stable treatment for at least 3 months prior to the start ofthe trial.

• Have an allergy or intolerance to any food or food group that is likely to manifestduring the study.

• Be on a special diet during the 3 months prior to the start of the study, except fortreatment for DM2, in this case, the lifestyle/diet will have to be stable in the 3months prior to the start of the study.

• Weight variations (± 5%) during the last 3 months.

• Suffer from eating disorders or present restrictive behaviors in their diet. Scoreon the EAT-26 questionnaire equal to or greater than 20.

• Subjects who have undergone surgical treatment for obesity.

• Be pregnant or breastfeeding.

• Present alcohol abuse (more than 14 units/day in women and 20 units/day in men)and/or drugs.

• Show poor collaboration or have difficulties to follow the study procedures.

• Take some type of nutritional supplementation that can affect blood glucose and/orthe microbiota. If they take it, in order to be included in the study, they willhave to stop the supplement, with a washout period of at least 14 days beforestarting the study.