A randomized, double-blind, placebo-controlled, multi-center, parallel group study on overweight and obese individuals following healthy lifestyle consisting of calorie-reduced diet (20% calorie restriction) and increase in daily activity (1000 steps more per day once compared to the baseline steps)

Inclusion Criteria:

1. Voluntary, written, signed, informed consent to participate in the study
2. Male or female, age between 20 to 65 (inclusive)
3. BMI between 28.0 and 34.9 (inclusive), of which 1:1 overweight (28.0-29.9):obese (30-34.9)
4. Waist circumference for men of > 102 cm or for women of > 88 cm
5. Agreement to comply with the protocol and study restrictions
6. Access to Internet in addition to willingness and ability to use web-based questionnaires
7. Available for all study visits
8. Females of child-bearing potential required to provide a negative urine pregnancy test and agree to use a medically-approved method of birth control, eg. all of the following are approved: birth control pill, patch, shot, vaginal ring, mini pill, long-acting reversible contraception (LARC) meaning hormonal intrauterine device, nonhormonal intrauterine device with copper, subdermal contraceptive implant, condoms, cervical cap, diaphragm.
9. Covered by Health Insurance System and / or in compliance with the recommendations of National Law in force relating to biomedical research.

Exclusion Criteria:

1. Diagnosed and pharmacologically-treated type 1 and type 2 diabetes (fasting blood glucose ≥ 7 mmol/l)
2. Use of medication/supplements for blood glucose control
3. Pharmacologically-treated (medication/supplements) hypertension or dyslipidemia
4. Cardiovascular disease, hypertensive retinopathy, left ventricular dysfunction, secondary hypertension, liver dysfunction/disease, kidney dysfunction/disease, dementia, thyroid disease, pancreatic disease, history of cancer within past 5 years (excluding basal cell carcinoma), anemia, or any other disease or condition which, in the Investigator's opinion, could interfere with the results of the study or the safety of the subject
5. Use of drugs or supplements to manage body weight or body fat in the last 3 months
6. Use of laxatives or fiber supplements in the past 6 weeks.
7. History of chronic active inflammatory disorders
8. History of bariatric surgery
9. History of any chronic gastrointestinal disease (e.g. IBD) or disorders (e.g. IBS, constipation, diarrhea), or gastrointestinal reflux disease
10. Regular use of non-steroidal anti-inflammatory drugs, systemic or inhaled corticosteroids, or systemic immunomodulatory drugs
11. Regular (more than once per week) use of proton pump inhibitors
12. Recent (last 3 months) or ongoing antibiotic use
13. Immunosuppression or ongoing therapy causing immunosuppression
14. Use of probiotic supplements during the previous 6 weeks
15. Significant change in tobacco, snuff, nicotine and e-cigarette use habits in the past 3 months or planned cessation of the use of these products during the trial
16. Use of vitamin D supplementation of ≥100 µg/day
17. Active or recent (last 3 months) participation in a weight loss program (diet and/or exercise)
18. Weight change (increase or loss) of 3 kg during the past 3 months
19. Pregnant or planning pregnancy during the study or breastfeeding
20. Participation in a clinical trial with an investigational product or drug within 60 days prior to screening
21. Likeliness to be noncompliant with the protocol
22. No possibility of contact in case of emergency
23. Illicit drug users
24. Alcohol abusers
25. Administrative or legal supervision
26. Subject who would receive more than 4500 euros as indemnities for his participation in biomedical research within the 12 last months, including the indemnities for the present study
27. Other reasons that, in the opinion of the Investigator, make the participant unsuitable for enrolment
28. Other reasons that, in the opinion of the Investigator, make the participant unsuitable for enrolment