Effect of Nordic Berries on Cognitive Function, Cardiometabolic Risk Markers and Gut Microbiota in Adults With Mild Cognitive Impairment

Inclusion Criteria: 1. Age of 55 years or older. 2. Cognitive impairment in accordance with the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 criteria and global deterioration scale (GDS) stage 3. 3. Capable and willing to give written informed consent. 4. Capable and willing to perform cognitive testing (mastering the Swedish language, functional vision and hearing or the use of visual or hearing aids during testing). 5. Capable and willing to ingest the study beverage for 12 weeks and to follow the instructions given. Exclusion Criteria: 1. MMSE (Mini-Mental State Examination) \<24 (at screening or in the last 3 months). 2. Cognitive disease (e.g. dementia) according to Global Deterioration Scale (GDS) stage 4 and up. 3. Severe affective disorder with current symptoms 4. Severe mental disorder. 5. Newly diagnosed or poorly regulated thyroid disease (unstable dose since 3 months back). 6. Ongoing insulin therapy. 7. Ongoing treatment for malignancy\*. 8. Conditions with major impact on the gastrointestinal tract (such as Crohn's disease, ulcerative colitis, diagnosed gluten intolerance, undertaken intestinal resection or weight loss surgery). 9. Planned major intervention in health care over the next 3 months (the study period). 10. Undergoing antibiotic therapy for the last 3 months prior to inclusion in the study. 11. Allergy / intolerance to berries or other ingredients in the study products (i.e., colorants, aromas, starch). 12. Vegetarians / vegans. 13. Smoking. 14. Abuse of alcohol or psychoactive substance. 15. Significant change in medication over the last 3 months. 16. Daily, regular high consumption of berries or juices / marmalade / product with high content of these berries (guideline no more than 5 grams per day). (Can be recruited for the study if this intake ceases before visit 1. High consumes (approximately 1 dl of berries per day) has to cease with this at least one month before visit 1.) 17. Taking supplements with potential cognitive effects (e.g. omega-3, ginko biloba), or containing grape and berry extracts or probiotics (capsules or other). (Can be recruited if this intake ceases at least one month before visit 1). 18. Planned longer absence/vacation during the next 3 months (the study period). 19. Concurrent participation in other clinical intervention trials (dietary/pharmacological). 20. Other reasons that make the Study investigator in consultation with the responsible physician deem the person inappropriate to include. * basalioma exempt from exclusion criteria.