Could a simple fat swap reshape your gut bacteria and protect your heart?

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

Inclusion Criteria: 1. Postmenopausal women (defined as complete natural cessation of menses for \>12 months or a bilateral oophorectomy), who are not currently using hormone replacement therapy (HRT) or gender-affirming hormone treatments 2. Age \>50 years 3. BMI \>20 to \<35 kg/m2, inclusive 4. Non-smoker or former smoker who quit \> 6 months 5. Normotensive with or without medication 6. Normal gastrointestinal function with regular bowel movements at least once every other day 7. Willingness to swallow the mini-pills 8. Willingness to collect and return multiple stool samples 9. Adequate refrigerator and freezer space to store study meals 10. Intent to remain in the greater Boston area during the intervention periods Exclusion Criteria: 1. Allergy/intolerance/religious reasons to avoid study meals or food ingredients 2. Regular use of dietary supplements, pre/probiotics, laxatives or fiber supplements (except multivitamins) within the past 3 months 3. Use of steroids (excluding topical) within the past 3 months 4. Regular use of aspirin (except baby aspirin), NSAIDS, or anti diarrheal medication 5. Current smokers or former smokers who quit \< 6 months ago, and use of nicotine replacement products within the last 6 months 6. Chronic constipation 7. Use of oral antibiotics within the past 3 months. 8. Use of dental prophylaxis within the past 3 months 9. Regular use of stomach acid lowering and weight loss medications such as GLP-1 agonists 10. Planned colonoscopy 3 months prior to or during the study period 11. Swallowing disorder or inability or difficulty taking pills 12. Malabsorptive and inflammatory bowel disease, diverticulosis, and history of diverticulitis, gastric esophageal/intestinal surgery, including lap banding or bariatric surgery. 13. History of bowel obstruction, gallstones, gastroparesis, pancreas and liver/gallbaldder disorders. 14. Any form of active substance abuse or dependence (including drug or alcohol abuse). 15. Established major chronic diseases such as CVD, diabetes, active cancer within the last 5 years, or any significant medical condition at the study MD's discretion 16. A clinical condition that, in the judgment of the study MD or PI, could potentially pose a health risk to the subject while involved in the study. 17. Unwillingness to adhere to study protocol 18. Intent to increase or decrease body weight during the study period 19. No Social Security number (for payment and IRS forms). 20. Individuals who directly report to any member of the research team.