Menopause is a stage characterized by the sudden decrease in estrogens linked to the absence of amenorrhea for at least 12 months. Estrogens are involved in certain metabolic pathways such as lipids metabolism and the distribution of body fat in the body. As a result of the fall of estrogen production, postmenopausal women experience a number of alterations of the energy homeostasis that are accompanied by an increase in body weight and a tendency to obesity and visceral fat deposition, as well as variations in the levels of total cholesterol (T-C), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TGs), increasing the risk for cardiometabolic diseases. In addition, menopause contributes to disorders of the glucose metabolism increasing insulin resistance (IR) that can predispose to the development of type 2 diabetes mellitus (T2DM).
(Poly)phenols are recognized as bioactive compounds with general antioxidant and anti-inflammatory activity and as potent vasodilators and stimulators of the immune response with the capacity to modulate a range of cardiovascular and metabolic risk factors. An increasing number of intervention studies have built up the evidence of the cardiovascular and metabolic benefits of the intake of these compounds in humans, however, the results remain limited and contradictory, leading to the current controversy regarding the consistency and magnitude of the protective effects that these compounds exert in humans. The lack of consistent and significant results may be partially due to the heterogeneity of the studies and the interindividual variability of the participants.
The investigators have designed this intervention to clearly described the effects of the (poly)phenolic compounds in postmenopausal women with a well-characterized cardiometabolic status. The observed beneficial effects will be correlated with the absorption and metabolism of these compounds.
The protocol will be a single arm intervention study with 22 postmenopausal women as a participants. Prior to start the intervention (initial time of the study) the volunteers will follow their habitual diet during 30 days as a control period. Immediately, they will start with the intervention period (baseline) following their habitual diet supplemented with (poly)phenol rich products, eating daily 100 ml of a commercial juice of berries and pomegranate, 20 g dark chocolate and 1 green tea, during 60 days (after intervention).
At the beginning of the study (initial time), at the beginning of the intervention (baseline) and at the end of the intervention (after the intervention) with rich (poly)phenols foods, biological samples (blood, urine and feces) and anthropometric measurements will be taken. In addition, the participants will record the food intake weekly with a 24 h dietary-recall form.
The investigators will evaluate followed parameters: 1) glucose metabolism indicators, i.e. glucose, insulin and Homeostatic Model Assessment of IR (HOMA-IR), 2) lipid profile (T-C, LDL-C, HDL-C and TGs), 3) blood pressure, both, systolic blood pressure (SBP), and diastolic blood pressure (DBP), 4) biomarkers of inflammation, CRP, TNF-α, adiponectin, soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular adhesion molecule 1 (sICAM-1), 5) biomarkers of oxidative stress: oxidized isoprostanes and malonaldehyde (MDA), 6) body mass index, body fat and waist-to-hip ratio, 7) dietary habits (total energy intake and macronutrient distribution), 8) metabolites and catabolites of (poly)phenols, and 9) changes in the microbiota.
