Spirulina Supplementation in Postmenopausal Women

Menopause is defined as the spontaneous and permanent cessation of menstrual bleeding in women due to the loss of ovarian function. The onset of menopause brings about many physiological and psychological symptoms. Certain hormonal changes increase the risk of chronic diseases such as high waist circumference, cardiovascular diseases, obesity, diabetes, and osteoporosis. Spirulina platensis contains approximately 50-70% protein, 15-25% carbohydrates, 6-13% lipids, 4.2-6% nucleic acids, and 2.2-4.8% minerals by dry weight. Polyunsaturated fatty acids (PUFAs) constitute 1.5-2% of the total lipid content. It is rich in essential amino acids (especially leucine, isoleucine, valine), γ-linolenic acid (36% of total FDA), vitamins (thiamine, niacin, riboflavin, pyridoxine, folic acid, cobalamin, C, D and E), minerals (potassium, calcium, chromium, copper, iron, magnesium, manganese, phosphorus, selenium, sodium and zinc), pigments (chlorophyll a, xanthophyll, beta-carotene, echinone, myxoxanthophyll, zeaxanthin, canthaxanthin, diathoxanthin, 3-hydroxyechinone, beta-cryptoxanthin and ossilaxanthin, phycobiliprotein, C-phycocyanin, allophycocyanin) and enzymes (lipase, superoxide dismutase, etc.). Many of the beneficial effects of spirulina on health, which contains powerful antioxidants such as carotenoids, chlorophyll, and phycocyanin, stem from its antioxidant properties. Spirulina supplementation is considered effective as a therapeutic tool in the management of multiple interconnected metabolic abnormalities such as dyslipidemia, glucose intolerance, obesity, and hypertension. This study aimed to investigate the effects of spirulina supplementation on weight gain associated with menopause, changes in metabolic parameters, sleep quality, and markers of depression in mildly obese postmenopausal women.

• Spirulina (Dietary supplement): Participants will receive 2 g/day spirulina tablets for 8 weeks.
• Placebo (Other): Participants will receive matching placebo tablets for 8 weeks.

Primary outcomes

• Fasting Blood Glucose [Baseline and Week 8]: Fasting blood glucose (mg/dL) will be measured at baseline and Week 8 to evaluate the effect of spirulina supplementation.
• HbA1c [Baseline and Week 8]: HbA1c (%) will be measured at baseline and Week 8 to assess long-term glycemic control.
• HOMA-IR [Baseline and Week 8]: Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) will be calculated using fasting glucose and fasting insulin measurements obtained at baseline and Week 8.
• Total Cholesterol [Baseline and Week 8]: Total cholesterol concentration (mg/dL) will be measured at baseline and Week 8.
• LDL Cholesterol [Baseline and Week 8]: Low-density lipoprotein (LDL) cholesterol concentration (mg/dL) will be measured at baseline and Week 8.
• HDL Cholesterol [Baseline and Week 8]: High-density lipoprotein (HDL) cholesterol concentration (mg/dL) will be measured at baseline and Week 8.
• Triglycerides [Baseline and Week 8]: Serum triglyceride concentration (mg/dL) will be measured at baseline and Week 8.

Secondary outcomes

• Body Weight [Baseline and Week 8]: Body weight (kg) will be measured at baseline and Week 8.
• Body Mass Index [Baseline and Week 8]: Body mass index (BMI, kg/m²) will be calculated from measured height and body weight and assessed at baseline and Week 8.
• Waist Circumference [Baseline and Week 8]: Waist circumference (cm) will be measured at baseline and Week 8.
• Hip Circumference [Baseline and Week 8]: Hip circumference (cm) will be measured at baseline and Week 8.
• Mid-Upper Arm Circumference [Baseline and Week 8]: Mid-upper arm circumference (cm) will be measured at baseline and Week 8.
• Waist-to-Height Ratio [Baseline and Week 8]: Waist-to-height ratio will be calculated using waist circumference and height measurements obtained at baseline and Week 8.
• Body Fat Percentage [Baseline and Week 8]: Body fat percentage (%) will be assessed using bioelectrical impedance analysis at baseline and Week 8.
• Body Fat Mass [Baseline and Week 8]: Body fat mass (kg) will be assessed using bioelectrical impedance analysis at baseline and Week 8.
• Total Body Water [Baseline and Week 8]: Total body water (kg) will be assessed using bioelectrical impedance analysis at baseline and Week 8.
• Skeletal Muscle Mass [Baseline and Week 8]: Skeletal muscle mass (kg) will be assessed using bioelectrical impedance analysis at baseline and Week 8.
• The Depression, Anxiety and Stress Scale-21 (DASS-21) [eight weeks]: The Depression Anxiety Stress Scale-21 (DASS-21) is a 21-item self-report questionnaire used to assess depression, anxiety, and stress symptoms. Each item is scored on a 4-point Likert scale ranging from 0 to 3. Higher scores indicate greater psychological distress. Changes in DASS-21 scores from baseline to Week 8 will be evaluated.
• Pittsburgh Sleep Quality Index (PSQI) [eight weeks]: The Pittsburgh Sleep Quality Index (PSQI) consists of a total of 24 questions designed to assess an individual's sleep quality over the past month. Nineteen of these questions are self-report questions answered by the individual; the remaining five are answered by the individual's spouse or roommate. Each component is scored on a scale of 0 to 3. The sum of these component scores yields a total PSQI score ranging from 0 to 21. A score of 0-5 is considered good sleep quality, while a score of 6-21 is considered poor sleep quality.

Sex: Female, ages: 45 Years to 65 Years, accepts healthy volunteers

Inclusion Criteria:

* Volunteering to participate in the study
* Having a body mass index (BMI) between 25 and 29.9 kg/m²
* Having no chronic illnesses
* Being between the ages of 45 and 65
* Being postmenopausal
* Willing to consume the provided supplement
* Individuals who can read and write in Turkish and are open to communication.

Exclusion Criteria:

* Having a chronic condition such as diabetes, hypertension, cancer, metabolic syndrome, chronic kidney disease, dyslipidemia, etc.
* Having a congenital metabolic disorder
* Being in the experimental group but not taking the supplement regularly
* Taking medication to lower blood lipids
* Having an allergy to any food
* Not being in the postmenopausal period