Overview

Dietary fat plays a crucial role as a modifiable risk factor influencing both non-fasting lipaemia and vascular reactivity. Notably, the intake of dietary saturated fatty acids (SFAs) has been associated with adverse effects on blood lipid profiles, whereas increased consumption of unsaturated fatty acids (UFAs) has shown potential to improve lipid health. Pomegranate seed oil (PSO) stands out due to its high content of conjugated α-linolenic acids (CLnAs). However, research comparing the impact of these fatty acids on postprandial vascular function, particularly in postmenopausal women, remains limited. A cross-over, single-blind, randomised acute postprandial study will be conducted in 15 healthy postmenopausal women. Participants will be assigned to consume the test meals either a placebo (50 g of mixed fat; 4:0.5:0.5 palm oil: rapeseed oil: safflower oil) or PSO (40 g of mixed fat and 10g of PSO) in random order on 2 separate occasions, with 4-6 weeks between each study visit. The anthropometric, blood pressure, and arterial stiffness, will be taken for each study visit. Blood samples will be collected for the measurement of fasting lipids, glucose, insulin, inflammatory markers, and whole blood culture. The findings from this study will contribute to the evidence base on how consuming meals rich in PSO influence the level of blood lipids as well as other biomarkers for cardiovascular disease.

Eligibility

Inclusion Criteria:

• Postmenopausal women who have been postmenopausal for at least 12 months.
• Aged 65 and under years
• Serum TAG < 2.3 mmol/l
• Body mass index (BMI) between 18-35 kg/m2
• Fasting total cholesterol < 7.5 mmol/l
• Fasting glucose concentration <7 mmol/L

Exclusion Criteria:

• Smokers
• Medical history of myocardial infarction or stroke in the past 12 months
• Diabetes (defined as fasting glucose > 7.0 mmol/l) or other endocrine disorders
• Kidney, liver, pancreas or gastrointestinal disorder
• Hypertension (blood pressure > 140/90 mmHg), cancer, medication for hyperlipidaemia (e.g. statins), hypertension or, inflammation
• Anaemia (<115 g/L haemoglobin)
• Taking any dietary supplements known to influence lipids/gut microbiota (e.g. plant stanols, fish oil, phytochemicals, natural laxatives, probiotics and prebiotics)
• Drinking in excess of 14 units of alcohol per week
• Planning on a weight-reducing regime
• Parallel participation in another dietary intervention study
• Any other unusual medical history or diet and lifestyle habits or practices that would preclude volunteers from participating in a dietary intervention and metabolic study