Poor regulation of lipid metabolism and hyperlipidemia are central to the development of cardiovascular disease (CVD). Hyperlipidemia is characterized as the overproduction of very low density cholesterol and low density lipoprotein (LDL) (i.e. bad cholesterol) and decreased high density lipoprotein (HDL) (i.e. good cholesterol). Amongst individuals with mild to moderate hyperlipidemia, lifestyle changes is the first treatment option, such as a healthy diet. Therefore, seeking to develop food-based approaches for hyperlipidemia therapy is a timely endeavour. Fenugreek has been suggested as an attractive option, as it is a spice throughout the world which possesses medicinal properties in regulating human nutrient metabolism. In a recent review of the overall effects of fenugreek on hyperlipidemia in humans with diabetes and prediabetes, this analysis suggested that fenugreek has total cholesterol-lowering efficacy. The effects of fenugreek on triglyceride and LDL-cholesterol showed a trend towards reduction and an incremental trend for HDL-cholesterol but needed further confirmation. The effect of fenugreek in human subjects with hyperlipidemia without diabetes has not been investigated. This research aims to investigate the lipid-lowering effect of fenugreek seed consumed as a tea in patients with hyperlipidaemia, but without diabetes over an 8-week intervention period. Changes in plasma microRNAs will be analysed to establish non-invasive therapeutic biomarkers of hyperlipidemia.
Participants without pre-existing CVD or diabetes aged 18-70 years old will be included if they have hyperlipidemia (plasma triglyceride level between 1.7 - 4.5mmol/l) not on any lipid-lowering treatment or on a stable lipid-lowering treatment (last six months) but still have confirmation of high triglycerides within the range required for study.
114 participants will be randomized into two groups (57/group) to receive either fenugreek seeds or control tea, respectively. Treatment allocations will be placed into sealed envelopes and this will be opened at the baseline study visit with the participant.
Fenugreek seeds will be delivered at a dose of 5g/day, drunk as a tea (2.5g/per tea bag), p.o. twice a day at a 12-hour interval) for 8 weeks (56 days). The tea bags will be brewed in a cup (200ml) of boiled hot water for 10 minutes before drinking. This will be self-administered by the subjects, twice a day at a 12-hour interval. The rationale for choosing the dose and intervention time course were based on the previous studies where metabolic effects have been detected. Literature reports from 12 human studies on diabetic and pre-diabetic subjects gave doses of fenugreek seed ranging from 1 to 100g/day, with the median treatment dose being 6.3g/day, to the participants; the intervention time course ranged from 1 week to 3 years, with the median treatment time being 60 days. The dose and duration in this study was therefore designed as being similar to these studies where metabolic effects have been detected, and also, where participant burden will not be too onerous, at a dose of 5g/day, twice a day at a 12-hour interval for 8 weeks (56 days). For the control group, a control black tea (2.5g/bag), self-administered by the subjects, twice in a day at a 12-hour interval. Black tea is a type of fermented tea that has been found to possess much less cardioprotective and lipid profile improving effect compared to green tea due to the different manufacture process. Consumption of black tea has been found not associated with a reduced risk of coronary heart disease in the United Kingdom.
Recruitment will be via outpatient hyperlipidemia clinics, primary care and advertisements. Study visits will take place at the Centre for Public Health at baseline, 4 and 8 weeks and will involve the collection of demographic information, anthropometric measurements, blood pressure and fasting blood samples.
