A pilot study investigating the effect of Caralluma fimbriata extract on the risk factors of metabolic syndrome in overweight and obese subjects: a randomised controlled clinical trial

Abstract

Central obesity is a key component of metabolic syndrome and it is often associated with other risk factors such as dyslipidemia, elevated plasma glucose levels and elevated blood pressure (BP). In this pilot study, the effect of Caralluma fimbriata (an edible succulent) extract in combination with controlled dietary intake and physical activity on these risk factors was assessed in overweight and obese Australian subjects. This was a randomised, double blind placebo controlled clinical trial. Forty-three adults aged 29-59 years were recruited. The eligibility criteria included a Body Mass Index (BMI) >25 kg/m(2), or a waist circumference >94 cm (male), >80 cm (female). Thirty-three participants completed the 12-week study at Victoria University Nutritional Therapy Clinic. Participants were randomly assigned into two groups. C. fimbriata extract and placebo were orally administered as 500 mg capsules twice daily (1 g/day) and dietary intake and exercise were monitored weekly. The results of thirty-three participants (experimental group, n = 17; placebo group n = 16) were analysed. The primary outcome measure was the decline in waist circumference. By week 9, the experimental group had lost 5.7 cm, compared to only 2.8 cm loss in the placebo group (Difference: -2.890; 95% CI; -5.802 to 0.023). Post intervention, the experimental group had lost 6.5 cm compared to 2.6 cm loss in the placebo group (Difference: -3.847; 95% CI; -7.466 to 0.228). Waist to hip ratio (WHR) also improved significantly after 12 weeks intervention in the experimental group, with a total reduction of 0.03 being recorded compared to 0.01 increase in the placebo group (Difference: -0.033; 95% CI; -0.064 to -0.002). There was also a significant decline in the palatability (visual appeal, smell, taste) of the test meal and sodium intake in the experimental group at week 12 (p < 0.05). In addition a significant reduction in body weight, BMI, hip circumference, systolic BP, HR, triglyceride levels, total fat and saturated fat intake within both groups was observed following the intervention period (p < 0.05). Supplementation with C. fimbriata extract whilst controlling overall dietary intake and physical activity may potentially play a role in curbing central obesity, the key component of metabolic syndrome. Controlling dietary intake and exercise improved body weight and favourably influenced the metabolic risk profile.