The components of metabolic syndrome include high levels of serum glucose and triglycerides (TGs), low levels of high-density lipoprotein cholesterol (HDL-C), high blood pressure (BP), and abdominal obesity. Metabolic syndrome increases the risks of cardiovascular disease and diabetes. The stigma of saffron (Crocus sativus, Iridaceae) has been used medicinally for its antidepressant, sedative, antispasmodic, respiratory, decongestant, and expectorant properties. Its main active metabolites are crocin, picrocrocin, and safranal. Some research indicates that it may affect the biological parameters defining metabolic syndrome. These authors conducted a double-blind, randomized, placebo-controlled clinical trial to evaluate the effects of crocin consumption on patients with metabolic syndrome.
The study was conducted between March 2010 and March 2011 and included patients referred to the Cardiac Outpatient Cardiology Clinic at Birjand University of Medical Sciences in Birjand, Iran. The patients had been diagnosed with metabolic syndrome as defined by the International Diabetes Federation, including central obesity (waist circumference > 37 inches [94 cm] in men and greater than 31.5 inches [80 cm] in women) and two of the following: HDL-C <40 mg/dL in men and <50 mg/dL in women; previously diagnosed type 2 diabetes mellitus or elevated fasting blood sugar (FBS) ≥100 mg/dL; drug treatment for hypertension or elevated BP (systolic BP ≥130 mm Hg or diastolic BP ≥85 mm Hg); and TGs ≥150 mg/dL or specific treatment for hypertriglyceridemia.
Saffron stigmas, which were obtained from Novin Zaferan Co., had been collected from Ghaen in South Khorasan Province, Iran. At one point it is stated that tablets were prepared with crocin content of saffron extract measuring 19.7 (~20) mg per 100 mg of saffron extract. Each tablet contained 100 mg of crocin. However, it is also stated that tablets were made with purified crocin and weighed a mean of 400 mg, with 20% (=80 mg) being crocin and the remainder starch. Placebo tablets containing starch and artificial coloring were similar in size and color to the crocin tablets.
Sixty patients were randomly assigned to take one tablet of crocin or placebo daily for six weeks, during which they were not supposed to change their lifestyle. Of those 60 patients, 24 in each group completed the study. Reasons for patient dropouts were not provided. The mean age of the patients was 53.8 ± 9.2 years in the crocin group and 50.9 ± 8.8 years in the placebo group. The number of women totaled 21 in the crocin group and 20 in the placebo group. No significant between-group differences in baseline characteristics were observed. All patients underwent a diagnostic interview and medical history at baseline. Height and weight were measured, and body mass index (BMI) was calculated. Waist, hip, and thigh circumferences were measured. Waist-to-hip and waist-to-thigh ratios were calculated. All patients had blood drawn after a 12-hour overnight fast to measure FBS and serum lipids. All measurements were done at baseline and after six weeks of intervention.
After six weeks, significant reductions were seen in the crocin group in total cholesterol (P<0.001) and TG (P=0.003) levels compared with baseline. In the control group, cholesterol levels decreased significantly compared with baseline (P=0.01). No other significant changes in outcome measures were seen in either group compared with baseline, and the between-group differences were nonsignificant. Crocin was well-tolerated, with no adverse effects reported.
Unlike some earlier studies, this trial reported no change in blood pressure or BMI after six weeks of crocin treatment. The authors hypothesize that their findings may have been limited by the “quantity of saffron consumed or duration,” suggesting that future studies use higher dosages for longer periods of time. However, it is also worth noting that the tested substance was largely purified crocin rather than a traditional saffron extract, which could have superior activity. Other limitations of the study include the small sample size and confounding factors such as dietary intake and physical activity, which were not controlled.
Although the findings indicate that crocin consumption may change some laboratory parameters, the “dosage used in our study had no effect on the components of metabolic syndrome,” write the authors.
The authors state that they have no conflicts of interest.
Kermani T, Kazemi T, Molki S, Ilkhani K, Sharifzadeh G, Rajabi O. The efficacy of crocin of saffron (Crocus sativus L.) on the components of metabolic syndrome: A randomized controlled clinical trial. J Res Pharm Pract. October-December 2017;6(4):228-232. doi: 10.4103/jrpp.JRPP_17_26.