Effect of oral cinnamon intervention on metabolic profile and body composition of Asian Indians with metabolic syndrome: a randomized double -blind control trial

Randomized, double-blind, placebo-controlled trial in treatment-naive Asian Indian adults with metabolic syndrome recruited from a private hospital and clinic in South Delhi, India. The cinnamon arm included 58 participants randomized 1:1 with placebo; 13 participants dropped out overall, including 6 from the cinnamon group.

Oral cinnamon was given at 3 g/day for 16 weeks as six 500 mg capsules daily, taken as two capsules after breakfast, lunch, and dinner. The active regimen was compared with placebo in a double-blind trial.

Cinnamon produced overall favorable effects on metabolic syndrome features and the authors concluded it may be a cost-effective dietary intervention. Compared with placebo, cinnamon significantly improved fasting blood glucose, HbA1c, total cholesterol, triglycerides, HDL, systolic blood pressure, and diastolic blood pressure; for example, adjusted between-group differences were 0.3 mmol/L for FBG, 2.6 mmol/mol for HbA1c, 0.42 mmol/L for total cholesterol, 0.20 mmol/L for triglycerides, 8.3 mmHg for systolic BP, and 6.9 mmHg for diastolic BP. Postprandial glucose also improved after adjustment (difference 0.6 mmol/L, p=0.030). At 16 weeks, metabolic syndrome prevalence was 34.5% in the cinnamon group versus 5.2% in the placebo group, and no harmful effects were reported. The authors reported that larger and longer trials are needed.

The trial was relatively small, short in duration, and conducted in a single North Indian setting, which limits generalizability. Some outcomes were not fully reported at follow-up in the extracted table, and longer-term efficacy and safety remain uncertain.