The effect of L-carnitine supplementation on blood pressure in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled trial

Diabetic patients with hypertension are at a high risk of cardiovascular complications. The present study made an attempt to determine the effect of oral L-carnitine supplementation on blood pressure in patients with type 2 diabetes mellitus (T2DM). In this randomized, double-blind, placebo-controlled trial, 70 patients with T2DM at the age range of 41–75 years were randomly allocated to two groups: L-carnitin group (LG) (n = 35) receiving 1000 mg/day L-carnitin, and placebo group (PG) (n = 35) receiving 1000 mg/day wheat starch as placebo for 12 weeks. The systolic and diastolic blood pressures, mean arterial blood pressure and pulse pressure were examined before and after the intervention. Sixty-four participants completed the study. At the end of the study period, LG compared with the PG, showed no significant difference in SBP (−1.14 ± 2.45 mmHg vs. −2.42 ± 2.79 mmHg), DBP (−3.2 ± 1.94 mmHg vs. −6±2.30 mmHg), MAP (−2.51 ± 1.84 mmHg vs. −4.80 ± 2.11 mmHg) and PP (2.05 ± 2.23 mmHg vs. 3.57 ± 2.73 mmHg). The oral supplementation of L-carnitine 1000 mg/day fails to affect blood pressure after 12 weeks of treatment in diabetes patients. *This was a randomized, controlled clinical trial (RCT) which was registered October 28, 2017 in the Iranian Registry of Clinical Trials (http://www.irct.ir, identifer: IRCT2017100936681N1). •L-carnitine could not improve blood pressure.•The effect of L-carnitine supplementation on MAP and PP is unclear.•L-carnitine does not affect on SBP and DBP in diabetic patients.