Written by Tabish Mehraj, PhD, Science Writer. This study demonstrated successful randomization and comparable baseline characteristics between the alpha-lipoic acid and placebo groups. After 12 weeks of supplementation, the ALA group showed significant vascular improvements, including a marked reduction in carotid intima-media thickness (CIMT) and a substantial increase in Flow-Mediated Dilation (FMD) compared to the placebo group. It significantly lowered serum hs-CRP levels; its impact on other inflammatory cytokines, such as TNF-α and IL-6, remained limited.

Alpha-lipoic acid is a well-recognized antioxidant that neutralizes free radicals through its activity as a cofactor of several dehydrogenase enzyme complexes. The alteration of vascular function and structure is associated with coronary artery disease, hypertension, and stroke. Stroke is a condition that causes brain cell death due to improper blood flow and remains the major cause of long-term disability worldwide. Since inflammation and oxidative stress are associated with stroke and vascular disease, alpha-lipoic acid could be a potent antioxidant that improves vascular structure and function.

This double-blinded, randomized, placebo-controlled clinical trial by Vida Mohammadi and his team investigated the effects of an alpha-lipoic acid (ALA) supplement on inflammatory markers and vascular function in individuals who had recently experienced an ischemic stroke. The study specifically aimed to assess the effects of ALA on carotid intima-media thickness (CIMT), Flow-Mediated Dilation (FMD), and inflammatory biomarkers. The study enrolled 80 newly diagnosed stroke patients between 30 and 70 years of age. Participants were grouped to receive either 600 mg of ALA daily or a placebo capsule for 12 weeks. Exclusion criteria included severe chronic diseases, malignancies, use of antioxidant supplements, recurrent stroke, and poor adherence to the intervention. After participant withdrawals and exclusions, 33 patients remained in the ALA group and 34 in the placebo group. The parameters included dietary intake and anthropometric indices.

Key Results/Findings 

Successful Randomization: At Baseline, both the ALA and placebo groups were comparable with respect to dietary, demographic, and clinical characteristics, providing a valid basis for comparison. 

Significant Improvement in CIMT: Patients receiving ALA observed a significant decrease in carotid intima-media thickness (from 0.94 mm to 0.68 mm) vs. baseline, while the placebo group experienced a significant increase in CIMT (P < 0.001). 

Enhanced Endothelial Function: Flow-mediated dilation (FMD) improved substantially in the ALA group, increasing from 6.84% to 18.92% (P < 0.001), whereas the placebo group remained unchanged, suggesting better vascular responsiveness. 

Targeted Anti-Inflammatory Effect: ALA supplementation led to a marked reduction in serum hs-CRP levels (from 14.99 mg/L to 7.24 mg/L) (P < 0.001). 

Limited Impact on Specific Cytokines: While IL-6 showed a non-significant downward trend, effects on TNF-α were generally limited. 

Clinical Implications: The overall improvements in vascular function and endothelial health suggest that ALA may play a crucial role in reducing the risk of recurrent cardiovascular events in patients recovering from an ischemic stroke.

The authors proposed several mechanisms to explain the observed vascular benefits of ALA. ALA may improve endothelial nitric oxide production, thereby enhancing vasodilation and vascular integrity. The study also discussed previous evidence showing that ALA inhibits nuclear factor-kappa B (NF-κB), a transcription factor involved in inflammatory signaling and endothelial dysfunction. Through these antioxidant and anti-inflammatory pathways, ALA may help reduce vascular injury and the progression of atherosclerosis after a stroke.

This study has several strengths. Firstly, the authors used objective, clinically relevant vascular measurements, such as CIMT and FMD, assessed by Doppler ultrasound, thereby increasing the reliability of the outcomes. Secondly, the study focused on newly diagnosed stroke patients, a population at particularly high risk of recurrent vascular events. Despite these strengths, the study also had several limitations. The small population sample size and the per protocol interpretation of data limit the generalizability of the results. The 12-week intervention period may have been too short to detect long-term vascular and inflammatory changes. Another limitation was the lack of assessment of oxidative stress biomarkers, which could have provided additional mechanistic insight into ALA’s antioxidant effects.

Overall, this study demonstrated that supplementation with 600 mg/day of alpha-lipoic acid for 12 weeks significantly improved vascular structure and function and reduced hs-CRP levels in newly diagnosed stroke patients. The findings suggest that ALA is a promising adjunctive nutritional therapy to improve endothelial health and reduce inflammation post-embolic stroke. However, further large-scale, longer-duration clinical trials are necessary to confirm these findings and establish the long-term clinical benefits of ALA supplementation for stroke recovery.

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Posted June 8, 2026.

Dr. Tabish Mehraj is a pharmaceutical scientist with expertise in pharmaceutics, drug delivery, and formulation development. She earned her PhD in Pharmaceutical Sciences from the University of Mississippi, where her research focused on the formulation, optimization, and characterization of lipid-based nanocarriers for targeted liver delivery of antimalarial therapeutics. Dr. Mehraj has also served as an ORISE Fellow at the U.S. Food and Drug Administration (FDA), where she evaluated the effects of formulation and process design on the quality and performance of intravaginal drug delivery systems and developed bio-relevant in vitro drug release testing methods. She has teaching experience in pharmaceutical and life sciences courses and has authored peer-reviewed publications, book chapters, and conference presentations. Dr. Mehraj is an active member of the American Association of Pharmaceutical Scientists and has been recognized by honor societies including Rho Chi and Gamma Beta Phi.

References: 

1. Mohammadi, V., Aghababaee, S. K., Khorvash, F., Dehghani, S., & Askari, G. (2025). The effect of alpha-lipoic acid supplementation on vascular function and inflammation in patients with newly experienced stroke. Journal of Research in Medical Sciences, 30(1), 61.