Alpha lipoic acid (ALA) is an antioxidant that has been studied for its effects on vascular health, including potential benefits for the arteries. Several clinical and preclinical studies suggest that ALA may support arterial function largely due to its antioxidant and anti-inflammatory properties. ALA can reduce oxidative stress, which is a key contributor to endothelial dysfunction—a precursor to atherosclerosis and other arterial diseases.

Some research indicates that ALA supplementation improves endothelial function, as measured by flow-mediated dilation, in populations at risk of cardiovascular disease, such as those with metabolic syndrome or diabetes. ALA may also improve nitric oxide availability, leading to better vasodilation and blood flow. Additionally, animal and small human studies have shown that ALA can reduce markers of inflammation and oxidative damage, which are linked to arterial stiffening and plaque formation.

However, while the mechanistic rationale is strong and early clinical trials are promising, large-scale, long-term randomized controlled trials in humans are still lacking. Therefore, the scientific evidence is moderate (rated 3 out of 5), with more research needed to fully establish ALA's efficacy for arterial support.