Flax fiber, commonly derived from the seeds of the Linum usitatissimum plant, is rich in dietary fiber and bioactive compounds such as lignans and alpha-linolenic acid (ALA). Its use in the context of arteriosclerosis (the thickening and hardening of arterial walls) is supported by several scientific studies, though the evidence is moderate rather than conclusive. Research has shown that dietary fiber, especially soluble fiber, can help lower cholesterol levels, a major risk factor for arteriosclerosis. Flaxseed fiber may bind bile acids in the intestine, leading to increased cholesterol excretion and reduced serum cholesterol.

Randomized controlled trials have demonstrated that flaxseed supplementation, which includes both fiber and other components, can modestly reduce total and LDL cholesterol levels. However, it is often difficult to isolate the effect of the fiber component alone from other constituents of flaxseed. Moreover, some studies have noted improvements in blood pressure and markers of vascular inflammation, which are relevant to arteriosclerosis progression.

While there is no traditional use specifically for arteriosclerosis, the scientific literature does provide moderate evidence that flax fiber contributes to cardiovascular health, which may indirectly support its use for arteriosclerosis. Nonetheless, more large-scale, long-term studies are needed to confirm its efficacy specifically for this condition.