Table 1.

Potential beneficial and adverse effect of flavonoid supplements¹

Beneficial effects	Adverse effects
Inhibition of LDL oxidation and induction of paraoxonase	Decrease in trace element bioavailability
Activation of endothelial NO synthetase and inhibition of arginase	Antithyroid and goitrogenic activity
Inhibition of chronic inflammatory processes	Impairment of folate uptake
Inhibition of chemotactic proteins (e.g. MCP1) and cell adhesion molecules (e.g. ICAM1, VCAM1, E-selectin) expression	Inhibition of vitamin C transport
Inhibition of smooth muscle cell proliferation	Nutrient–drug interactions
Inhibition of platelet aggregation	Estrogenicity

¹MCP1, Monocyte chemotactic protein-1; E-selectin, endothelial-selectin; ICAM1, intracellular adhesion molecule-1; VCAM1, vascular cell adhesion molecule-1.