This review article explores the role of homocysteine in the development of cardiovascular disease (CVD) and its impact on the nervous system. Homocysteine, an amino acid, is a key player in the methylation cycle and can be elevated due to genetic defects or nutritional deficiencies. Hyperhomocysteinemia, characterized by abnormally high levels of homocysteine in the blood, is associated with increased risk of CVD, including coronary artery disease, stroke, and peripheral vascular disease. The article discusses how homocysteine can trigger neuronal damage through oxidative stress, DNA damage, and activation of pro-apoptotic factors. It also highlights the central and peripheral effects of homocysteine, including its role in endothelial dysfunction, vascular stiffness, and thrombosis. The review concludes that while homocysteine is an independent risk factor for CVD, its utility as a biomarker or risk factor remains controversial due to conflicting research findings. Further research is needed to validate its role in CVD risk prediction and prevention.This review article explores the role of homocysteine in the development of cardiovascular disease (CVD) and its impact on the nervous system. Homocysteine, an amino acid, is a key player in the methylation cycle and can be elevated due to genetic defects or nutritional deficiencies. Hyperhomocysteinemia, characterized by abnormally high levels of homocysteine in the blood, is associated with increased risk of CVD, including coronary artery disease, stroke, and peripheral vascular disease. The article discusses how homocysteine can trigger neuronal damage through oxidative stress, DNA damage, and activation of pro-apoptotic factors. It also highlights the central and peripheral effects of homocysteine, including its role in endothelial dysfunction, vascular stiffness, and thrombosis. The review concludes that while homocysteine is an independent risk factor for CVD, its utility as a biomarker or risk factor remains controversial due to conflicting research findings. Further research is needed to validate its role in CVD risk prediction and prevention.