Recent studies have also suggested that B-vitamins can improve cardiovascular health by lowering your homocysteine levels in your blood. Homocysteine is an amino acid produced by the body during the breakdown of protein. Increased levels of homocysteine in the blood can cause serious damage to your arteries, which can lead to heart disease and strokes. The levels of homocysteine are dependent on vitamins B-6 and B-12, and when deficient in these vitamins could cause your levels to rise. By taking a B-Complex daily this could lower your levels which in return can help you develop a healthier cardiovascular system.