Vitamin C is a nutrient that is needed to manufacture the elastic fibers collagen and elastin, which keep the walls of the veins and arteries flexible and strong. This helps the vascular walls resist pressure and contract after dilating due to blood flow.It also keeps the valves of the veins from leaking.ertain nutrients can help to keep the arteries and veins strong and elastic for lasting overall health. Fiber is essential for balanced nutrition and normal digestive function; it also reduces the risk of other disorders such as high cholesterol, which can affect the vascular system.