Yam contains considerable energy (118kcal/100g) and contains moderate amount of B group vitamins, vitamin C and minerals among which potassium is significant. Yams lack pro vitamin A.
It has been proven that yam contains a steroid that stops peroxidation of blood lipids ( the principal cause of arteriosclerosis) and lowers the level of triglycerides, which are a type of fat in the blood. All of this, together with their low fat content and their richness in potassium makes yam very appropriate for cardiovascular disorders, particularly arteriosclerosis.
NB: Arteriosclerosis (Hardening and thickening of the walls of the arteries. Arteriosclerosis can occur because of fatty deposits on the inner lining of arteries (atherosclerosis), calcification of the wall of the arteries, or thickening of the muscular wall of the arteries from chronically elevated blood pressure (hypertension)