Nutrition is the science that interprets the nutrients and other
substances in food in relation to maintenance, growth, reproduction, health and disease of an organism.. In humans, an unhealthy diet can cause deficiency-related diseases such as blindness, anemia , scurvy, preterm birth, stillbirth and cretinism, or nutrient excess health-threatening conditions such as obesity and metabolic syndrome; and such common chronic systemic diseases as cardiovascular disease, diabetes,and osteoporosis. Undernutrition can lead to wasting in acute cases, and the stunting of marasmus in chronic cases of malnutrition.