Nutrition is the science that interprets the nutrients and other substances in food about the maintenance, growth, reproduction, health and disease of an organism. It includes ingestion, absorption, assimilation, biosynthesis, catabolism and excretion
A healthy diet includes; the preparation of food, and storage methods that preserve nutrients from oxidation, heat or leaching, and that reduce the risk of foodborne illness. The seven major classes of human nutrients are carbohydrates, fats, fibre, minerals, proteins, vitamins, and water. Nutrients can be grouped as either macronutrients or micronutrients.
In humans, an unhealthy diet can cause deficiency-related diseases such as blindness, anaemia, scurvy, preterm birth, stillbirth and cretinism or nutrient excess health-threatening conditions such as obesity and metabolic syndrome; and such common chronic systemic diseases such as cardiovascular disease, diabetes, and osteoporosis. Undernutrition can lead to wasting