n.
Processes of taking in and utilizing food substances.
Food generates energy and supplies materials used in body tissues and processes. Calorie s are supplied by carbohydrate s ( sugar s and starch es), fat s, and protein s. Other nutrients include minerals, vitamin s, and dietary fibre . Minerals are used in many ways
iron for hemoglobin ; calcium for bones, teeth, and cellular processes; sodium and potassium to regulate homeostasis , iodine to produce thyroid hormone s. Trace minerals have functions that are less well-understood. Fibre is not broken down chemically in the body but aids digestion , lowers blood cholesterol , and may help prevent some cancer s and hypertension . Different amounts of these nutrients exist in different foods; a varied diet ensures an adequate supply. Nutritional supplements, required by some people, do not compensate for an unhealthy diet. Sufficient water is always essential. Inadequate nutrient intake or absorption leads to malnutrition and disease.