Nutrition: (Also called nourishment or aliment) is the provision, to cells and organisms, of the materials necessary (in the form of food) to support life. Many common health problems can be prevented or alleviated with a healthy diet. The diet of an organism is what it eats, which is largely determined by the perceived palatability of foods. Dietitians are health professionals who specialize in human nutrition, meal planning, economics, and preparation. They are trained to provide safe, evidence-based dietary advice and management to individuals (in health and disease), as well as to institutions. Clinical nutritionists are health professionals who focus more specifically on the role of nutrition in chronic disease, including possible prevention or remediation by addressing nutritional deficiencies before resorting to drugs. While government regulation of the use of this professional title is less universal than for "dietician", the field is supported by many high-level academic programs. There are six basic classes of nutrients that must be considered in formulating diets; water, protein, carbohydrates, fats, vitamins and minerals. In Frank B. Morrison's Feeds & Feeding, a nutrient is defined as "Any feed constituent or group of feed constituents of the same general chemical composition that aids in support of human life." Six Classes of Nutrients 1. Water The Most Critical Nutrient! Functions in transport, chemical reactions, temperature maintenance, lubrication, etc. Water deprivation ---> dehydration ---> electrolyte imbalance ---> death Requirements vary from one species to another. Management problems leading to lack of water bad taste (high sulfur content) don’t know how to use or cannot find water 2. Carbohydrates (CHO) Functions energy source building block for other nutrients dietary excess stored as fat Two main components of carbohydrates Crude fiber (cellulose mainly) Nitrogen-free extract (soluble sugars, starches) Management Problems poor quality feedstuffs improper ration balancing 3. Fats (lipids) Functions Energy (stored at higher conc./g than CHO) Source of heat, insulation, body protection (cushioning) Essential fatty acids (immune function, anticancer link?) 4. Proteins Most expensive ingredient in ration, need decreases as animal matures Source of Essential Amino Acids (number, type and level of amino acids required varies with animal species) Functions -- basic structural unit, needed in metabolism, hormone, antibody and DNA production When fed in excess, converted to energy, fat 5. Minerals Two classes Major minerals -- Ca, P, Na, Cl, Mg, K, S Minor (Trace minerals) -- Co, Cu, F, I, Fe, Mn, Mo, Se, Zn The need for supplementation of minor minerals such as Se and F varies with the region Functions -- skeleton, protein synthesis, oxygen transport, fluid and acid-base balance in body, enzyme reactions Mineral/mineral and vitamin/mineral interactions Ca - Vitamin D P - Vitamin D Co - Vitamin B12 Se - Vitamin E Both deficiencies and excesses can lead to disease 6. Vitamins Two classes Water soluble -- B & C Fat soluble -- A, D, E, K Functions -- most vitamins have multiple functions in body involving metabolism, enzyme reactions, etc. Requirements increase with age Both deficiencies and excesses lead to disease Factors influencing the food intake: Nutritional problems may stem from physical conditions, drugs, diet, or life style factors. physical conditions: 1. Chronic illness (diabetes or neurological, cardiac, or thyroid problems) 2. Family history of diabetes or heart diseases 3. draining wounds or fistulas 4. Obesity or a weight gain of 10% above normal weight. 5. Unplanned weight loss of 10% below normal weight. 6. History of or recent GI disturbance 7. Anorexia or bulimia 8. Depression or anxiety 9. Severe trauma 10. Recent chemotherapy or radiation therapy 11. Physical limitation (paresis or paralysis) 12. Recent major surgery 13. Pregnancy, especially teen or multiple births Drugs and diet 1. Steroid, diuretic, or antacid 2. Mouth, tooth, or denture problems 3. Excessive alcohol intakes 4. Strict vegetarian diet 5. Liquid diet or nothing by mouth for more than 2 days 6. Polypharmacy Lifestyle: 1. Lack of support from family and friends 2. Financial problems 3. Isolation or homebound status The role of diet in healthy status: Nutrients play a role in maintaining health and wellness. They have several important functions 1. Providing energy which can be stored in the body or transformed for vital activities 2. Building and maintaining body tissue 3. Controlling metabolic process such as growth, cell activity, enzyme production, temperature regulation.