Nutritional Concepts and Related Therapies

Nutritional Concepts And Related Therapies  Objectives 1. Discuss the role of the nurse in promoting good nutrition. 2. Explain the use of diet planning guides in medical nutrition therapy. 3. List the six classes of essential nutrients, and identify t...

Nutritional Concepts And Related Therapies  Objectives 1. Discuss the role of the nurse in promoting good nutrition. 2. Explain the use of diet planning guides in medical nutrition therapy. 3. List the six classes of essential nutrients, and identify those that provide energy. 4. List the functions and food sources of protein, carbohydrates, and fats.  Objectives 5. List food sources and possible health benefits of dietary fiber. 6. Distinguish between saturated, unsaturated, and trans fats and cholesterol; identify current recommendations for dietary intake of fats and cholesterol. 7. Discuss key vitamins and minerals, their role in health, and their food sources.  Objectives 8. Discuss changes in nutrient needs throughout the life cycle, and suggest ideas to ensure adequate nutrition during each stage of life. 9. Identify the effects of common medications on nutritional status. 10. Identify standard hospital diets and modifications for texture, consistency, and meal frequency.  Objectives 11. List medical and surgical conditions that require a high kilocalorie and high protein diet, and suggest ways to increase kilocalories and protein in the diet. 12. Define obesity, and list components of an effective weight management program. 13. Distinguish among anorexia nervosa, bulimia nervosa, and binge-eating disorder. 14. Describe dietary management of type 1 and type 2 diabetes mellitus.  Objectives 15. Describe fat modified diets and list conditions requiring a fat modified diet. 16. Identify medical and surgical conditions necessitating modifications in sodium, potassium, protein, or fluid intake, and describe the dietary adjustments necessary in these conditions. 17. Define enteral nutrition and parenteral nutrition, and list medical and surgical conditions in which nutritional support is often indicated.  Nutrition Nutrition is the sum of all processes involved in taking in nutrients and using them to maintain body tissue and provide energy. It is one of the foundations for life. Eating the right kinds and amounts of food and following good dietary habits throughout the entire life means a healthier body and mind, greater vitality and energy, and greater resistance to disease. For nurses, it is important to always consider the patient's nutritional state and to assess the patient's nutritional history in order to plan quality patient care. Role of the Nurse in Promoting Nutrition Patients look to the nurse as a source of health information. The licensed practical nurse (LPN/LVN) may be responsible for assisting a patient to eat, for recording a patient's intake, for observing a patient for signs of poor nutrition, and for communicating any dietary concerns to the health care provider, dietitian, or other members of the health care team.  Basic Nutrition Diet Planning Guides Standards are guidelines describing how good dietary habits can promote health and reduce the risk for major chronic diseases. Over the years, these nutritional guidelines have changed in accordance with the growing knowledge of how nutrition affects health. The guidelines started as a farmers' bulletin more than 100 years ago and then evolved to the Basic 7, the Basic Four, the Food Guide Pyramid, MyPyramid, and currently MyPlate.  MyPlate MyPlate was developed in the United States by the U.S. Department of Agriculture (USDA) and was introduced in 2011. MyPlate is an image of a round plate divided into four different- colored sections. The colored areas show people how much they should eat from three of the four food groups: vegetables and fruits, grains and proteins. A smaller circle next to the plate represents the fourth food group, dairy. Along with the image, the USDA suggests that people balance calories by reducing portions; increase intake of fruits, vegetables, and whole grains; and reduce the amount of sodium and sugary foods in the diet.  Dietary Guidelines for Americans Over the years, the U.S. Department of Health and Human Services and the USDA have developed dietary guidelines for the U.S. population. The Dietary Guidelines for Americans (U.S. Department of Agriculture & U.S. Department of Health and Human Services, 2010) is the latest of these guidelines and include recommendations for the general population, as well as for specific population groups such as pregnant and lactating women. The recommendations are intended to help people choose an overall healthy diet. These guidelines emphasize balancing calories with activity to manage weight; consuming more fruits, vegetables, and whole grains; increasing fat-free or low-fat dairy products and seafood; and consuming less sodium, saturated fat, trans fat, cholesterol, added sugars, and refined grains.  The Dietary Guidelines for Americans (USDA & U.S. Department of Health and Human Services, 2010) is used to form the U.S. federal nutrition policy and directly affects federal nutrition programs such as food stamps, school breakfast and lunch programs, and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)..  Dietary Reference Intakes Dietary reference intake (DRI) refers to a set of nutrient-based values that serve for both assessing and planning diets. The DRIs replace and expand on the recommended dietary allowances (RDAs). The DRIs are a combination of the RDAs, adequate intake, tolerable upper intake level, and the estimated average requirement of each nutrient. The purpose of DRIs is to help individuals optimize their health, prevent disease, and avoid consuming too much of a nutrient.  Essential Nutrients Basic Functions A nutrient is a chemical compound or element found in food that is necessary for good health. Essential nutrients are nutrients that the body cannot make in the amounts essential for good health; therefore, it is necessary to obtain these nutrients through the diet or from other sources. There are six classes of essential nutrients: carbohydrates, fats, proteins, vitamins, minerals and water.  Each is necessary for life. Three major functions of nutrients include: (1) providing energy (2) building and repairing tissue (3) regulating body processes.  Providing energy A kilocalorie (kcal) is a measurement of energy, much as a pound is a measurement of weight. The more kilocalories a food has, the more energy it will provide. Of the six essential nutrients, three provide energy: carbohydrates, fats and proteins. Vitamins, minerals and water do not provide energy but are nonetheless essential nutrients.  Building and Repairing Tissue Many nutrients are necessary for building and repairing tissue, but the nutrient that plays the biggest role is protein. Calcium and phosphorus, both minerals, are necessary nutrients in bone structure, and Iron, another mineral, makes up a large part of the hemoglobin in red blood cells. Fat also plays a role in building and repairing tissues; it is found in all cell walls.  Regulating body processes Metabolism is the combination of all chemical processes that take place in living organisms. It is a continuous process of building up and breaking down tissues. Nutrients play various roles in metabolism and thereby help regulate certain body processes. Water is an integral part of almost all chemical reactions in the body.  Carbohydrates Carbohydrates (CHO) are organic compounds containing carbon, hydrogen and oxygen. The main function of carbohydrates is to provide energy. Carbohydrates are classified as either simple or complex according to the number of sugar units they contain.  Simple carbohydrates Carbohydrates are made of molecular units called saccharides, or sugar units. The simple carbohydrates (often called simple sugars) include the monosaccharides and the disaccharides. Monosaccharides have only one sugar unit. They require no digestion and are absorbed directly into the blood.  Another important monosaccharide is glucose. Glucose is often called “blood glucose” because it is the major form of saccharides, or sugar, in the blood.  Simple carbohydrates Disaccharides are made up of two sugar units bonded together. Once taken into the body, disaccharides are reduced by hydrolysis into monosaccharides before being absorbed. Simple sugars are found naturally in many nutritious foods such as milk and fruit and should not be excluded from the diet.  Complex carbohydrates Complex carbohydrates are termed polysaccharides because they are made of long chains of glucose (sugar) units. The three types of complex carbohydrates, or polysaccharides, include starch, glycogen and dietary fiber.  All carbohydrates, including complex carbohydrates, break down into simple sugars when they are digested. But because starch is a larger, more complex molecule, it breaks down more slowly and provides energy over a longer period of time.  Glycogen, also called animal starch, is the stored form of carbohydrates. It is made from simple sugars and stored mainly in the liver and in muscles. It is used when the body's blood glucose level is low. Dietary fiber refers to foods that humans cannot break down (digest). It is found mostly in plants and, like polysaccharides, is made of long chains of glucose units. Most of the fiber consumed is eventually excreted in the feces and has no nutritive value. It can lower cholesterol and blood glucose levels and assist in weight loss. Dietary fiber is classified on the basis of its ability to dissolve in water. Both types of fiber, soluble and insoluble provide a variety of health benefits. Insoluble fiber is found in wheat bran, vegetables, whole grains, and some fibrous fruits. Insoluble fiber softens stools, speeds transit of foods through the digestive tract, and reduces pressure in the colon.  Water-soluble fiber is found in fruits, oats, barley, and legumes. It binds with bile acids and cholesterol in the digestive tract to prevent their absorption. This helps lower cholesterol levels and reduces the risk of cardiovascular disease.  Soluble fiber attracts water and turns to gel during digestion, thus slowing digestion. This provides a feeling of fullness and may aid in weight loss.  Daily requirements. While eating enough fiber is important in a healthy diet, there may be hazards to consuming too much fiber. Sudden increases in fiber can cause bloating, gas, and constipation. Too much fiber can interfere with mineral absorption, which can lead to problems such as osteoporosis and anemia. It is suggested that adequate fiber be obtained by eating appropriate amounts of fruits and vegetables rather than adding fiber supplements. Digestion and metabolism of carbohydrates Digestion of carbohydrates begins in the mouth with mechanical digestion. Chewing breaks up the food (carbohydrates) into small pieces so that it can be swallowed. In the stomach, mechanical digestion continues so that the pieces are broken down into even smaller parts and combined with gastric secretions Once the pieces are in the small intestine, chemical digestion begins in full force. Enzymes from both the intestinal wall and the pancreas aid in digesting the carbohydrates.  All carbohydrates except fiber are broken down in the digestive tract into monosaccharides (single- sugar units) before they are absorbed and eventually converted to glucose. Glucose circulates in the bloodstream and is used by the cells for energy. When the body's energy needs are met, the extra carbohydrates are converted to glycogen, which is stored in the liver and muscles until it is needed. Once glycogen stores in the liver and muscles are full, the body converts the remaining carbohydrates to fat and stores them as adipose tissue.  Fats (Lipids) Lipids are organic substances of a fatty nature that are insoluble in water and necessary for good health. Both fats and cholesterol are lipids. Lipids perform a number of functions in the body.  As adipose tissue, fat helps insulate the body from temperature extremes and serves as a cushion to protect organs and other tissues from being bumped or jarred. Dietary fat provides satiety, a feeling of fullness and satisfaction from food. It adds flavor and aroma to foods and provides the body with the essential fatty acids. Like carbohydrates, lipids are composed of carbon, hydrogen, and oxygen. Unlike carbohydrates, lipids also contain fatty acids and glycerol. Because of this, lipids may also be called glycerides or, more specifically, triglycerides. Fatty acids, the building blocks of fat, are classified as either saturated or unsaturated. All fats and oils contain a combination of saturated and unsaturated fatty acids in various proportions.  Saturated fatty acids A saturated fatty acid is one whose chemical bonds are completely filled, or saturated, with hydrogen. Saturated fats are generally of animal origin and are solid at room temperature. Saturated fats, although an important part of a healthy diet, tend to increase blood cholesterol levels, thus increasing the risk for atherosclerosis (the buildup of fatty deposits on the artery walls) and heart disease.  Unsaturated fatty acids An unsaturated fatty acid has one or more places on its chemical chain in which hydrogen is missing. Most unsaturated fats are from plant sources and are liquid at room temperature. Unsaturated fats, especially monounsaturated fats, are thought to lower low-density lipoprotein cholesterol, especially when combined with lower intake of saturated fat and trans fat.  Hydrogenated fats. Hydrogenation is a process in which hydrogen is added to a fat of vegetable origin (unsaturated) in order to make it more saturated or solid. This then makes the oil more stable and less susceptible to becoming rancid. When only some of the hydrogen has been replaced, the oil is considered partially hydrogenated. Most vegetable spreads, such as corn oil margarine, have been hydrogenated to some extent.  Trans fatty acids Trans fatty acids are unsaturated fatty acids that have been completely hydrogenated. Synthetic trans fatty acids are produced during hydrogenation and can be found in some deep- fried restaurant foods; packaged cookies, crackers, and other baked goods; some margarines; and shortening.  Trans fatty acids in the diet are similar to saturated fats and tend to increase blood cholesterol levels. Therefore, they should also be used sparingly in a healthy diet.  Cholesterol Cholesterol is a lipid belonging to a class of chemical substances called sterols. Cholesterol is a building block for cell membranes and for hormones, such as estrogen and testosterone. It is synthesized in the liver and is found in foods of animal origin.  Plant foods and oils do not contain cholesterol. In fact, plant sterols sometimes decrease cholesterol levels in the blood. The amounts of dietary cholesterol (the cholesterol found in foods) are highest in organ meats and egg yolks.  Dietary cholesterol is also present in smaller but significant amounts in seafood, meats, poultry, and dairy products. The recommended intake of dietary cholesterol is an average of no more than 300 mg/day.  Digestion and metabolism of fat In order for fat to be digested, it has to be emulsified, or broken into smaller globules. Bile, a secretion of the liver, is necessary to emulsify fat. Bile is stored in the gallbladder and dispensed into the duodenum when fat is present. Once fats are emulsified, the body is able to break down and absorb them.  The human body makes four types of lipoproteins; chylomicrons, high-density lipoproteins (HDLs), low- density lipoproteins (LDLs), and very low–density lipoproteins (VLDLs). LDLs and HDLs are important in the study of cardiovascular disease. Both of these lipoproteins carry cholesterol in the bloodstream. It appears that the cholesterol found in LDLs increases the risk of atherosclerosis by contributing to plaque buildup on the artery walls. In contrast, HDLs seem to have the opposite effect. HDLs transport cholesterol from the bloodstream to the liver to be degraded and excreted. LDLs are sometimes referred to as carrying “bad” cholesterol, whereas HDLs are referred to as carrying “good” cholesterol.  Protein Protein is another nutrient vital to the human body. Proteins provide the building blocks for blood and bone, and they are a structural part of every cell. The human body contains thousands of different proteins, all of which are essential for tissue growth, repair and wound healing.  Enzymes are proteins produced by living cells. They cause chemical reactions within the body without being changed in the process. They are necessary for digestion and metabolism. Carbohydrates, fat and protein all contain carbon, hydrogen and oxygen, but protein is unique in that it also contains nitrogen. All of these elements—carbon, hydrogen, oxygen, and nitrogen—combine in specific ways to form amino acids. Amino acids are the building blocks of protein. Approximately 20 amino acids have been identified as important to the body's metabolism, but only 9 of them are considered essential amino acids; that is, since the body does not make them in sufficient quantity to sustain health, it is necessary to obtain them from the diet.  Complete proteins A complete protein is one that contains all nine essential amino acids in sufficient quantity and ratio for the body's needs. Complete proteins are generally of animal origin and are found in foods such as meat, poultry, fish, milk, cheese, eggs and soy products.  Incomplete proteins Incomplete proteins are those that are lacking in one or more of the essential amino acids. Incomplete proteins are of plant origin. This includes the protein in grains, legumes, nuts and seeds.  Vegetarian diets For vegetarians and other people who choose to limit their intake of animal foods, obtaining sufficient amounts of protein may be challenging. Depending on the beliefs of the person following a vegetarian diet, the diet may vary, and the amount of protein may or may not be adequate to meet the body's needs. A vegetarian diet is made up of mainly plant foods. Some vegetarian diets include dairy products or eggs, or both, as well. The strictest vegetarian diet, the vegan diet, excludes all animal products, and more planning is required in order to obtain sufficient protein.  To offset this deficit, vegans eat soybeans, soy milk, and other soy products to enhance protein intake. Strict vegetarians also need to include a reliable source of vitamin B12 in the diet, since vitamin B12 is found exclusively in animal foods.  Digestion and metabolism of protein Protein-containing foods are the body's only external source of nitrogen. Once a protein-containing food is eaten, the nitrogen is removed from the amino acid and some of it is excreted as urea nitrogen in the urine. The nitrogen that is not excreted is then used to make other amino acids.  Nitrogen balance, or nitrogen equilibrium, is achieved when the amount of nitrogen (protein) taken in is equal to the amount of nitrogen excreted in the urine.  Positive nitrogen balance A positive nitrogen balance exists when more nitrogen is taken in than is excreted. In this situation, the body is building more tissue (anabolism) than it is breaking down. This is seen during periods of growth such as infancy, childhood, adolescence and pregnancy.  Negative nitrogen balance A negative nitrogen balance exists when less nitrogen is being consumed than is being excreted. This condition occurs when insufficient protein is being taken in and the body is breaking down more tissue (catabolism) than it is building. Nitrogen balance is negative in states of undernutrition, illness and trauma.  Skipping protein food for one day is not likely to create a negative nitrogen balance so noticeable physical signs are not likely to occur. In contrast, prolonged negative nitrogen balance can eventually cause atrophy of muscles, as well as poor functioning of all body systems.  Protein energy malnutrition When there is a lack of energy or protein intake, Protein Energy malnutrition (PEM) may result. PEM is fairly common in both children and adults in developing countries, and malnutrition is associated with more than half the deaths of children younger than 5 years worldwide. Two types of PEM exist: marasmus and kwashiorkor. Marasmus is a protein deficiency that affects people of all ages. It is a chronic condition characterized by wasting of body tissues. As the disease progresses, subcutaneous fat stores and then muscle stores are depleted, leaving the victim with a “skin and bones” appearance.  Kwashiorkor occurs as a result of severe protein restriction in the presence of other calories. It occurs most often in children in developing countries, with onset at approximately the time the child is weaned from breastfeeding. Kwashiorkor is characterized by edema in the feet, legs and often in the face and hands. There may also be swelling in the abdomen. Protein Energy malnutrition (PEM) is usually accompanied by multiple nutrient deficiencies and can lead to stunted growth and impaired cognitive development in children, reduced mental and physical capacity, and lowered resistance to infections. Vitamins Vitamins are organic compounds that are essential in small quantities for normal metabolism and for growth and maintenance of the body. Vitamins themselves are not sources of energy; they work in conjunction with other nutrients in the body to regulate many processes, including energy production. Because the amount of vitamins needed by the body is so small, they are sometimes referred to as micronutrients. Many compounds, including vitamins, are susceptible to destruction by heat, light, and exposure to air.  Vitamins are classified by whether they are soluble in fat or soluble in water. Vitamins A, D, E, and K are fat soluble. Fat-soluble vitamins are absorbed from the intestine in the same way as fats, and, like fats, they can be stored in the body. Because of this storage capacity, excessive intake of fat-soluble vitamins, especially A and D, can lead to toxicity and death. The water-soluble vitamins are those that dissolve in water and include the B vitamins and vitamin C.  The body is not readily able to store these vitamins since they are water soluble, and excesses are generally excreted in the urine. Antioxidant vitamins These vitamins, E, C and A (in the pre-vitamin form, have been found to delay or prevent the destruction or breakdown of cell membranes in the presence of oxygen (antioxidants) and thereby reduce the risk of developing certain cancers, inflammatory diseases, Alzheimer's disease and heart disease. Vitamin C Vitamin C, or ascorbic acid, has many functions in the body. It contributes to the healing of wounds, burns and fractures; it serves as an antioxidant; and it is necessary for adrenal gland function.  Although it is true that adequate vitamin C is necessary for proper immune function, large supplemental doses of the vitamin have not been consistently and conclusively shown to be of greater value than what can be obtained solely through diet.  Vitamin C (ascorbic acid) DEFICIENCY SIGNS AND SYMPTOMS Scurvy: gingivitis, bleeding gums, easy bruising, increased infections, poor wound healing, rough skin, joint pain, muscle atrophy, fatigue  B-Complex vitamins There are several different B vitamins. All are water soluble, and all are necessary for proper metabolism. Of all the B-complex vitamins, three are especially important.  Niacin Niacin (vitamin B3) is important in the production of energy from glucose and is involved in the repair of DNA. This requirement is easily obtained by eating meat, poultry, fish, peanuts or enriched whole grain breads and cereals. Niacin deficiency is rare, and there is usually no risk for toxicity except with excess vitamin supplementation.  Folate (folic acid) Folate is a water soluble B vitamin that is the natural form found in foods such as spinach, lentils and garbanzo beans. Folic acid (vitamin B9) is necessary for the formation of DNA and proper cell division. A deficiency can lead to megaloblastic anemia.  Megaloblastic anemia is an anemia (of macrocytic classification) that results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis (M) stage. This leads to continuing cell growth without division, which presents as macrocytosis.  Vitamin B12 Vitamin B12 plays an essential part in the production of hemoglobin and myelin. In order to absorb vitamin B12, a protein secreted by the stomach is required. This protein is called intrinsic factor and is produced in the lower portion of the stomach. When the intrinsic factor is missing—for example, after stomach excision or resection—vitamin B12 cannot be absorbed, and pernicious anemia (a progressive macrocytic megaloblastic anemia) develops.  Treatment of pernicious anemia consists of vitamin B12 injections for a lifetime. B12 is found primarily in foods of animal origin, people who follow a strict vegetarian diet (vegans) do not always receive adequate vitamin B12 from food. Vitamin B12 can easily be obtained from eating animal products such as lean meat, liver, seafood, eggs and dairy products.  Vitamin A Vitamin A, an antioxidant and a fat-soluble vitamin, is available in two forms: retinol (preformed) and carotene (provitamin). Both forms of vitamin A are important for maintaining vision, as well as for skin and bone growth. Most people consume vitamin A in the form of beta- carotene, found in bright yellow and orange fruits, carrots, pumpkin, and dark green leafy vegetables. Vitamin D Vitamin D promotes the absorption of calcium and phosphorus, which in turn promote bone and tooth health. It can be found in most fortified dairy products, in yeast, and in fish liver oils. The body also synthesizes vitamin D when the skin is exposed to sunlight. Vitamin D deficiency can lead to brittle bones (osteoporosis) and may be of concern for some older adult patients in long-term care facilities.  Vitamin K Vitamin K plays a role in blood clotting. Because of the effect that vitamin K has on clotting, patients who are taking antiplatelet drugs or anticoagulants should consume consistent amounts of vitamin K from day to day.  Large fluctuations in vitamin K intake have the potential to alter the effects of the anticoagulant drug.  Minerals Minerals differ from vitamins in that they are inorganic and they are single elements rather than compounds. Minerals are similar to vitamins in that they help regulate bodily functions without providing energy and are essential to good health. Minerals are classified as either major minerals or trace minerals. Major minerals include calcium, phosphorus, magnesium, sulfur, sodium, potassium and chloride. The trace minerals include iron, zinc, iodine, selenium, copper, manganese, fluoride.  Calcium Calcium has several functions in the body. It is important in the formation of bones and teeth; it plays a role in blood clotting; and it plays a role in the transmission of nerve impulses and muscle action. Calcium is necessary to protect against osteoporosis. Osteoporosis is an abnormal reduction in bone density that leads to bone pain, fractures, loss of stature and deformities such as Kyphosis (hunched back). Women are affected more than men. Many hip fractures are the result of osteoporosis. Diets high in sodium and protein and low in potassium appear to contribute to osteoporosis by increasing the amount of calcium that is excreted in the urine.  Sodium In the body, sodium functions as an electrolyte (a compound that is able to conduct an electrical current). Sodium is needed in very small amounts for good health and is found naturally in almost all foods.  Salt (sodium chloride) is the largest contributor of sodium in the diet and, if eaten in large quantities, can cause hypertension and edema.  Because sodium may be lost with heavy sweating, diarrhea, vomiting, renal disease and cystic fibrosis, it is important to monitor sodium levels in individuals presenting with any of these symptoms or diseases.  Potassium Potassium, also an electrolyte, is needed for conduction of nerve impulses and the contraction of muscles, including the heart muscle. It helps maintain acid-base balance and is required for conversion of glucose to glycogen. It also plays a role in energy production and insulin release from the pancreas.  A severe deficiency of potassium can lead to hypokalemia (blood potassium level less than 3.5 mEq/L), which is a life-threatening state. Individuals taking potassium-wasting diuretics and chronic laxative users may also be at risk for developing hypokalemia.  Excessive intake of potassium is also a problem and can lead to hyperkalemia (blood potassium levels above 5.0 mEq/L). This can result in renal failure, adrenal failure, and cardiac arrest. Potassium deficiency (in the absence of hypokalemia) may lead to increased blood pressure, increased risk of kidney stones, and increased bone loss. Potassium is found naturally in many foods, especially fruits, vegetables, and milk. Potassium supplementation is not recommended, except when prescribed by a health care provider, because the risk of toxicity and cardiac arrest is high.  Iron Iron is an essential part of hemoglobin and myoglobin, as well as a number of enzymes throughout the body. Hemoglobin is part of the red blood cell and carries oxygen to the cells. Myoglobin is similar to hemoglobin but is found in the muscle tissue and is responsible for storing oxygen in the muscle.  A lack of iron in the body can cause iron-deficiency anemia. Iron-deficiency anemia seems to be the most prevalent nutritional problem in the world, and it may result not only from inadequate iron in the diet but also excessive blood loss, absorption problems, and hemoglobin production problems.  A deficiency of iron limits oxygen delivery to the cells, which results in fatigue, weakness, headaches, pallor of skin and mucous membranes, poor work performance, and decreased immune function.  In children, iron deficiency has been associated with a short attention span, irritability and a reduced ability to learn. Children aged 6 months to 4 years, adolescents, menstruating women, and pregnant women are at greatest risk for iron-deficiency anemia. Koilonychia also known as spoon nails, is a nail disease that can be a sign of hypochromic anemia, especially iron-deficiency anemia. " It refers to abnormally thin nails (usually of the hand) which have lost their convexity, becoming flat or even concave in shape.  Vitamin and mineral supplementation Americans tend to be very interested in vitamins and minerals. There have been claims that these nutrients help reduce stress, prevent colds, increase sexuality, increase energy, improve physical performance and reduce the risk for certain diseases. Many people believe that if some is good, more is better.  It is best to avoid large doses, or megadoses, of nutrients and to avoid taking numerous types of supplements, except for therapeutic purposes. All medications, including vitamins and minerals, should be taken under the supervision of a health care provider.  Water Water is the nutrient most vital to life; humans can survive longer without food than they can without water. Lack of this nutrient brings about detrimental changes in the body more rapidly than lack of any other. Water makes up approximately 60% of adult body weight and 80% of infant weight and performs many functions in the body. It provides form and structure to body tissues, acts as a solvent, and is necessary for most of the body's chemical processes.  Water transports nutrients and other substances throughout the body by way of the blood, body secretions and tissue fluids. It lubricates and protects moving parts of the body, such as joints; it aids in digestion; and it is necessary for regulating body temperature.  Severe dehydration (more than 10% of body weight lost) could become a life-threatening situation. Signs of dehydration include poor skin turgor; flushed, dry skin; dry mouth; cracked, dry lips; decreased urine output; irritability; and disorientation.  Life Cycle Nutrition Pregnancy and Lactation Nutrient needs are greater during periods of intensive growth, such as pregnancy and infancy, than at any other time during the life cycle. Optimal nutrition during pregnancy reduces the risk of complications, premature deliveries and low birth weight. Even the mother's nutrition before conception plays a role in the final outcome of a pregnancy. Adequate folic acid is thought to greatly reduce the risk of neural tube defects, such as spina bifida, in the infant.  Concerns in Pregnancy Weight gain Weight gain in pregnancy is important. Optimal weight gain for the average woman is 25 to 35 pounds. Underweight women should gain between 28 and 40 pounds, whereas overweight women should gain only between 15 and 25 pounds.  Encourage pregnant young adolescents to strive for higher weight gain in order to maintain their health, as well as that of the fetus. Intentional weight loss should not be attempted during pregnancy.  Mothers who do not gain adequate weight during pregnancy risk giving birth to a low-birth-weight (LBW) infant (weighing less than 5.5 pounds). These babies are at greater risk for complications during and after birth.  Discomforts and complications Many women experience discomforts during pregnancy. Common among these are nausea and vomiting, often referred to as “morning sickness.” Occasionally, pregnancy brings about medical conditions that pose potential dangers for both the mother and the fetus. Hypertensive disorders of pregnancy include chronic hypertension, preeclampsia, eclampsia and gestational hypertension. Proper nutrition is vital both before and throughout pregnancy and may help in the management of blood pressure during pregnancy.  Controlling blood glucose levels during pregnancy is very difficult. Hypoglycemia is common in the first trimester because of low glucose levels, increased insulin production, and nausea and vomiting. During the latter two trimesters, insulin resistance is common, and so the woman may be more likely to experience hyperglycemia. Gestational diabetes is often controlled through nutrition therapy and moderate exercise, but for women who are unable to achieve glycemic control, insulin therapy is often necessary. Anemia is another common nutritional problem in pregnancy; both iron-deficiency anemia and folic acid–deficiency anemia are possible.  Nutritional Suggestions to Relieve Some Discomforts of Pregnancy Nausea, Vomiting, Gastric Distress To reduce nausea, eat soda crackers or other dry grain products before getting out of bed. Consume five or six small meals that include protein each day. Avoid letting the stomach become empty. Drink plenty of fluids during the day; however, drink liquids before or after meals to avoid feeling too full. Avoid high-fat or fried foods in excess.  Limit consumption of foods with strong odors during times of nausea. Avoid odors that bother the patient. Allow time after eating before lying down or going to bed to prevent epigastric distress. Constipation Drink plenty of fluids, especially water. Include fiber-rich foods at each meal. Include moderate daily exercise.  Nutrient Needs During Pregnancy and NONPREGNANT PREGNANCY Lactation LACTATION REASONS FOR FOOD SOURCES ADULT INCREASED NUTRIENT NEED DURING PREGNANCY Protein Rapid fetal Milk, cheese, tissue growth eggs, meat, 46-50 g 60 g 60 g grains, Amniotic fluid legumes, nuts, soy Placental products growth and development Maternal tissue growth: uterus, breasts NONPREGNANT ADULT PREGNANCY LACTATION REASONS FOR INCREASED NUTRIENT NEED DURING PREGNANCY Calories * Increased basal metabolic rate, 2200 2500 2700 energy needs  Practices to avoid During pregnancy, there are several things a woman should avoid in her diet. Alcohol, caffeine and nicotine are three of the more important substances to avoid. Alcohol contributes to an increased risk for mental and physical disabilities in the fetus.  Fetal alcohol syndrome is characterized by physical deformities, learning disabilities and behavioral problems. High caffeine consumption may be a problem and is associated with delayed conception, increased risk of spontaneous abortion and low birth weight.  Pregnant should not consume more than 200 mg of caffeine per day (one 12-ounce cup). Nicotine in tobacco smoke is another substance that should be avoided during pregnancy. Studies have shown that smoking decreases blood supply to the fetus. Taking drugs of any kind during pregnancy should be avoided unless done under the direct supervision of a health care provider. Advise women to avoid all drugs, including over-the-counter medications and herbal or botanical supplements, until they have consulted their health care provider.  Lactation During lactation, a woman should follow a diet similar to that followed during pregnancy. Kilocalorie needs and many nutrient needs are actually higher than during pregnancy. Lactating women should increase their caloric intake by 500 kcal/day more than their prepregnancy intake.  Infancy The time from birth to 1 year of age is one of rapid growth and development. The infant's birth weight doubles by 6 months and triples by 1 year of age. Nutrition plays an important part in this rapid growth.  Breast milk or iron-fortified infant formula is recommended for the entire first year of life. Breast milk contains antibodies and easily digested fats. Regular cow's milk (whole, low-fat, or skim) should be avoided during the first year of life.  Introduction of regular cow's milk before 1 year of age could lead to iron-deficiency anemia and increase the risk for developing milk allergies later in life. Also, the fat in cow's milk is more difficult for the infant to digest and could create GI disturbances. Acceptable alternatives to cow's milk during the first year of life are breast milk and iron-fortified infant formula. Whole milk is acceptable after the first year, but skim and low-fat milk are inappropriate until the child is 2 years of age because the fat content is insufficient. In the first 6 months, water, juice and other solid foods are generally unnecessary for infants. In most cases, breast milk or formula provides adequate nutrition for about the first 4 to 6 months.  At approximately 4 to 6 months of age, depending on the infant's development, it is possible to introduce solid foods into the diet. Solid feedings are usually initiated with iron-fortified rice cereal because rice cereal is less allergenic than most other foods. This allows sufficient time to detect any food-related allergies. Infants younger than 12 months of age should also never be given honey, especially wild honey, because of the potential for botulism. It is important to remind parents that once the baby develops teeth, the nighttime feeding should be limited to water, and breastfeeding mothers should not allow the infant to nurse continuously throughout the night. Prolonged exposure of the teeth to formula or breast milk is a major contributing factor to dental caries.  Childhood At approximately 1 year of age, appetite generally tapers off, and the growth rate slows. Most children prefer simple, plain foods and will eat what they need if they are not coaxed, nagged, bribed, rewarded, or influenced by television commercials. Childhood is a critical time for instilling good dietary habits. Caregivers must carefully supervise children's eating habits and offer nutritious meals and snacks. But they must also allow the child the freedom to decide what and how much to eat.  Adolescence Puberty is another time in the child's life when growth is very rapid and nutrition becomes more important for proper development. Adolescents may be more likely to practice good nutrition if they consider factors such as how nutrition helps skin (facial appearance), strength (for any athlete), and the ability to concentrate in school.  Because of the accelerated growth rate and participation in sports, adolescents may need more food to supply their energy requirements. Food choices are sometimes not wise ones and tend to be influenced by peer preference. Their diets are often filled with kilocalorie-rich and nutrient-poor snack foods. Common dietary inadequacies in adolescence include iron and calcium deficiencies (particularly in girls) and deficiencies in vitamins A and C and folic acid. When good nutritional habits have been established earlier in life, adolescent nutrition is likely to be better balanced than in cases in which nutritional teaching has been insufficient.  Another nutritional factor to consider is that during adolescence, many teenagers experiment with alcohol and drugs, and these substances may have detrimental effects on their nutritional status as well. Obesity in young people is a common problem.  Diets sometimes cause harm by suppressing development and can even leading to eating disorders. Encourage adolescents to develop healthy eating habits and to use moderation. Emphasize adequate physical activity, and suggest limiting television viewing and computer usage.  Adulthood During adulthood, nutrient needs change little in comparison with those of the adolescent. The combined effects of decreased energy needs and reduced physical activity often result in weight gain.  Aging is associated with increased health concerns. Older adults suffer from conditions such as heart disease, arthritis, osteoporosis, diabetes, kidney disease, and other disorders with increased frequency. Special conditions may warrant differing nutrient needs that may vary greatly from individual to individual. Aging is associated with increased health concerns. Special conditions may warrant differing nutrient needs that may vary greatly from individual to individual. Nutritional Concerns of Adults in Long-Term Care Facilities Malnutrition is a common problem among residents in long-term care facilities and profoundly influences physical health and quality of life.  Residents of long-term care facilities may experience cognitive or physical impairment, disease processes, and emotional disturbances, all of which have an effect on nutritional intake and status. Many residents in the long-term care environment need some assistance or encouragement with eating and drinking. Restricted diets may be prescribed for residents of long-term care facilities. Inadequate fluid intake and dehydration are sometimes secondary to decreased thirst sensation, decreased independence, dysphagia (difficulty swallowing), and incontinence. Pressure sores may occur in nonambulatory residents, increasing kilocalorie, protein, and nutrient needs.  All members of the health care team must work together to coordinate care to ensure that the nutritional needs of the facility residents are met. Offering familiar foods and incorporating cultural needs within the prescribed diet is important. Fluids should be offered to residents at all meals and between meals to ensure adequate intake.  Health Promotion: Ways to Encourage Good Dietary Habits in Children Encourage children to eat meals and snacks at regular times and at the table. By having set eating times, children will learn that they cannot eat continually all day. Try to make meals relaxed and enjoyable. Children need time to eat, and mealtimes should be a positive experience.  Offer a variety of foods from all food groups, and allow children a choice of food, within reason. Do not force children to eat more than they want to eat. Give small servings, or teach children how to serve themselves small servings. Then let them have seconds if they are still hungry. Offer new foods, but do not force children to eat foods they dislike. If the child will not eat a new food, quietly remove the food and offer it again at another time. Encourage children to help with food selection and preparation. Keep nutritious snacks available, such as fruits, cheese, crackers, raw vegetables, and bread. Most children need to snack.  Limit sweets, and do not use sweets and foods as rewards or bribes. As adults, set a good example by practicing sound dietary and exercise habits.  Life Span Considerations: Older Adults Aging and Nutrition Aging often affects the eating process. Changes in dentition, decreased saliva production and alterations in swallowing all have the potential to affect nutrient intake. The aroma and taste of foods are sometimes affected by normal changes of aging. The use of flavorings, seasonings and spices to enhance flavor and aroma is often helpful. Older adults experience changes in digestive secretions, GI mucosa and enzyme production. Older adults may have a greater need for certain nutrients, including protein, riboflavin, vitamin B6, folic acid, vitamin B12, vitamin D, and calcium. A multivitamin and mineral supplement supplying 100% of the RDA is often beneficial for individuals.  Many older adults take numerous medications. Many medications tend to affect nutritional status. Be aware of drug-nutrient interactions and side effects that have the potential to influence dietary intake.  Because of illness, restricted mobility, or financial limitations, or a combination of these, some older adults have difficulty obtaining and preparing nutritious food.  Age-related social and mental changes such as forgetfulness, loneliness and apathy are likely to affect the eating habits of older adults.  Chronic medical conditions often necessitate the use of therapeutic diets. The most common such conditions in older adults include diabetes mellitus, cardiovascular disease, renal insufficiency, osteoporosis, diverticulosis, anemia, and lactose intolerance.  Nutrient-Drug Interactions Many older adults take a number of prescription medications daily to manage medical conditions or disease states. Medications have the potential to either increase or decrease appetite or the ability to eat.  In many instances, they also affect the absorption, metabolism and excretion of some nutrients. Conversely, food intake and vitamin or mineral supplementation may affect the absorption, distribution, metabolism and action of some medications  Caffeine Caffeine is a central nervous system stimulant and a diuretic. It has potential to cause nervousness, irritability, anxiety, insomnia and heart dysrhythmias and palpitations. It also tends to affect blood pressure, circulation and gastric acid secretion.  Reducing caffeine intake can often alleviate the symptoms of an anxiety attack and possibly prevent the need for another drug to relieve anxiety. Any Questions?