A&AE 350 - Exam #1 study guide answers

Who is most likely to be iodine deficient?

People living in regions with iodine-deficient salts, people with marginal iodine status who eat foods containing goitrogens (inhibit uptake of iodine), people who do not use iodized salt and pregnant women

What is a major issue with early pregnancy in undernourished girls?

Undernourished girls grow for a longer period of time, so may not be finished growing before the pregnancy. This leads to smaller infants due to competition for nutrients and poorer placental function. Calcium is a special concern since bones of adolescents have not reached maximum density. Higher maternal and infant mortality and preterm delivery with pregnancies

What are the symptoms of iron deficiency?

Fatigue, dizziness/light-headedness, brittle nails, fast HR, pallor, or SOB

Why should prevention focus in the life cycle and not just with fetal and early childhood malnutrition?

Focus should be on preventing fetal and early childhood malnutrition, but the life cycle dynamics cause and consequence demand a holistic approach. Intervening at each point in the life cycle will accelerate and consolidate positive change.

Why is it important to frequently weigh and measure a child?

Health is influenced by the height and weight of a child. Weight can be a good indicator of malnutrition.

What indicator is used to measure progress in breaking the intergenerational cycle of malnutrition?

"Intrauterine growth retardation is a pivotal indicator of progress in breaking the intergenerational cycle of undernutrition, a prospective marker of a child's future nutrition and health status as well as a retrospective measure of the nutrition and health status of the mother."

What are the four types of malnutrition?

1. Overnutrition 2. Secondary Malnutrition 3. Micronutrient Malnutrition 4. Protein Calorie Malnutrition (AKA Protein Energy Malnutrition)

What is the result of good nutrition?

A diet that meets the requirements for an active, healthy life • Growth - will be growing under normal growth curves • Activity - enough energy to perform daily life functions • Productivity - not often sick or energy-depleted • Chronic disease prevention - heart disease, diabetes, cancer lung disease

What is the nutrition transition?

A term used to describe the changes in diet, physical activity, health and nutrition. Results from higher incomes, marketing, and changes in work and leisure activities.

What causes diarrhea in refeeding?

Activity of the brush border enzymes and the pancreatic enzyme secretion return to normal with refeeding. This results in a period of readaptation to food to minimize GI 'complaints' such as diarrhea, nausea, and vomiting.

What improves learning in children?

Alleviating hunger.

What has been hypothesized regarding in utero malnutrition and health in later life?

Barkers fetal origins of disease hypothesis: Nutritional insults during critical periods of gestation and early infancy, followed by relative affluence, increase the risks of chronic diseases in adulthood. Baby programmed for a life of scarcity and then confronted with a world of plenty. See increases in cardiovascular disease, diabetes and high BP. *there is a better explanation of this on the discussion handouts*

What were the physical and physiological symptoms exhibited during the semi starvation in the Keyes study?

Body weight decreased progressively to about 25% then plateaued. Muscle tone and HR decreased. After 3 months, participants complained of fatigue, muscle soreness, irritability, hunger pains. They exhibited a lack of ambition, self-discipline, concentration, happiness, mood control, tolerance for sneezing and heat.

What is the best way to feed an infant? Why?

Breast is best because infant does not compete with food supply, is it a clean food supply and it has immunologic benefits. Stronger intellectual development, reduced risk of cancer, obesity and chronic disease.

What actions have been recommended to support the feeding of an infant?

Breastfeeding with complementary feedings starting at 6 months with energy dense and micronutrient rich foods. Must be prepared, stored and fed in hygienic conditions.

What causes protein calorie malnutrition (AKA protein energy malnutrition)?

Caloric deficiency will cause protein deficiency due to nature of food supplies. Worsened by any accompanying illness.

Describe the changes in the use of carbohydrate, fat and protein during starvation

Carbohydrate is the first to be consumed in the form of fatty acids. At first, the brain continues to use glucose, because, if a non-brain tissue is using fatty acids, the use of glucose in the same tissue is switched off. After 2 or 3 days of fasting, the liver begins to synthesize ketone bodies from precursors obtained from fatty acid breakdown. The brain uses these ketone bodies as fuel, thus cutting its requirement for glucose. After several days of fasting, all cells in the body begin to break down protein. This releases amino acids into the bloodstream, which can be converted into glucose by the liver. Since much of our muscle mass is protein, this phenomenon is responsible for the wasting away of muscle mass seen in starvation. Hormonal changes will occur. Plasma insulin decreases, plasma cortisol and growth hormone stay the same and glucagon increases (up blood sugar). These changes are responsible for the mobilization and use of fat stores for energy. Starvation ensues when the fat reserves are completely exhausted and protein is the only fuel source available to the body.

What happens to the functional capacity of the heart during protein calorie malnutrition?

Cardiac function is reduced due to loss of ventricular size, CO and SV. If more oxygen is needed for the heart, HR must increase, which puts pressure on a weakened heart. Cardiovascular reflexes are altered, which can lead to postural hypotension and decreased venous return. Severe cases can lead to peripheral circulation failure similar to hypovolemic shock.

What are the common chronic diseases?

Cardiovascular disease Cancer Chronic respiratory diseases Diabetes

What are the major determinants of stunting?

Chronic low intake (poor diet and disease) leads to stunting.

Why is exploratory behavior so important in children?

Chronic malnutrition also has an indirect effect on mental development because it makes children less active and therefore their brains are less stimulated. Less exploratory behavior is evidence of this.

What is a common complication of refeeding? Why?

Congestive Heart Failure is a common complication of refeeding. Cardiac output can't increase enough to meet the needs from the increased plasma volume, increased oxygen consumption and increases in BP and HR.

What is the major effect of early life PEM?

Decreased brain growth (cell number and size), nerve myelination, neurotransmitter production, velocity of nervous conduction. Long-term implications because brain is growing in cell size and number - could affect learning.

What are the good and bad parts of nutrition transition?

Dietary changes have good and bad points: Good: Less undernutrition and communicable disease Bad: Higher risk of obesity and chronic disease.

What causes micronutrient malnutrition?

Dietary deficiencies of vitamin A, iodine, iron, zinc, vitamin D, C, B.

How long should you feed an infant? Why?

Exclusive breast feeding for 6 months - important growth, and storage of nutrients for immune and cognitive function.

What are the issues associated with availability, intake and absorption of iodine?

Found in populations where iodine-deficient soils produce crops that have low iodine levels (mountains and river valleys ), consumption of foods that contain goitrogens (prevent uptake of iodine in thyroid - cassava, soy, broccoli, cabbage), lack of access to iodized salt.

What impact does iron deficiency have on life?

Gastrointestinal disturbances, impaired cognitive function (not enough O2 to brain and lower amount of neurotransmitters), immune function, exercise or work performance, and body temperature regulation.

What nutrient is required for energy production and where does it come from when not in the diet?

Glucose is required for energy production and when not consumed naturally in the diet, it must be produced from the break down of protein (especially those of the muscle).

What impact does iodine deficiency have on life?

Goiter, impaired immunity and impaired mental function in adults.

Why is good nutrition important for the elderly?

Good nutrition is important for the elderly because nutritional status is related to functional ability. Elderly people can develop sarcopenia (the gradual loss of muscle mass with age) which is linked to age-related losses of strength, increased morbidity, functional impairment, dependence, and mortality. Data shows that energy and protein intake can directly affect this condition. Malnutrition leads to decreased functional capacity and need for more help. This means lower contribution to the family from the elderly. Malnutrition in the elderly is also linked to depression which leads to frailness and lack of ability to care for oneself.

What has been linked to the microbiome?

Gut microbiota influence the growth and differentiation of gut epithelial cells and play pivotal nutritive, metabolic, immunological and protective functions. Specifically the microbiome plays a role in: Efficient extraction of calories from ingested food. Enzymatic reactions in the microbiome aid in host homeostasis, food digestion/absorbtion, and synthesis of micronutrients (vitamins, H2, CO2 Methane, Lysine, conversion of urea to ammonia) Detoxification Epithelial Development Immune function (stimulates the growth of enterocytes, etc.)

What causes overnutrition?

Having too many cheap calories and consuming them in excess, thus too many calories and not enough exercise.

What dietary changes occur at the nutrition transition?

Indigenous diet, usually high in whole grains and starchy roots, is replaced by foods higher in fat, animal food sources and sugars.

What is the key indicator of malnutrition?

Infant Mortality Rate (number of children per 1,000 live births who die before their 1st birthday)

What are the physiologic effects of refeeding?

Insulin release is stimulated by the presence of protein and carbohydrates in the gut. Increases in HR, BP, O2 consumption and CO2 production.

What nutrient deficiencies are associated with decreased cognitive ability? How?

Iron is associated iron is required to transport oxygen, so with less iron, less oxygen is transported to the brain. Iodine is associated because deficiency can cause mental retardation in children due to poor neural growth. Low iodine can produce low TSH and impair working capacity in adults.

What are the major micronutrient deficiencies in the world?

Iron, Iodine and Vitamin A

What is "environmental enteropathy" and what is its' proposed mechanism?

It is a small intestinal disorder triggered by constant ingestion of feces. It results in leaks of bacteria through intestinal walls into blood that causes a low-grade infection that requires large amounts of energy to fight. Leaves fewer nutrients for growth - results in higher incidence of stunting.

What does stunting link to in adulthood?

It leads to later deficits in cognitive ability. It also leads to complications pregnancy.

What common condition have chronic diseases been linked to?

Large increases in chronic diseases associated with obesity have been documented around the developing world.

What are the dietary sources of iron?

Lean meat, seafood, nuts, beans, vegetables (spinach), fortified grains and dietary supplements

What are the dietary sources of vitamin A?

Liver/fish oils, milk, eggs, leafy green vegetables, yellow/orange vegetables, tomates, fruits, vegetable oils, dietary supplements

Who is affected by chronic disease?

Low, middle income countries. Poor people are much more likely to develop chronic diseases. Chronic diseases can cause significant financial burden and push individual and households into poverty. Almost half of chronic disease deaths occur prematurely, in people under 70. In low and middle income countries middle-aged people are especially vulnerable. Chronic disease affects men and women almost equally. People who aren't able to have equitable access to a healthy life and are not supported to make healthy choices

What are the 2 types of PEM?

Marasmus and Kwashiorkor

What are the metabolic effects of refeeding?

Metabolic consequences of refeeding include: Overfeeding carbohydrate can result in high blood sugars and dehydration. Phosphorous decreases in blood as it is taken up by cells. very low levels can lead to respiratory, cardiac, nervous system and red and white blood cell dysfunction. Potassium decreases in blood as it is taken into cells. This can cause irregular heart rhythm. Magnesium decreases in blood as it is taken into cell. Low levels may cause irregular heart rhythm, hypocalcemia, muscle weakness, and neurologic symptoms.

What are the symptoms of vitamin A deficiency?

Night blindness, dry skin, and frequent infections.

What impact does vitamin A deficiency have on life?

Night blindness, low iron status, increased severity and mortality of infections (low function of mucous and epithelial cells)

What fuels exploratory behavior in children?

Nutrients and food.

What is ORS and what is it used for?

ORS stands for Oral Rehydration Salts Solution. It is an inexpensive solution of sodium and glucoses used to treat acute diarrhea.

What is the problem in both industrialized and developing countries and why?

Obesity. Hard to access a balanced diet due to cost or water insecurity.

Who is most likely to be iron deficient?

Pregnant women (RBC production), infants and young children (quick growth), frequent blood donors (deplete iron stores), people with cancer (blood loss), people with gastrointestinal surgery/disorders (diet restriction, blood loss or poor absorption), people with heart failure (diet, malabsorption, medicine)

What are the issues associated with availability, intake and absorption of iron?

Pregnant women need more iron because they are producing more red blood cells. Infants and children need iron because of their quick growth, so iron-deficient mothers for breast milk or lack of iron-fortified food are problems.

Who is most likely to be vitamin A deficient?

Premature infants (low liver/plasma stores), infants and young children in developing countries (deficient breastfeeding), pregnant/lactating women in developing countries (fetal growth, tissues, metabolism), people with cystic fibrosis (pancreatic/fat insufficiency)

What is Marasmus?

Protein and energy and calorie deficit; exacerbated by infection or trauma or growth • Appearance: wasting, poor growth, hair is sparse, thin and dry without normal sheen, easily pulled out without pain • Skin dry, thin and with little elasticity and wrinkles easily • Patients are apathetic but usually aware and have a look of anxiety on their faces • Sunken cheeks due to loss of Bichat fat pads • Large amounts of food are not tolerated - vomiting and diarrhea

What is Kwashiorkor?

Protein deficiency; exacerbated by infection, trauma or growth • Appearance/physical signs: soft, pitting edema, dry skin with lesions ("flaky paint"), hair brittle, without normal sheen, can be pulled out easily • Curly hair becomes straight and hypo pigmented • Can have banding of hair due to periods of malnutrition and adequate nutrition • Associated with low protein-to-energy ratio in diet, hypoalbuminemia, fatty liver, edema • Caused by diet, infection or other stress, vitamin B deficiency, gut microbiome

What happens in the adolescent period that challenges nutrition?

Puberty. Adolescent hormonal changes accelerate growth. Problems can arise in adolescent girls who become pregnant as both the girl and the fetus will be competing for resources.

What is RUTF, under what circumstances is it used, and what are the advantages of it?

RUFT is Ready-to-use Therapeutic Food. It is a home-based treatment for severe acute malnutrition children who have no medical complications and still have an appetite. Provides foods that are safe to use at home and ensure rapid weight gain. RUTF is a ready-to-use paste in packets that doesn't need to be mixed with water. Brand name: "plumpy nut"

What are the issues associated with availability, intake and absorption of vitamin A?

Rare in developed countries. In developing countries, there is limited access to animal-based food sources and beta-carotene. In infancy, infants do not receive an adequate supply of breastmilk. Young children can have chronic diarrhea.

What causes secondary malnutrition?

Results from a condition that prevents proper ingestion, digestion or absorption metabolism. Causative conditions include: loss of appetite, change in normal metabolism due to infection (need more nutrients), diversion of nutrients due to parasitic agents (loss of appetite and nutrient consumption), "environmental enteropathy".

What are the dietary sources of iodine?

Seafood (seaweed), dairy products (milk), eggs, grains, iodized salt, breast milk and dietary supplements

What besides nutrients must be part of the therapy for malnourished children?

Sensory stimulation and emotional support. This includes: TLC, a cheerful, stimulating environment, structured play therapy, physical activity when the child is well enough and maternal involvement as much as possible.

When should complementary foods be introduced to feed and infant? Why?

Starting at 6 months of age to provide adequate nutrition and stimulate development and prevent diarrhea.

Why are continuing studies on children who have been treated for malnutrition necessary/of interest?

Studies of children and health risk found that in the thinnest children, the more obese they became as adults, the greater was their risk of developing chronic diseases. It is important to continue to do research in order to understand how those children continue to develop (catch up growth).

What is the link between poverty and obesity?

Studies show that there is a link with obesity and food insecurity in women and non-Hispanic older white girls (Not seen in men and younger children) It is proposed that this may be due to disordered eating. "Feast and famine," preoccupation with food and binging when food is available. It could also be due to types of food eating due to cost, availability and marketing. Energy dense, low nutrient foods are generally inexpensive. Few opportunities for physical activity, high stress levels, and early poverty associated with obesity in young adults are also all valid propositions.

What problems may stunted women have during pregnancy and delivery?

Stunted women have smaller babies. The smaller pelvic area also results in higher incidence of difficult births.

What is stunting? Wasting? Underweight?

Stunting is low height-for-age, wasting is low weight-for-height and underweight is low weight-for-age.

How did the subjects in the Keyes study adapt to semi starvation?

Subjects lost active tissue (lost lean body mass, 1/3 of weight lost from body fat) and reduced activity to save energy (decreased BMR due lean body mass, less heat due to less food, reduced mobility due to less caloric intake)

How long did the full recovery take in these study subjects?

The desire for more food and a feeling of fatigue continued, even after 12 weeks of rehabilitation due to organ shrinkage. Full recovery required 33 weeks.

What sign indicates that a child is entering the rehabilitation phase? What is encouraged at this point?

The return of appetite is the sign for entering the rehabilitation phase. During this phase very high intakes are encouraged to support a weight gain of over 10g/kg/day.

What are the symptoms of iodine deficiency?

Thyroid enlargement, mood imbalances, slowed brain function, slowed metabolism, low immunity.

What must people have to make good choices about diet?

To be food secure, families need sufficient resources to produce or purchase adequate food. People also need an understanding of what constitutes and appropriate diet for good health, and they must have the skills and motivation to make the best food choice available to them."

Why must refeeding be done slowly?

To let the body adjust to its new state. Effects (of refeeding) are most significant in the first few days of refeeding and it may take 1 week to adapt to the increase oxygen demand. Also organs need time to grow again.

What are modifiable risk factors for chronic disease?

Unhealthy diet Physical inactivity Tobacco use Harmful use of alcohol

What nutrient deficiency has a decrease in immune function before the presentation of more obvious clinical signs?

Vitamin A - decreased infection response (macrophage, NT killer, B cell) and mucous production

What nutrient has been successfully supplemented in the diet via sugar? Salt?

Vitamin A can be in sugar and iodine in salt

What might happen to the capacity to work with malnutrition?

Will have trouble learning, problems thinking, problems staying awake, lack physical strength or energy, or desire to work.

What decreases with malnutrition in adults?

Work capacity and productivity

What is the relationship between toilets and stunting?

~1 billion people worldwide practice open defecation. Open defecation can pollute soils and water sources, which can in turn lead to pollution of drinkable water and sanitation water for bathing and cooking due to poor disposal of fecal matter. This can lead to diarrhea or environmental enteropathy, which would result in lower nutrient intake and thus stunted height. Toilets prevent the pollution of natural resources and in turn of the humans that consume them.

What is the result of the changes in the immune system during protein energy malnutrition?

• Alteration in monokine metabolism (low proliferation of T cells) • Depletion of lymphocytes from the thymus and atrophy of the thymus gland • Cells from the t-lymphocyte regions of the spleen and lymph nodes are depleted due to thymic factors • Production, functions, and activity of the complement system and opsonic activity of serum are depressed, which may explain high susceptibility to gram negative bacterial sepsis • Phagocytosis, chemotaxis, and intracellular killings are also impaired • B-lymphocytes are relatively normal but may be defects in antibody production, such as secretory IGA (predispose to infection)

Why is obtaining iron and vitamin A different from animal vs. plant sources?

• Animal sources (pre-formed vitamin A, heme iron) ~90% is absorbed • Pro-vitamin A sources (carotenoids from plants) and nonheme is dependent on type of plant source and fat content of the meal

How is nutritional status assessed?

• Clinical assessment - mucous membrane, fluids, skin condition • Biochemical assessment - blood sample: Hb, cholesterol, etc. • Dietary assessment - dietary patterns and intake • Anthropometric assessment - body compartments • Height, weight, body composition, BMI • GROWTH! - no stunting or wasting • Z-score: number of SDs above or below the mean (-2 SD: lowest and -3 SD: severe malnutrition)

What happens to the functional capacity of the lungs during protein calorie malnutrition?

• Expiratory and inspiratory muscles are catabolized • Reduction in diaphragmatic mass is proportional to the loss of body weight • Decreased respiratory muscle strength, maximum voluntary ventilation, vital capacity and maximum inspiratory pressure

How does the body adapt physiologically to PEM?

• Insulin levels are low (changes hormones and affects thyroxine and lower thermogenesis and BMR or oxygen consumption) • Non-vital hormone secretion decreases (ex. sex hormones) • RBC production decreases (due to decreased O2 demands for lower lean body mass) • Heart muscle reduces in size proportional to loss of lean body mass (less O2, blood, cardiac contractile and sarcoplasmic proteins needed) • HR and BP decrease • Central circulation over peripheral circulation • Decreased renal plasma flow and glomular filtration due to decreased cardiac output (no effect on water clearance and concentration of urine)

How does the body adapt metabolically to malnutrition?

• Negative nitrogen balance - 1st 5 to 7 days. 12 to 15 grams of nitrogen per day is excreted in the urine. Skeletal muscle is broken down to produce glucose (gluconeogenesis). About 160 gm per day of body fat is also used. • Shift in metabolic fuels - first glucose is produced from protein breakdown to provide energy, then fat breakdown and metabolism provides ketones for all tissues except CNS, RBC and WBC. • Serum fatty acid levels increase • Weight loss - first week 0.7 to 1.3 kg per day, much of which is salt and water loss. After the first week 0.3 to 0.5 kg/day . • Basal Metabolic Rate and Total Energy Expenditure decrease activity, increased sleep and decrease in body temperature

What is the effect of maternal nutrition on the fetus?

• PEM in early pregnancy resulted in increased rate of fetal loss/malnutrition • PEM late in pregnancy resulted in low birth weight • Anemia resulted in low birth weight/iron stores/cognition • Iodine deficiency resulted in cretinism • IUGR - shorter, lighter, weaker, ADD and immune function impairment

Why is there diarrhea with severe PEM?

• Severe protein deficiency leads to poor intestinal absorption of fats and sugars due to decreased production of enterocytes and height of villi • Decrease in gastric, pancreatic and bile production with normal to low enzyme and conjugated bile acid concentration • Due to these changes, get diarrhea when fed because of irregular gastrointestinal motility and GI bacterial overgrowth • Low blood protein levels leads to intestinal edema which decreases luminal absorption which leads to diarrhea.

What is the effect of electrolyte changes on muscle tissue?

• Total body potassium is reduced due to loss of muscle proteins and intracellular potassium with decreased body size • Decreased amounts of ATP, due to decreased energy substrates, probably changes cellular exchange of sodium and potassium • When Na-K-ATP pump is not working (decreased ATP), results in potassium loss and increased intracellular sodium (over hydration) • Increased fatigability and reduced strength of skeletal muscle