Unit 11 Nutrition
ALTERATIONS IN NUTRITIONAL STATUS
Nutritional Needs
Dietary Reference Intakes
Dietary Reference Intakes (DRIs): A set of nutrient-based reference values with specific uses.
1) Recommended Dietary Allowance (RDA): Defined intakes meeting the nutrient needs of almost all healthy individuals of a particular assigned-at-birth sex and in a specific age range.
Most recent guidelines carbohydrates but not for fats.
2) Adequate Intake (AI): Set when there is insufficient scientific evidence to estimate an average requirement.
Derived from experimental or observational data
3) Estimated Average Requirement (EAR): Intake that meets the estimated nutrient need of half of individuals in a specific group.
Used as the basis for developing the RDAs.
4) Tolerated Upper Intake Level: Maximum intake that is judged unlikely to pose a health risk in almost all healthy individuals in a specified group.
5) Acceptable Macronutrient Distribution Range (AMDR): Outlines recommended fat intake expressed as a percentage of overall dietary intake rather than a set level.
Usage of DRIs:
Published by the National Academy of Science and periodically updated.
Used to advise about the level of nutrients needed to decrease the risk of chronic diseases.
Current recommended DRIs are available from the USDA Food and Nutrition Information Center.
Daily Values (DVs): Food and supplement labels use daily values set by the US FDA, based on older data than the data used to determine the DRIs
Calories
Energy Requirements: Greater during growth periods.
At the time of birth, a neonate requires 115 kcal/kg of body weight.
An infant requires 105 kcal/kg of body weight at one year of age.
Children aged 1-10 require 80 kcal/kg of body weight.
During adolescence:
Assigned-at-birth males require 45 kcal/kg of body weight.
Assigned-at-birth females require 38 kcal/kg of body weight.
During pregnancy, a gestational carrier needs an additional 300 kcal/day above their usual requirements; and an additional 500 kcal/day during the first three months of lactation
Proteins
Proteins: Required for growth and maintenance of body tissues, enzymes, antibody formation, fluid and electrolyte balance, and nutrient transport.
Composed of Amino Acids: Nine essential amino acids that must be derived from dietary sources:
Leucine, isoleucine, methionine, phenylalanine, threonine, tryptophan, valine, lysine, and histidine.
Complete Proteins: Foods providing adequate amounts of essential amino acids.
Most complete proteins are derived from animal sources.
Soy and quinoa are complete protein sources from vegetables.
Most vegetable proteins need to be combined to meet amino acid requirements.
Average Daily Protein Requirement: 30-50 g, provided the protein is of good quality and the overall diet is adequate in carbohydrates and fats
Fats
Fats: The most concentrated source of energy.
AMDR for Fat:
20-35% of daily caloric intake in adults.
25-35% of daily caloric intake in children aged 4-18 years.
30-40% of daily caloric intake in children aged 1-3 years.
Daily Dietary Recommendation for Cholesterol: < 300 mg daily.
Excess cholesterol can lead to significant harm to the cardiovascular system and increase the risk of cardiovascular diseases.
Impact of No-Fat Diets: Can interfere with the absorption of fat-soluble vitamins (A, D, E, K)
Omega-3 and Omega-6 Fatty Acids:
Omega-6: Increase inflammation, blood clotting, and cell proliferation.
Omega-3: Decrease inflammation, blood clotting, and cell proliferation
Carbohydrates
Dietary Carbohydrates: Complex carbohydrates, simple sugars, and indigestible carbohydrates (fiber).
Complex Carbohydrates: Rich in vitamins, minerals, and fiber; recommended over simple carbohydrates.
Carbohydrate Requirements:
No specific daily dietary requirements; all energy requirements can be met by proteins and fats.
However, protein sources are high in fat and more expensive.
Carbohydrate-Deficient Diets: Result in loss of tissue proteins and ketosis.
Quantity required to prevent ketosis and tissue wasting: 50-100 g/day.
AMDR for Carbohydrates: Intake should consist of 45-65% of the daily diet
Vitamins and Minerals
Vitamins: Group of organic compounds that act as catalysts in chemical reactions in the body.
Cannot be classified as a vitamin unless deficiency leads to disease.
Necessary for formation of RBCs, hormones, genetic materials, nervous system, and normal growth and development
Types of Vitamins:
Fat-Soluble Vitamins: A, D, E, K - stored in the body, can reach toxic levels.
Water-Soluble Vitamins: Nine required, including Thiamine, Riboflavin, Niacin, B6, Pantothenic acid, B12, Folic acid, Biotin, and Vitamin C - excreted in urine, seldom toxic
Minerals: Serve many essential functions.
Components of vitamins, hormones, and enzymes.
Help maintain acid-base balance and osmotic pressure in body compartments.
Macrominerals: Present in large amounts, including Calcium, Phosphorus, Sodium Chloride, Potassium, Magnesium, and Sulfur.
Trace Minerals: Present in small quantities, including Iron, Manganese, Copper, Iodine, Zinc, Cobalt, Fluoride, and Selenium.
Minerals maintain physiological hemoglobin levels, assist in nervous system function, and support muscle contraction and skeletal development
Fiber
Total Fiber: Composed of nondigestible carbohydrates found in plants such as fruits, vegetables, beans, nuts, and whole grains.
Functional Fibers: Isolated nondigestible carbohydrates with beneficial physiological effects.
Bulking Effects of Fibers: Slow gastric emptying, increase satiety, enhance the rate of transport through the GI tract, increase stool bulk, and facilitate normal bowel movements.
Current Daily Dietary Fiber Recommendations:
Young adult assigned-at-birth males: 34 g; assigned-at-birth females: 28 g.
For individuals older than 50 years: 28 g for assigned-at-birth males; 22 g for assigned-at-birth females
Overweight and Obesity
Obesity: Excess body fat accumulation with multiple organ-specific pathologic consequences.
Obesity and overweight have become global health problems.
In the US: > 74% of adults have BMIs ≥ 25; > 42.4% have a BMI ≥ 30.
Higher prevalence of high BMIs among minority groups.
Approximately 18.5% of US children aged 2-19 years are considered obese; this percentage has more than tripled since 1980.
Body Mass Index (BMI)
Definition: Clinical measure of obesity and overweight based on height and weight measurements, correlating with body fat.
World Health Organization (WHO) Classification:
Overweight: BMI ≥ 25
Obesity: BMI ≥ 30
Definitions for overweight and obesity in children based on assigned-at-birth sex and age-specific percentiles:
BMI 85th-95th percentile: overweight (corresponds to adult BMIs of 25 and 30).
BMI ≥ 95th percentile: obese
Obesity Etiologies
Causes of Overweight and Obesity: Energy imbalance due to excessive caloric intake and insufficient physical activity.
Contributing Factors:
Genetic, environmental, hormonal, socioeconomic, cultural, and psychological factors.
Health conditions (e.g., thyroid disorders, Cushing syndrome, polycystic ovarian disorder) and medications contributing to weight gain.
Genetics and Obesity: Complex relationship, with behavior-based interventions possibly helping to manage genetic influences
Environmental Influences: Major contributing factors include high availability of calorie-rich foods and few opportunities for physical activity.
Psychological Factors: Eating may serve as a coping mechanism for stress, boredom, or anxiety, though these relationships are complex.
Cultural and Socioeconomic Impact: Cultural food choices and behaviors are associated with overweight and obesity, relationships are complex and not fully understood
Types of Obesity
Classification by Body Fat Distribution:
1) Upper Body Obesity:
Also known as central, abdominal, visceral, or assigned-at-birth male (“android”) obesity - described as apple-shaped.
2) Lower Body Obesity:
Also referred to as peripheral, gluteal-femoral, or assigned-at-birth female (“gynecoid”) obesity - described as pear-shaped.
Body Fat Differences: Generally, assigned-at-birth males have more intra-abdominal fat, and assigned-at-birth females have more subcutaneous fat.
Aging Effects on Fat Distribution: Older assigned-at-birth males have an increasing proportion of intra-abdominal fat, and post-menopausal assigned-at-birth females also tend to acquire more central fat distribution (Tucker & Tucker, 2024, p. 1205).
Waist-to-Hip Ratio: Determines obesity type by comparing waist and hip measurements.
A waist-to-hip ratio > 1.0 for assigned-at-birth males and > 0.8 for assigned-at-birth females indicates central obesity (upper body)→higher health risks.
presence of excess fat in the abdomen, out of proportion to total body fat,
Central obesity can be evaluated further through imaging techniques such as CT or MRI scans.
Peripheral Obesity: Associated with less cardiometabolic risk than central obesity
Health Risks: Excess abdominal fat is a predictor of health risks and mortality
Waist Circumference: Better predictor of health risk than BMI; > 88 cm (35 inches) in assigned-at-birth females and > 102 cm (40 inches) in assigned-at-birth males are associated with increased health risks.
Weight Loss: Often results in the preferential loss of visceral fat, improving metabolic and hormonal abnormalities
Health Risks Associated with Obesity
Increased Risks: Obesity elevates risks for various conditions including:
Stroke, cancer, diabetes, kidney disease, heart disease, and respiratory diseases.
Impact on Body Systems:
Cardiac disease risk increases alongside hypertension, hypertriglyceridemia, and decreased HDL cholesterol levels.
Significant weight gain relates to T2DM, obstructive sleep apnea, gastric reflux, gallbladder disease, urinary stress incontinence, and joint disorders due to limited mobility
Reproductive Implications for Assigned-at-birth Females: Obesity can lead to infertility, higher-risk pregnancies, gestational diabetes, hypertensive disorders, and complications in births. Offspring often exhibit increased macrosomic rates with higher likelihood of Cesarean births associated with maternal obesity .
Cancer Correlation: Higher frequencies of certain cancers (endometrial, colon, gallbladder, prostate, kidney, postmenopausal breast cancer) in individuals with BMIs ≥ 30.
Life Expectancy: Adults with a BMI > 40 can have reduced life expectancy by 6-13 years
Prevention and Treatment of Obesity
Challenges in Managing Obesity: Few successful long-term interventions currently exist; effective approaches often focus on lifestyle behavior changes, which promote healthier food choices and increased physical activity.
Public Initiatives: Federal and state agencies are engaged in efforts for public education and policy to address obesity prevention and treatment.
Treatment Recommendations: Individuals with a BMI ≥ 30, those with a BMI of 25-29.9 with high waist circumference, or those with two or more identified health risk factors should receive individualized treatment focusing on healthy food choices, reduced calorie intake, increased physical activity, and behavior adjustments
Undernutrition and Eating Disorders
Undernutrition: A significant global health issue, with 98% of undernourished individuals in resource-limited countries; prevalent in pediatric and older adult populations of high-resource countries
Malnutrition and Starvation
Conditions: Malnutrition and starvation involve inadequate nutrient intake or inability to utilize nutrients for bodily functions.
Causes of Malnutrition: Poverty, unawareness, acute and chronic illnesses, self-imposed dietary restrictions.
Vulnerable groups include the unhoused, older adults, and children from resource-limited families.
Risk Factors: Fad diets limiting essential nutrients and disordered eating patterns (e.g., bulimia, anorexia, and less overt forms) increase malnutrition risk.
Malnutrition Related to Illness: Can occur secondary to chronic illnesses (e.g., liver disease, Crohn’s disease, cancer, depression/anxiety)
Protein-Energy Malnutrition
Conditions: Major form of malnutrition involving depletion of lean body tissues due to starvation or a combination of starvation and catabolic stress.
Children in resource-limited countries
Types of Protein and Energy Malnutrition:
1)KNOW THIS ONE→ Protein AND Calorie Deficient→ Marasmus: Progressive loss of muscle mass and fat stores due to inadequate food intake lacking both calories and proteins.
Characteristics:
Growth failure
Protuberant abdomen due to muscle hypotonia
Wrinkled skin
Hair that is dry and sparse
Cardiac complications (e.g., bradycardia, low blood pressure)
Borderline Hypothermia
2) High Carbs but Protein Deficiency→ Kwashiorkor: Protein deficiency in a diet high in carbohydrates. More severe form of malnutrition than protein and calorie deficiency(marasmus)
More severe form of malnutrition than protein and calorie deficiency
(marasmus)
Edema, desquamating skin, discolored hair, anorexia, and extreme apathy
Skin lesions.
Discolored hair→ red, sandy, “flag sign”
Anorexia
Growth failure
Manifestations of hypoalbuminemia
3) Marasmus-Kwashiorkor: Advanced protein-energy deficit with associated edema and rapid loss of anthropometric measurements.
Fatty degeneration in organs→ heart and liver etc
Cardiac dysfunction
Loss of subcutaneous fat: markedly ↓ the body’s capacity for temperature regulation and water storage
Malnourished kids→ dehydrate and hypothermic faster than nourished kids
Failed immune system→ unable to mount a fever response
Most effected kids asymptomatic infections
Malnutrition in Trauma and Illness
Occurrence: In resource-rich societies, occurs mainly due to trauma or illness→ major burns, sepsis, trauma
Marasmus-like Malnutrition: Seen in chronic diseases such as COPD, congestive heart failure, cancer, and HIV infection.
Nearly 50% of cancer patients experience muscle-wasting.
Protein breakdown is accelerated, hindering rebuilding processes in critical organ systems
Consequences:
Loss of immune cells
Compromised wound healing leads to higher morbidity and mortality rates.
Cardiac→ low contract contractility
Respiratory function is decreased
Eating Disorders
Definition: Serious disturbances in eating behaviors, often linked to excessive concerns about body shape or weight, affecting individuals across various demographics, especially more prevalent in assigned-at-birth females.
Contributing Factors: Genetic, metabolic, neurochemical, sociocultural pressures, mood, anxiety, and personality disorders.
Common Eating Disorders: Anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED)
Anorexia Nervosa
Characteristics: Begins typically in adolescence, prevalent in young assigned-at-birth females
Determined dieting (most prevalent approach to controlling body weight) with a goal of sustained low-weight
Symptoms include compulsive exercise, amenorrhea, and severe caloric restriction.
Etiological factors include genetic predispositions, perfectionism, anxiety, and sociocultural pressures
Associated Manifestations:
Most frequent: amenorrhea and loss of secondary sex characteristics with ↓ levels of estrogen leading eventually to osteoporosis ~ bone loss can occur
Constipation, cold intolerance, body weight at least 15% below expected and potential severe cardiac issues (e.g., bradycardia, hypotension).
Brain volume loss noted during malnutrition episodes.
Diagnosis Criteria:
Inclusion of refusing to maintain minimal body weight
Intense fear of gaining weight
Distorted self-perception of body size or weight.
Common coexisting psychiatric disorders include major depression, OCD, and substance use disorders
Bulimia Nervosa
Characteristics: Involves recurrent binge eating and compensatory behaviors such as self-induced vomiting, excessive exercise, fasting, or laxative abuse.
Typically affects individuals at a normal weight.
Physical Manifestations:
GI disorders→ esophagitis, dysphagia, and esophageal stricture
Dental problems→ Tooth enamel erosion (most noticeable)
Fluid-electrolyte imbalances
Weight may fluctuate but not to the scale seen in AN
Diagnosis Criteria:
Recurrent binge eating (at least 2X/week; X3 months)
Inappropriate compensatory behaviors
Self-evaluation unduly influenced by body shape and weight
Associated mental health disorders
two (2) BN subtypes distinguishing
1) those who compensate by purging (e.g., vomiting or overuse of laxatives or diuretics)
2) those who use non-purging behaviors (e.g., fasting or excessive exercise)
Eating Disorder Not Otherwise Specified (EDNOS)
Definition: ENOS encompasses various eating disorders not meeting full criteria for AN or BN.
Binge-Eating Disorder (BED):
Dx criteria: recurrent episodes of binge eating at least two (2) days/week X six (6)
months; and meeting at least three (3) of the following criteria:
o Eating rapidly
oEating until becoming uncomfortably full
oEating large amounts when not hungry
oEating alone due to embarrassment
oDisgust, depression, or guilt because of eating episodes
Majority of individuals affected by BED are overweight or obese per BMI criteria
Individuals with BMI ≥ 30 have a higher incidence of BED than individuals with BMI < 30