Nutrition Lecture Flashcards
Macronutrients?
Carbs/Sugars
Amino acids
Fatty acids and lipids
Micronutrients?
Vitamins
Minerals
Water
Adequate diet?
Energy (carbs, fats, proteins)
Essential/Nonessential amino acids and fatty acids (building blocks for synthesis of structural and functional proteins and lipids)
Vitamins and minerals (coenzymes and hormones in metabolic pathways - calcium and phosphate)
Dietary Essentials?
Not produced by the body
Provided by diet
- Phenylalanine, leucine, isoleucine, methionine, valine, tryptophan, threonine, lysine
Dietary nonessentials?
Synthesized by body
- Glycine, serine, aspartic acid
Nutrient deficiencies?
Developing: Common undernutrition or protein-energy malnutrition
Industrialized: dietary impropriety can cause: atherosclerosis, cancer, diabetes, hypertension
Primary malnutrition?
One or all of the components are missing
Secondary or conditional malnutrition?
Supply of nutrients is adequate
Malnutrition occurs: nutrient malabsorption, impaired nutrient use of storage, excess nutrient losses, increased need
Reasons for deficiencies?
Poverty Infections Acute and chronic illnesses Ignorance and failure of diet supps Chronic alcoholism (thiamine, pyridoxine, folate, vit A) Self imposed: anorexia, bulimia
Nutritional Disorders
Protein-energy malnutrition
Anorexia or Bulimia
Vitamin Deficiencies
Mineral Deficiencies
Protein-Energy Malnutrition
Low body weight, fat storage and reduced plasma proteins
Determined by BMI
Children- loss of skeletal muscles and subq fat
25% in developing
High death rate among children >5 yo
Marasmus
Somatic protein compartment
- Severe reduction in caloric intake
60% reduction in weight
Kwashiorkor
Visceral protein compartment Protein deprivation African kids: weaned too early bc of another kid, receive exclusively carb diet Muscle and fat are not effected Causes fatty liver - Hypoalbuminemia + generalized edema
Consequences of Marasmus
Loss of muscle Growth retardation Subq fat used as fuel Head appears too large Anemia, multivitamin deficiences Immune deficiency
Related disease to kwashiorkor
Nephrotic syndrome Damaged kidneys After extensive burns Enteropathies after protein loss Non absorption of proteins because of chronic diarrhea
Anorexia
Self induced starvation
Similar to PEM consequences
Permanent effects of system
Amenorrhea: decreased secretion of gonadotropin-releasing hormone, luteinizing hormone, and follicle-stimulating hormone
Cold intolerance, bradycardia, constipation, change in skin and hair, decreased bone density, postmenopausal
Bulemia
Individual binges and pukes
Amenorrhea (less than 50%)
Medical complications: electrolyte imbalance (cardiac arrhythmias), pulmonary aspiration of gastric content, esophagel and cardiac rupture
Vitamin deficiencies
4 fat soluble
- more readily stored, poorly absorbed in GI of fat malabsorption
9 water soluble
Fat soluble
A
D
E
K
A
visual pigment and cell proliferation
D
Facilitates intestinal Ca and K absorption and bone mineralization
- synthesized endogenously
E
Antioxidant and radical scavenger
K
Cofactor in hepatic carboxylation of pro-coagulants –> bleeding disorders
- synthesized endogenously
Water soluble
B1 B2 Niacin B6 B12 C Folic Acid Pantothenic acid Biotin
B1
Thiamine
Pyrophosphate
B2
Riboflavin
Flavin nucleotides
Niacin
Incorporate into nicotinamide adenine nucleotides (redox rxn)
- synthesized endogenously
B6
Pyridoxine
Derivatives serve as coenzymes in rxns
B12
Required for folate metabolism and DNA synthesis
C
Serves in many redox rxns and hydroxylation of collagen
Folic acid
Essential cofactor for nucleic acid synthesis
Pantothenic acid
CoA
Biotin
Carboxylation rxns
- synthesized endogenously
Zinc deficiency
Oxidases
- rash around eyes, mouth, nose, and anus
- anorexia and diarrhea
- growth retardation
Iron deficiency
Hemoglobin
- anemia
Iodine deficiency
Thryoid hormone
- goiter and hypothyroidism
Copper deficiency
CytochromE C oxidase
- Muscle weakness
Neurologic defects
Fluoride deficiency
Dental caries
Selenium deficiency
Glutathione peroxidase and antioxidant
- Cardiomyopathy
Obesity
Sedentary lifestyle, socioexconomic conditions, availability of processed, high calorie foods, soft drinks
- BMI, skin fold measurement, body circumference (hip to waste)
- Increased morbidity and mortality
- Prevention and management
BMI
703* (weight/ht^2)
25 normal
25-29.9 overweight
30+ obese
Central/visceral obesity
Accumulates fat in trunk and abs
- Higher risk of several diseases
Obesity etiology and definition
Genetic, environmental, psychological
- Disorder of energy balance; when food-derived energy exceeds energy expenditure, the excess calories are stored as TGs in fat tissue
- Intake vs expenditure
Energy expenditure
Basal energy expenditure
Thermic effect of food
Activity related expenditure
Basal energy expenditure
Energy for metabolic processes while at rest
- 69% of total
Thermic effect of food
Energy required for digestion and absorption of food
- 10% of total
Activity related expenditure
Varies with level of activity
- 20-30% of total
Hungry
Ghrelin goes up and activates anabolic circuit –> want to eat – increases leptin, insulin, and PYY, and reduces energy usage
- Ghrelin falls, inhibition
Hyperinsulinemia
Decreased IGFBP-1/2
Increased bioavailability of IGF-1 –> Increases free IGF-1 for increased cell proliferation and decreased apoptosis (increased risk of cancer)
Less obese, less
Adiponectin
- Sensitivity to insulin –> more secretion –> hyperinsulinemia
Total food intake (calories)
1000-2000 day
Carbs 50-60%
Fat 30%
Proteins 10-20%
