Diet Flashcards
Essential Dietary components
-Carbohydrates
-Lipids
-Protein
-Fibre
-Vitamins
-Minerals
-Water
Carbohydrates purpose, structure and formula
Energy source
CHO contain aldehyde groups and Keto groups
Many hydroxyl groups -OH
Lipids structure and function
Glycerol molecule with fatty acid chains esterified onto it
Energy source
Absorption of fat soluble vitamins (A,D,E,K)
Obtain essential fatty acids
What is the function of dietary protein?
Provide essential amino acids
Synthesis of N containing compounds
What is the importance of Fibre ?
Normal GI function
Lowers blood cholesterol
Reduces bowel cancer incidence (Cells use energy that bacteria release from digesting fibre, low fibre means cell death, more mitosis = more cancer risk)
Vitamins
Essential for life, without = deficiency disease
Vitamin deficiency diseases/roles
Vit A - Xerophthalmia (affects eye)
Vit E - Neurological abnormalities/protects against lipid peroxidation (oxidative stress)
Vit D - Rickets (Kids, no hydroxyapatite deposited in bones so poor mineralisation)
Vit K - Defective blood clotting
Vit C - Regenerates reduced Vit E (lipid per oxidation protection) SCURVY
Vit B12 - Anaemia
Vit B6 - Anaemia, Dermatitis
Minerals
Essential for life
Establish ion gradients
Calcium and phosphorus for bone and teeth structure
Calcium signalling molecule
Enzyme cofactors
Iron for haemoglobin
Daily energy expenditure 3 parts:
BMR (Basal Metabolic Rate)
DIT (Diet Induced Thermogenesis)
Voluntary Actions
BMR Definiton and % of body parts contribution
Energy used to maintain resting activities of the body
Skeletal Muscle = 30%
Liver = 20%. Liver and Brain same cuz both big
Brain = 20%
Heart = 10%
Others = 20%
Factors affecting BMR
Body SA
Age
Gender
Environmental Temp
Endocrine status (Hyperthyroidism = higher)
Body Temperature (HIgher = Higher)
Diet Induced Thermogenesis
Energy required to digest food
Voluntary actions/physical activity
Reflects energy demands of which muscles
Skeletal
Respiratory
Cardiac
Body Weight depends on what balance
Energy Intake and Energy Expenditure
Excess energy stored as what?
Lipids in Adipose tissue
Obesity defined by what?
BMI OVER 30
Obesity is a risk factor for
Cancers
Cardiovascular Diseases
Type 2 diabetes
BMI (Body Mass Index)
BMI = WEIGHT/HEIGHT^2
(KG/M^2)
BMI Categories and associated values
UNDERWEIGHT = <18.5
IDEAL WEIGHT = 18.5 - 24.9
OVERWEIGHT = 25 -29.9
OBESE = 30 - 34.9
SEVERELY OBESE = > 35
Alternate measurement than BMI is Waist/Hip ratio
It shows
Distribution of fat is important
Waist/Hip ratio value that indicates obesity
Men > 0.9
Women > 0.85
Increased risk factors with High waist to hip ratio
Insulin resistance
Type 2 diabetes
Hypertension
Hyperlipidaemia
Stroke
Protein-energy malnutrion conditions
Kwashiorkor
Marasmus
About Marasmus
Kids under 5
Emaciated, Muscle Wastage, Thin Dry Hair, Body Fat loss
NO OEDEMA
Kwashiorkor Signs/Symptoms
Pitting OEDMA
Low Serum Albumin
Anaemia
Lethargy
Anorexia
Explanation BEhind Kwashiorkor
Low protein = insufficient amino acids
Cant synthesis Albumin
Plasma Oncotic Pressure Decreases
Fluid accumulates in the Intersistium around capillaries causing OEDEMA
OEDEMA Causes Hepatmegaly and Ascites (fluid in peritoneal cavity0
Refeeding Syndrome
Rapidly Introducing energy rich foods to a malnourished/starving patient causes RAPID DEPLETION of already depleted electrolytes like PHOSPHATE, MAGNESIUM and POTASSIUM
How can Hypophosphataemia be caused?
Caused by Refeeding syndrome
How Refeeding syndrome causes electrolyte depletion (hypophosphataemia)
Sudden increase in glucose causes INsulin to be released causing increase in GLycogen , lipid and protein synthesis.
Processes us electrolytes
