Nutrition, Diet + Body Weight Flashcards
What is energy?
The capacity to do work
Define metabolism
The chemical processes that occur within a living organism in order to maintain life
What are the 4 metabolic pathways?
- oxidative - convert food into energy
- detoxification- removes toxins
- biosynthetic - produce basic building blocks for cells
- fuel storage +mobilisation pathways - ability to store excess fuel + mobilise the stores when needed
Compare and contrast exergonic + endergonic reactions
Exergonic - releases energy G<0
Endergonic - take energy in G>0
What are the 5 cellular processes which require energy to work?
biosynthetic work
transport work
mechanical work - muscles
electrical work - nerves
osmotic work - kidney
What do cells use to drive energy-requiring processes?
Chemical bond energy
What is 1 kcal?
Amount of energy needed to raise temp. Of 1 kg of water by 1°C
Energy in 1kcal
1kcal = 4.2Kj
What are 7 nutrients?
Macronutrients:
- carbs
- proteins
- fats
Micronutrients
- minerals
- vitamins
- water
- fibre > lowers cholesterol
General formulation for carbs
(CH2O)n
What are 9 essential amino acids?
If Learned This Huge List May Prove Truly Valuable
Isoleucine
Lysine
Threonine
Histidine
Leucine
Methionine
Phenylalanine
Tryptophan
Valine
What is an essential amino acid?
Can’t be synthesis
Must be obtained from diet
What amino acids are conditionally essential?
Children + pregnant women - Arginine, tyrosine, cysteine
Tyrosine - when phenylalanine levels are low
Cysteine - when methionine levels are low
Why do vegetarians and vegans need a ranged diet?
Plant proteins are ‘low quality’ as they are deficient in essential amino acids
Ranged diet means essential amino acids aren’t missed
Requirements of routine maintenance (IV fluids)
Na+, K+, Cl-: 1mmol/kg/day
Water: 30ml/kg/day
How much fibre is needed a day?
Where is it found?
18g/day
e.g. bread, beans, fruit + veg
What does fibre help prevent?
Constipation - something solid for bowels to push agaisnt
Bowel cancer - toxic waste removed faster
High cholesterol
Diabetes risk - slows sugar absorption
What is the daily energy expenditure the sum of?
BMR
Diet induced thermogenesis
Physical activity level
What is the basal metabolic rate?
Energy needed to keep your body alive at rest
Factors affecting BMR
Body size
Gender
Environment temperature
Endocrine status
Body temp
What is the daily energy expenditure with moderate physical activity of a 70kg male vs 58kg female?
Male - 12,000kJ/day
Female - 9,500kJ/day
How to calculate BMI
Weight (kg)/height^2(m)
What are the classifications of BMI?
underweight <18.5
desirable weight 18.5-24.9
overweight 25-29.9
obese 30-34.9
severely obese >35
What is Kwashiorkor disease?
Low plasma protein > low plasma oncotic pressure + severe oedema
Fatty liver due to lack of lipid transport molecules
Symptoms of Kwashiorkor
Oedema
Sparse hair
Moon face
Swollen abdomen
What is Marasmus?
Due to insufficient energy intake
Multiple nutritional deficiencies
Signs + symptoms of marasmus
Wasted appearance
Bradycardia
Hypotension
Anaemia
What should you re feed at?
5-10kcal/kg/day gradually over a week
Differentiate between marasmus + kwashiorkor in terms of:
- calorie intake
- protein intake
- oedema
- appearance
marasmus:
- calorie intake: inadequate
- protein intake: inadequate
- oedema: absent
- appearance: thin bony child
.
kwarshiorkor:
- calorie intake: poor-normal
- protein intake: inadequate
- oedema: present
- appearance: thin child with pot belly
What can re-feeding syndrome cause?
Confusion
Coma
Convulsion
Death
Due to electrolyte imbalance
