Topic 4: Protein and amino acids Flashcards
week 4 (19 cards)
What is the protein RDI for adult males?
0.85 g per kg of body weight per day.
What is the protein RDI for adult females?
0.75 g per kg of body weight per day.
What proportion of total energy intake should come from protein?
15-25% (AMDR).
How much protein should a 90 kg male consume daily?
Approximately 77 g/day (0.85 g/kg).
How much protein should a 57 kg female consume daily?
Approximately 43 g/day (0.75 g/kg).
What determines protein quality?
Amino acid content, digestibility, and bioavailability.
What is a high biological value (HBV) protein?
A protein containing all essential amino acids in adequate proportions.
Which food sources have the highest protein digestibility?
Animal proteins (90–99%), soy and legumes (~90%), plant proteins (70–90%).
What is a complementary protein?
Two or more incomplete proteins that together provide all essential amino acids.
Do complementary proteins need to be eaten at the same meal?
No, but they should be consumed over the course of the day.
What is protein turnover?
The continuous breakdown and synthesis of proteins in the body.
What happens to excess amino acids after deamination?
They are converted to urea and keto acids.
What is the main nitrogen waste product in protein metabolism?
Urea.
What dietary intake stimulates muscle protein synthesis (MPS)?
A high-quality protein dose of 20–30 g after resistance exercise.
Which protein source stimulates MPS most effectively?
Whey protein, due to rapid digestion and high leucine content.
What is marasmus?
A condition caused by deficiency in both protein and energy, leading to severe muscle wasting.
What is kwashiorkor?
A protein deficiency with adequate energy intake, characterized by oedema, fatty liver, and poor appetite.
Which condition presents with oedema due to low protein intake?
Kwashiorkor.
Which condition is marked by severe nutrient deficiency and prominent ribs?
Marasmus.
