Nutrition and energy Flashcards
What is EAR?
Estimated Average Requirement
sufficient for 50% population
What is EAR?
Estimated Average Requirement
sufficient for 50% population
What is LRNI?
Lower Reference Nutrient Intake
sufficient for 2.5% population
What is RNI?
Reference Nutrient Intake
sufficient for 97.5% population
What is safe intake?
Sufficient for almost everyone but not so large as to cause undesirable effects
What is the safe upper limit?
highest level of intake likely to have no adverse effects
What 2 factors does energy expenditure depend on?
basal metabolic rate
amount and intensity of physical exercise
what factors contribute to basal metabolic rate?
age, weight, sex
what are macronutrients used for?
immediate energy generation
storage of fats, carbs and protein
XS carbs and proteins can be stored
proteins can’t be stored
fat stores form what % of total energy?
80-90% total energy source
what is the average daily requirement of protein?
0.75g/kg/day
70kg male -> 50g/day
athletes/ body builders -> 1.2-1.7g/kg/day
what is the daily turnover rate of proteins?
250g/day
3% / day
What is negative nitrogen balance?
nitrogen intake
what is positive nitrogen balance?
intake > excretion
pregnancy, growth
body building new tissue
What are the 9 essential AAs that must be obtained from the diet?
Many Very Happy Little Pigs Take Iced Lemon Tea
Methionine, Valine, Histidine, Leucine, Phenylalanine, Trytophan, Lysine, Threonine
which 3 amino accids are generally lacking in plant proteins?
cysteine, methionine, tryptophan
proteins in beans
methionine, cysteine = deficient
lysine = rich source
proteins in rice, nuts
lysine = deficient
rich source = methionine, cysteine
proteins in corn
deficient = lysine, tryptophan
rich source = methionine
how much energy does 1g fat provide?
9kcal
how much energy does 1g CHO or protein provide?
4kcal
What are cholesterol and fatty acids precursors for?
hormones, prostaglandins
Functions of adipose tissue?
unlimited storage
protects vital organs
bodies and face shape
what are triacylglycerides formed from?
3 fatty acids + 1 glycerol
what are the recommended fat intakes?
what are the 2 essential fatty acids from the diet?
omega 3 and omega 6
how many portions of oily fish should be eaten a week?
2 portions to reduce the risk of CHD
what are the 4 types of CHO?
polysaccharides - starch
disaccharides - sucrose
monosaccharides - glucose
non-starch polysaccharide - fibre
recommended intake of non-milk extrinsic sugars
what is the recommended total CHO intake?
50% daily intake
what are the risk factors associated with high sugar intake?
obesity
high levels of fructose -> metabolic syndrome, insulin resistance, DMT2
what are micronutrients and how much do we need?
vitamins = organic compounds, micrograms to mg minerals = inorganic elements, micrograms to mg to g (Na, Ca)
what are the 4 fat soluble vitamins?
K,A,D,E
which vitamins are not converted into coenzymes?
A,D,E
Thiamine (B1) - role and deficiency
cofactor in decarboxylation reactions
Beri-Beri; muscle weakness, nerve damage
riboflavin (B2) - role and deficiency
consitutuent of cofactors eg FAD
very rare - cofactors bind tightly to enzymes and efficiently conserved
Pantothenic acid (B5)
consitutuent of conenzyme A
Pantothenic acid (B5)
consitutuent of conenzyme A
What is LRNI?
Lower Reference Nutrient Intake
sufficient for 2.5% population
What is RNI?
Reference Nutrient Intake
sufficient for 97.5% population
What is safe intake?
Sufficient for almost everyone but not so large as to cause undesirable effects
What is the safe upper limit?
highest level of intake likely to have no adverse effects
What 2 factors does energy expenditure depend on?
basal metabolic rate
amount and intensity of physical exercise
what factors contribute to basal metabolic rate?
age, weight, sex
what are macronutrients used for?
immediate energy generation
storage of fats, carbs and protein
XS carbs and proteins can be stored
proteins can’t be stored
fat stores form what % of total energy?
80-90% total energy source
what is the average daily requirement of protein?
0.75g/kg/day
70kg male -> 50g/day
athletes/ body builders -> 1.2-1.7g/kg/day
what is the daily turnover rate of proteins?
250g/day
3% / day
What is negative nitrogen balance?
nitrogen intake
what is positive nitrogen balance?
intake > excretion
pregnancy, growth
body building new tissue
What are the 9 essential AAs that must be obtained from the diet?
Many Very Happy Little Pigs Take Iced Lemon Tea
Methionine, Valine, Histidine, Leucine, Phenylalanine, Trytophan, Lysine, Threonine
which 3 amino accids are generally lacking in plant proteins?
cysteine, methionine, tryptophan
proteins in beans
methionine, cysteine = deficient
lysine = rich source
proteins in rice, nuts
lysine = deficient
rich source = methionine, cysteine
proteins in corn
deficient = lysine, tryptophan
rich source = methionine
how much energy does 1g fat provide?
9kcal
how much energy does 1g CHO or protein provide?
4kcal
What are cholesterol and fatty acids precursors for?
hormones, prostaglandins
Functions of adipose tissue?
unlimited storage
protects vital organs
bodies and face shape
what are triacylglycerides formed from?
3 fatty acids + 1 glycerol
what are the recommended fat intakes?
what are the 2 essential fatty acids from the diet?
omega 3 and omega 6
how many portions of oily fish should be eaten a week?
2 portions to reduce the risk of CHD
what are the 4 types of CHO?
polysaccharides - starch
disaccharides - sucrose
monosaccharides - glucose
non-starch polysaccharide - fibre
recommended intake of non-milk extrinsic sugars
what is the recommended total CHO intake?
50% daily intake
what are the risk factors associated with high sugar intake?
obesity
high levels of fructose -> metabolic syndrome, insulin resistance, DMT2
what are micronutrients and how much do we need?
vitamins = organic compounds, micrograms to mg minerals = inorganic elements, micrograms to mg to g (Na, Ca)
what are the 4 fat soluble vitamins?
K,A,D,E
which vitamins are not converted into coenzymes?
A,D,E
Thiamine (B1) - role and deficiency
cofactor in decarboxylation reactions
Beri-Beri; muscle weakness, nerve damage
riboflavin (B2) - role and deficiency
consitutuent of cofactors eg FAD
very rare - cofactors bind tightly to enzymes and efficiently conserved
Niacin (B3) - role and deficiency
constituents of cofactors eg NADH
Pellagra -diarrhoea, depression, dermatitis, death
Pantothenic acid (B5)
consitutuent of conenzyme A
Biotin B (B7) - role and deficiency
prosthetic group, carrier for CO2
Pyroxidal phosphate (B6)
cofactor for enzyme in protein metabolism, haem synthesis, NT synthesis, modulated steroid hormone action
irritability, depression, confusion, inflammation of tongue and mouth
Folic acid (B9)
1-C transfers
neural tube defects - spina bifida, anencephaly, macrocytic anaemia
cobalamin (B12)
methionine synthesis, odd-chain fatty acid metabolism
macyrocytic anaemia, neurological damage, commonly caused by autoimmune disease -> malabsorption
vitamin C
collagen synthesis
scurvy
vitamin D
bone formation and maintenance, immune regulation,cell differentiation, muscle function
rickets in children
osteomalacia in adults
vitamin E
anti-oxidant, prevent lipid oxidation in membranes
deficinecy if problem absorbing fats -> neurological problems
vitamin K
cofactor for blood clotting enzymes
bone maintenance
deficiency in newborns -> bleeding
babies given it at birth
what are the 7 key minerals?
iron fluoride calcium magnesium zinc iodine phosphate
what is the recommended sodium intake?
what is malnutrition?
inadequate or excess intake of protein, energy, micronutrients
what are the 4 most important micronutrient deficiencies worldwide?
iron, zinc, iodine, vitamin A
seasonal and geographical variation in Vitmain D deficiency
Vit D formed in skin in presence of UV light
adults - osteomalacia children - rickets
increased risk -> auto-immune diseases, some cancers, muscle weakness in elderly
Dietary vitamin B12 deficiency
seen in vegans (B12 only from animals)
absoprtion dependent on presense of intrinsic factor -> binding
deficiency -> anaemia, neurological damage, numbness and tingling of fingers and toes
advice for taking folic acid supplements?
females who could get pregnant or in first 3 months of pregnancy
what is the effect of inadequate iodine in pregnancy?
cognitive outcomes of children
guidelines for taking vitamin A, D, C
children
10micrograms vitamin D daily
adults if asian orgin, rarely outdoor, no meat or oily fish