Element | Symbol | Percentage of total body mass |
---|---|---|
oxygen | O | 65.0 |
carbon | C | 18.5 |
hydrogen | H | 9.5 |
nitrogen | N | 3.2 |
calcium | Ca | 1.5 |
phosphorus | P | 1.0 |
potassium | K | 0.4 |
sulfur | S | 0.3 |
sodium | Na | 0.2 |
chlorine | Cl | 0.1 |
magnesium | Mg | 0.1 |
iodine | I | 0.1 |
iron | Fe | 0.1 |
Animal-derived foods | Protein content/% | Plant-derived foods | Protein content/% |
---|---|---|---|
cheese (Cheddar) | 26 | soya flour (low fat) | 45 |
chicken (no skin) | 25 | soya flour (full fat) | 37 |
bacon (lean) | 20 | peanuts | 24 |
beef (lean) | 20 | bread (wholemeal) | 9 |
Cod | 17 | bread (white) | 8 |
Herring | 17 | rice | 7 |
Eggs | 12 | peas (fresh) | 6 |
Milk | 3 | potatoes (old) | 2 |
cheese (cream) | 3 | bananas | 1 |
Butter | less than 1 | apples | less than 1 |
Essential amino acids | Amino acids synthesised from essential amino acids | Non-essential amino acids |
---|---|---|
lysine (Lys) | tyrosine (Tyr)* | glycine (Gly) |
methionine (Met) | cysteine (Cys)† | alanine (Ala) |
threonine (Thr) | serine (Ser) | |
leucine (Leu) | proline (Pro) | |
isoleucine (Ile) | glutamate (Glu) | |
Valine (Val) | glutamine (Gln) | |
phenylalanine (Phe) | aspartate (Asp) | |
tryptophan (Try) | asparagine (Asn) | |
histidine (His) – made only in very small amounts in the body | ||
arginine (Arg) – for young children |
Name of element | Chemical symbol | Number of bonds |
---|---|---|
Carbon | C | 4 |
Nitrogen | N | 3 |
oxygen | O | 2 |
hydrogen | H | 1 |
Name and pronunciation | Formula of R group |
---|---|
glycine (‘gly-seen’) | |
phenylalanine (‘fee-nile-alla-neen’) | |
lysine (‘lie-seen’) alanine (‘alla-neen’) | |
alanine (‘alla-neen’) | |
aspartate (‘ass-part-ate’) | |
serine (‘seer-een’) | |
cysteine (‘sis-tayn’) |
Gender and age | Estimated average requirement, EAR/g per day | Reference nutrient intake, RNI/g per day |
---|---|---|
Men | ||
19–50 years | 44.4 | 55.5 |
over 50 years | 42.6 | 53.3 |
Women | ||
19–50 years | 36.0 | 45.0 |
over 50 years | 37.2 | 46.5 |
Meal | Food eaten | Estimated protein content/g |
---|---|---|
Breakfast | Cereal with milk (8 g per 40 g serving, with milk, according to packet) | 8 |
Lunch | White bread, 100 g (8% protein) | 8 |
Cheese, 50 g (26% protein) | 13 | |
A little butter (less than 1% protein) | negligible | |
6 cherry tomatoes | unknown | |
Piece of fruit cake | unknown | |
Banana, 120 g fruit (1% protein) | 1.2 | |
Evening meal | Beef stew, made with 150 g beef (20% protein) | 30 |
Baked potato, 150 g (2% protein) | 3 | |
Frozen green beans, 75 g (1.3 g per 75 g serving, according to packet) | 1.3 | |
Yoghurt, 150 g (5 g protein per 100 g) | 7.5 | |
Hot drinks | Made with about 150 ml milk (about 150 g, with 3.4 g protein per 100 g, according to carton) | 5.1 |
Snack | Apple, 100 g (less than 1% protein); cheese, 25 g (26% protein) | about 6 |
Total protein | about 83 |