Fruit Contains All Required Protein
In Short :
Even consuming (the right-) fruits only, you will absorb all protein you need. Consuming a little fresh raw animal food every once and a while too, abundantly supplies you with protein. These foods combined also contain all other nutrients you need.
Consuming too much protein can cause depressions, sleeplessness (see site13) and vitamin D deficiency, and lack of vitamin B2, B6 and folic acid for these are required to process protein.
It's best to combine fruits with some (fresh raw-) foods containing high-quality protein. In relation to human requirements, protein quality of Brazil nuts in particular, and raw fish in general is best. Protein quality of beans, bread rolls, soy, pasta and dairy products is worst.
In Detail :
The proteins you consume are composed of amino acids. But if these proteins lack 1 of the essential amino acids, you can't use them for construction purposes. So we don't need protein, but amino acids.
Like 10+ days mother's milk, fruit as an average contains only 1% protein. And just as babies obtain all required protein from human milk, adults can obtain all required protein from fruits.
Even consuming the right mixed fruits only, you will absorb almost twice as much of all the amino acids as you minimally need°. Simply because you need to consume lots of fruit to obtain sufficient calories.
Consuming the right fruits, you will absorb too little energy from it before you will absorb too little protein. Absorbing sufficient energy from fruits comes with absorbing sufficient protein.
° A lean 60kg woman for example, needs to consume 2 to 4 kg of fruit to obtain sufficient calories. (2000 to 3600 kcal)
A lean 80kg man for example, needs to consume 4 to 6 kg of fruit to obtain sufficient calories. (3600 to 5300 kcal)
Mixed fruit (equal portions of pineapple, banana, orange, mandarin, peach and avocado, and 100g of dried figs , 100g dried date + 35 g brazil nuts), contains (in mg) more of every amino acid (1) than we need ;
Fruits however, do not contain vitamin B12, vitamin D nor cholesterol. And besides fruit, everybody wants to eat some potato crisps or other munch-food, containing 'bad' protein. Therefore you also need a little animal food every once and a while, containing vitamin B12, -D, cholesterol and much more of all the essential amino acids too.
Consuming natural foods (fruits and some raw animal food), you will always absorb more than sufficient protein. Therefore, the body cannot even store protein. Sugars and fats are more scarce (and more short-term essential), and can therefore be stored as glycogen, glycerol and fatty acids.
How could we ever believe we need much protein ?
Protein quality of some fruits ;
91% Brazil nut
30% pineapple °
21% pear °
12% watermelon °
° Amino acid content not available in Souci, S.W. et al, Food Composition and Nutrition Tabels, Medpharm Scientific Publishers Stuttgart, and therefore obtained from the USDA Nutrient Database at www.nal.usda.gov/fnic/cgi-bin/nut_search.pl Using USDA amino acid tabels, Brazil nut-protein quality is 86%.
The Need For Protein
As infants grow older, they need less protein;
Pretransitional human milk (2nd to 3th day post partum) yet contains 2,6% protein.
Transitional human milk (6-10th day post partum) contains 1,6% protein.
Mother's milk (mature milk from 10th day post partum) contains only 1,1% protein.
Consuming more protein in general, does not at all enhance growth, for processing more protein requires extra vitamins and energy. Logically, Neanderthals consuming much more animal food ,were less tall than earlier Homo erectus, who consumed less animal food and more fruits.
Consuming lots of fruits and 50 gram of fresh raw salmon or -egg yolk daily, even tall men abundantly absorb all the protein they need.
Protein recommendations are much higher than protein requirements because ‘we are supposed’ to eat unnatural and prepared foods, containing badly composed protein.
* FAO / WHO recommendations are too high, for 'safety' reasons ; most food is consumed after preparation, causing destruction of amino acids. Compared to minimal need for amino acids, FAO / WHO recommendations are about twice as high as necessary. This has been affirmed through other scientific investigations ; To meet the minimal amino acid requirements, for each kg bodyweight, 0,60 gram (6) ,respectively 0,51 gram or 0,34 gram (7) potato protein appeared to be sufficient to maintain nitrogen balance. These figures equal 57%, respectively 48% and 32% of FAO / WHO recommendations for methionine and cysteine, the most scarce amino acids in potato protein, considering raw potato protein. In fact protein requirements are even lower, because in these investigations people were not fed raw- but prepared potato protein. And due to the preparation process protein quality decreases. In fried potato slices for example, protein quality has even decreased 70%. Considering a moderate 10% decrease, these potato protein intakes would meet 29% to 51% of FAO / WHO recommendations.
Prepared Proteinacous Food
People think protein is healthy, and fats and sugars are not. But that is not true ;
Due to the preparation of food, protein easily becomes mutagenic, toxic to the brain and / or mind altering. Damaged protein causes obesity, diabetes and stress. Sugars and fats are primarily essential to the brain and the heart. (see 13/brainfood)
Protein from prepared food is also not that valuable (anymore), because much essential amino acids are chemically altered due to the influence of heat. Protein quality of prepared pork for example, is 9 to 11% lower than protein quality of raw pork. (8) Frying potato slices (crisps) even decreases protein quality 70%, destroying almost all methionine. (9)
To compensate the low quality of proteins from unnatural- ,and from prepared food, a high total protein intake is officially recommended. Instead, to become much healthier, and to be able to focus much better, you should drastically reduce prepared protein- and unnatural foods consumption.
To absorb ample protein; all you need is fruits and a little high quality protein regularly.
Processing redundant protein requires extra vitamin B2, B6 and folic acid. That's why pregnant women that consume 'normal' (proteinous-) food can cause folic acid deficiency in their babies.
Also, by consuming more protein instead of little high-quality protein, the average protein quality decreases*.
Consuming the right fruits supplies you with all the protein you need. And if you think you need extra amino acids, you should consume high quality raw protein.
* Glutathione (also an antioxidant) is needed to absorb single amino acids (Meister cycle). And glutathion is partly (33%) composed of cysteine. The more single amino acids are absorbed, the more cysteine is required, whilst cysteine is (together with methionine) the most scarse amino acid in our food. The more protein is consumed, the worse average protein quality will be. An other reason to consume little ,but high quality protein.
Commonly, protein value is determined in comparison with chicken-egg-white-amino acid-content.
Yes, ... they say chicken-egg white-protein is the best, and therefore every deviating protein is less valuable. This however, is a lie;
Compared to the need of the human body for amino acids ,egg white-protein is not at all perfect. And therefore you can never judge proteins by comparing them to egg white-protein. Like you can't say that a student having lots of A's ,but a C for chemistry and biology, has perfect results, and that deviating results are worse per se. Suppose an other student has lots of A’s ,but a B for English and math, did he do worse ? Of course not !
To judge the students ,their results have to be compared to perfection, and not to non-perfect results of another student. Of course a B should be judged as a better result than a C. To judge food-proteins, amino acid contents have to be compared to the amino acid requirements of the body, not to a non-perfect food protein.
Chicken-egg-white protein is not at all perfect ; according to different scientific investigations, the adult human body needs 45% more (5) to 7% less (3) methionine and cystine than phenylalanine and tyrosine, but chicken-egg white protein contains 38% less methionine and cystine than phenylalanine and tyrosine. (10)
Logically, nobody agrees about how much of every amino acid we need. Logically, because the need for amino acids is different for each person, and also changes every day. But there is a very clear pattern ; consuming different foods, averagely, the amino acids methionine and cystine always are most scarce (compared to the need of the body). see weakest link at this page.
'A chain is as strong as its weakest link'. The same goes for proteins ; its quality is determined by the availability of the scarcest amino acids.
What do those figures below mean° ?
For example ; 1 gram of Brazil nut-protein supplies you with as much useful amino acids as 3 grams of milk protein does.
91% Brazil nuts (for external info, click here)
72% edible snail°°
62% chicken egg white°°°
56% horse meat°°
52% sole (fish)
49% ling (fish)
47% brown shrimp
46% oriental sesame
45% Horse mackerel (Jack mackerel)
45% rolled oats*
44% chicken egg yolk
43% mullet (fish)
42% crawfish (Spiny lobster)
43% cod (fish)
43% cashew nut
42% chicken breast / leg
42% pork, muscles only
39% soft clam
39% fruits menu***
39% wheat, whole grain
39% wheat whole meal bread
38% beef, muscles only
38% mutton, muscles only
37% turkey, young
37% cooked ham
37% veal, muscles only
37% rice, polished
37% wheat (flour) bread (white bread)
36% corned beef
36% quark, fresh cheese
35% sunflower seed
35% Edam cheese
35% maize, whole grain
35% Cheddar cheese
34% ewe's milk (sheep milk)
34% rice, unpolished
34% rye, whole grain
32% crisp bread
32% rye whole-meal bread
32% cow's milk, raw / reduced fat
31% almond, sweet
31% Parmesan cheese
31% Soya bean
31% winged bean (Goa bean)
30% lamb, muscles only
30% Brie cheese
30% pasta made w. eggs (noodles, spaghetti etc)
30% cow's milk, full fat / 3,5%
28% Soya flour
25% Mung bean (Indian bean, green- / golden g.)
24% Lima bean (butter bean)
22% potato (only 2% protein)
21% white beans
21% macadamia nuts
19% bread rolls
17% Cowpea, common
13% shredded wheat bread
13% Pigeon pea (Red gram)
10% Hemp seeds
8% Black gram (Mungo bean)
7% potato crisps
°Protein quality of every food has been calculated by relating the sum of cystine and methionine to 2 / 18 part of total protein content. The result reflects share of methionine and cystine in the particular food-protein, in comparison to the average amino acid share (there generally are 18 amino acids in food proteins). The list also shows that methionine and cystine are relatively scarce amino acids. Consuming different foods, averagely methionine absorption is always larger than cystine absorption.
°°In fact protein quality of horsemeat and edible snail is higher than stated, but the amount of cystine (and tryptophan in edible snail) is unknown. Consuming horsemeat does however decrease average availability of tryptophan for serotonin production ; consuming horsemeat can cause depressions / sleeplessness ; see site13.
°°°Raw chicken egg white contains avidine and ovomucoide, inhibiting digestion. Only consume raw egg yolk, containing most of all vitamins and minerals. (see site3)
*Rolled oats are the only cereals that can be digested raw relatively well (but you definitely don't need it !!!), buteven the rolled oats you find in the shops are not really raw, although they will tell you so. Raw rolled oats are hardly maintainable, and therefore always get some heat-treatment.
**Herring is always deep-frozen at sea, because raw herring can contain herring-worms.
***The fruits-menu is composed of 35 gram Brazil nuts, 300 gram orange, 300 gram banana, 200 gram avocado and 150 gram apricot (peach-amino acid cont.), for containing (together with some animal food) an ideal combination of vitamins and minerals.
The strength of a chain is determined by its weakest link. The quality of food protein is determined by the scarcest amino acid in total daily protein consumption.
Some people think it is determined each meal, but that is not true ; in the digestive tract endogenous protein (± 80 gram daily !!) is mixed with consumed proteins, eliminating the possibility that commonly-not-so-scarce amino acids incidentally can be most scarce. Also does the liver hold small amounts of amino acids, and fluctuate blood-amino acid levels, again eliminating incidental scarcities. Therefore the scarcest amino acid is determined by total daily protein consumption.
To determine the scarcest amino acid in relation to the need for amino acids, we first need to know how much of every (semi-) essential amino acid we need.
The official FAO / WHO 1985 recommendations include 'safety margins'. In milligrams / kg lean bodyweight ;
Amino acid requirements of, respectively ; adult men according to Rose in 1957 (3), of adult women according to Hegsted in 1963 (4), of 10- to 12 year old children according to Nakagawa in 1963 (11) and of suckling according to Snyderman in 1967 (2) ;
Minimal amino acid requirements, according to Rose (5) (plus total daily average requirements ; between brackets)
To determine the 'weakest link' we have to index amino acid requirements, to be able to compare these figures to indexed amino acid contents of foods.
What does this chart mean?
and the ones below?
Check out this page for an extended explanation.
Comparing the indexed amino acid requirements to the indexed amino acid contents of foods stated below, the general pattern is clear; methionine and cystine typically are most scarce in daily food.
For adults, methionine and cystine always are most scarce (100%). Even if only minimal amounts of amino acids are consumed, in 81% of foods methionine and cystine again are most scarce, in 19% tryptophan then is.
For schoolchildren, again methionine and cystine are most scarce in all foods except grains. In 47% of grains methionine and cystine are most scarce, but in 53% lysine is, depending on the applied amino acid requirements. However, nobody eats grains like bread and cornflakes only, again making methionine and cystine the scarcest amino acids in diets comprising lots of grains.
For younger children protein requirements match food-protein contents better, levelling relative availability ; in 57% methionine and cystine are most scarce. In 25% phenylalanine and tyrosine are, in 13% tryptophan is, and in 5% of foods isoleucine is most scarce, depending on the applied amino acid requirements. But, again, methionine and cystine are the scarcest amino acids.
All the scarcest amino acids possible, depending on applied amino acid requirements ; are printed in red when regarding adults, in yellow when regarding schoolchildren and underlined regarding younger children.
* In these foods, the amount of methionine is lower than the amount of cystine, making methionine the single most scarce amino acid.
Of course there also are 'exceptional' foods; logically, in high protein quality foods (see below) a variety of amino acids can be scarcest (29% tryptophan, 28% phenylalanine / tyrosine, 23% methionine / cystine, 12% threonine and 8% lysine)
But consuming these foods in combination with other foods doesn't change the fact that methionine and cystine averagely are most scarce.
In horse meat the amount of tyrosine is unknown, but in average meat phenylalanine / tyrosine ratio is about 1,11 / 1.
In edible snail the amount of tryptophan is unknown.
'Weakest Link' In Natural Foods
In natural raw foods, again methionine and cystine are most scarce.
Only if you consume no more than minimal amounts of amino acids, tryptophan can very incidentally be most scarce.
Protein Quality of Human Milk versus Formula Milk
(semi-) Essential Amino acid contents of human milk-, cow’s milk- and soy protein are related to the relative need for amino acids in suckling, below. Relative to the need for amino acids, in human milk phenylalanine appears to be the most scarce amino acid. In cow’s milk methionine and cystine are the limiting factor and in soy methionine solely is.
Subsequently, the obtained figures are indexed to the most scarce amino acids, as stated in “relative amino acid requirements in suckling” above. Because redundant methionine is transformed into cystine, in cow’s milk the average of methionine and cystine is equal to 58.
Next, the total of “relative amino acid requirements in suckling”, which is 897, is related to the total of all amino acids in each food. The surplus of amino acids in the listed foods can not be utilized for construction purposes, because lacking the most scarce amino acid(s). Finally, the obtained rates (63%, 50% and 61% respectively) have to be adjusted for the (semi-)essential amino acids / total protein ratio. Human milk-protein quality appears to be 35% better ((35-26)/26).
Amino Acid Contents
You can check amino acid contents in Souci, S.W. et al, Food Composition and Nutrition Tabels, Medpharm Scientific Publishers Stuttgart, or the USDA Nutrient Database.
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(1) Souci, S.W. et al, Food Composition and Nutrition Tabels, 5th ed. Medpharm Scientific Publishers Stuttgart 1994 / 804, 823, 873-877, 889, 909, 910 and 949. (dried-date-cystine content is taken from www.nal.usda.gov/fnic/cgi-bin/nut_search.pl)