Advice
Advice :: Nutrition :: Protein
Firstly one must understand that proteins are formed by the chemical bonding
(condensation) of amino-acids. Amino acids are the building blocks we require
to form the many different proteins within our body. The number, type and
ratio of amino acids within a sequence governs which protein is made. For
example, the contractile proteins actin and myocin found in human skeletal
muscle tissue have a specific ‘sequence' of amino acids. However this sequence
is very different to the amino acid sequence found in the fibrous protein
keratin, which is found in your hair. Again, this differs considerably from
the 191 amino acid sequence found in human growth hormone (somatotropin).
Besides building cells and repairing tissue, amino acids form antibodies
to combat invading bacteria & viruses, they are part of the enzyme & hormonal
system, they build nucleoproteins (RNA & DNA), they carry oxygen throughout
the body and participate in muscle activity. So, one can start to see if
we want to grow muscle, we must provide our bodys with the correct amino
acids that our found in our skeletal muscle tissue. There are a number of
articles which quote figures between 20 and 23 amino acids used by the body
to construct the many proteins we need. We can assure you that there is at
least 20 and they are named below. This might not be useful to every reader
but but some may have come across three-letter and single letter representations
for amino acids and wondered what they meant. Well here they are,
The Amino Acids
Name, Three-letter
code, Single-letter
code
Alanine, Ala, A
Arginine, Arg, R
Asparagine, Asn, N
Aspartic acid, Asp, D
Cysteine, Cys, C
Glutamic acid, Glu, E
Glutamine, Gln, Q
Glycine, Gly, G
Histidine, His, H
Isoleucine, Ile, I
Leucine, Leu, L
Lysine, Lys, K
Methionine, Met, M
Phenylalanine, Phe, F
Proline, Pro, P
Serine, Ser, S
Threonine, Thr, T
Tryptophan, Trp, W
Tyrosine, Tyr, Y
Valine, Val, V
Adults must include adequate amounts of 9 specific amino acids in their diet. These are called "essential" amino acids as they cannot be synthesised (made) from other precursors and so must be obtained from your food. However, cysteine can partially meet the need for methionine (they both contain sulfur), and tyrosine can partially substitute for phenylalanine.
The Essential Amino Acids
TRYPTOPHAN
A natural relaxant, helps alleviate insomnia
by inducing normal sleep, reduces anxiety & depression, helps in the treatment
of migraine headaches, helps the immune system, helps reduce the risk of artery & heart
spasms, works with Lysine in reducing cholesterol levels.
LYSINE
Insures the adequate absorption of calcium, helps
form collagen (which makes up bone cartilage & connective tissues), aids
in the production of antibodies, hormones & enzymes. Recent studies have
shown that Lysine may be effective against herpes by improving the balance
of nutrients that reduce viral growth. A deficiency may result in tiredness,
inability to concentrate, irritability, bloodshot eyes, retarded growth,
hair loss, anaemia & reproductive problems.
METHIONINE
Is a principle supplier of sulfur which prevents
disorders of the hair, skin and nails, helps lower cholesterol levels by
increasing the liver's production of lecithin, reduces liver fat and protects
the kidneys, a natural chelating agent for heavy metals, regulates the formation
of ammonia and creates ammonia-free urine which reduces bladder irritation,
influences hair follicles and promotes hair growth.
PHENYLALAINE
Used by the brain to produce Norepinephrine
(noradrenalin), a chemical that transmits signals between nerve cells and
the brain, keeps you awake & alert,
reduces hunger pains, functions as an antidepressant and helps improve memory.
THREONINE
Is an important constituent of collagen, elastin,
and enamel protein, helps prevents fat build-up in the liver, helps the digestive
and intestinal tracts function more smoothly, assists metabolism and assimilation.
VALINE
Promotes mental vigour, muscle coordination and calm emotions. This amino
acid is one of the BCAA's (See later).
LEUCINE & ISOLEUCINE
They provide ingredients for the manufacturing of other essential biochemical
components in the body, some of which are utilised for the production of
energy, stimulants to the upper brain and helping you to be more alert. These
two amino acids make up the other BCAA's.
HISTIDINE
Is found abundantly in haemoglobin, has been used
in the treatment of rheumatoid arthritis, allergic diseases, ulcers & anaemia.
A deficiency can cause poor hearing. We have added Histidine in for completeness,
as some say this is not considered to be an essential amino acid.
Two of the essential amino acids, lysine and tryptophan , are poorly represented in most plant proteins. Thus strict vegetarians should ensure that their diet contains sufficient amounts of these two amino acids.
When protein from food is broken down by digestion the result is amino acids. As said, nine are “essential” the rest are non-essential and make up the remaining amino acids used. These non-essential AA's are listed below,
Non-Essential Amino Acids
ARGININE
Studies have shown that is has improved immune
responses to bacteria, viruses & tumour
cells, promotes wound healing and regeneration of the liver, causes the release
of growth hormones, considered crucial for optimal muscle growth and tissue
repair.
TYROSINE
Transmits nerve impulses to the brain, helps overcome
depression, Improves memory, increases mental alertness, promotes the healthy
functioning of the thyroid, adrenal and pituitary glands.
GLYCINE
Helps trigger the release of oxygen to the energy
requiring cell-making process, Important in the manufacturing of hormones
responsible for a strong immune system.
SERINE
A storage source of glucose by the liver and muscles,
helps strengthen the immune system by providing antibodies, synthesises fatty
acid sheath around nerve fibres.
GLUTAMIC ACID
Considered to be nature's "Brain
food" by improving mental capacities,
helps speed the healing of ulcers, gives a "lift" from fatigue,
helps control alcoholism, schizophrenia and the craving for sugar. Glutamic
Acid is a precursor to Glutamine and GABA. Excesses Glutamic acid in brain
tissue can cause cell damage. This is thought to be one of the mechanisms
by which strokes kill brain cells, that is through the release of large amounts
of Glutamic Acid. Also worth a mention is the fact that it detoxifies ammonia
in the brain by forming glutamine, which can cross the blood-brain barrier,
which Glutamic Acid cannot do.
GLUTAMINE
A huge 60% of your skeletal muscle is Glutamine
and so Glutamine has the highest blood concentration of all the amino acids.
Glutamine is the precursor to the neurotransmitters GABA and Glutamate (Glutamic
Acid). This is a vital function, as GABA is an inhibitory neurotransmitter
that produces serenity and relaxation. Glutamine is an important glycogenic
(“generates glucose”)
amino acid, meaning that it is essential for helping maintain normal and
steady blood sugar levels. It is also an anabolic and anti-catabloic amino
acid which is obviously very useful properties when trying to build new muscle.
Glutamine is essential for gastrointestinal function as it provides energy
to the small intestines. The intestines are the only organ in the body that
uses Glutamine as its primary source of energy. Look for L-Glutamine which
is the body's preferred form. The other form is D-Glutamine, the L (Levo
= left) and D (Dextro = right) notation is used by chemists who use light
to differentiate the two forms (enantiomers). This notation is used widely
within the food and drug industry. Most drugs are made as a 50:50 mix (racemic
D,L mixture) and must be separated as some forms of a drug can be toxic to
the body.
ASPARTIC ACID
Aids in the expulsion of
harmful ammonia from the body. When ammonia enters the circulatory system
it acts as a highly toxic substance which can be harmful to the central nervous
system. Recent studies have shown that Aspartic Acid may increase resistance
to fatigue and increase endurance.
TAURINE
Helps stabilise the excitability of membranes which
is very important in the control of epileptic seizures. Taurine and sulfur
are considered to be factors necessary for the control of many biochemical
changes that take place in the aging process, aids in the clearing of free
radical wastes.
CYSTINE
Functions as an antioxidant and is a powerful aid
to the body in protecting against radiation and pollution. It can help slow
down the aging process, deactivate free radicals, neutralise toxins, aids
in protein synthesis and presents cellular change. It is necessary for the
formation of the skin, which aids in the recovery from burns and surgical
operations. Hair and skin are made up 10-14% Cystine.
PROLINE
Is extremely important for the proper functioning
of joints and tendons, also helps maintain and strengthen heart muscles.
ALANINE
Is an important source of energy for muscle tissue, the brain and central
nervous system, strengthens the immune system by producing antibodies, helps
in the metabolism of sugars and organic acids.
Branch-Chain Amino Acids (BCAA)
Branched Chain Amino acids
comprise an Estimated 35% of Muscle Tissue. The term BCAA refers to the amino
acids L-Leucine, L-Isoleucine, and L-Valine. Its their particular molecular
structure that gives them their name (branched chain amino acids). The BCAA's,
particularly L-Leucine, help increase work capacity by stimulating the anabolism
and prevent muscle breakdown during exercise. BCAAs are needed for the maintenance
of muscle tissue and appear to preserve muscle stores of glycogen. BCAA's
are also essential amino acids.
Protein Assessment
So how do we measure protein quality?
There are a number of methods used and they are listed below. Please note
that depending on which method you choose, you may find the answer to the
question “which protein source is
best” will differ.
Amino Acid Score (A.A.S)
This method simply evaluates quality
as a comparison of amino acid composition to a reference protein.
Biological Value (B.V)
This is a common method used to
evaluate the amount of protein kept by the body as absorbed nitrogen. The
B.V. of some foods are listed below:
Protein B.V
Whey Isolates 110-159
Whey Concentrates 104
Casein 77
Soy 74
Whole Egg 100
Cow Milk 91
Albumin (Egg White) 88
Fish 83
Beef 80
Chicken 79
Wheat 54
Beans 49
Net Protein Utilisation (N.P.U)
Simply a measure of retained nitrogen from your food.
Protein Efficiency Ratio (P.E.R)
This ratio is basically a comparison of weight gain to protein intake.
Protein Digestibility Corrected Amino Acid Score (PDCAAS)
Bit of a mouthful but this method compares the amino acid score of food
protein with the amino acid requirements of pre-school kids and is then corrected
for what is required for true digestibility.
So that covers amino acids. We will move on to protein supplements. From what was said above one can start to appreciate that the best protein powders on the market should reflect, in composition, what our muscles are made up of (listed at the very end of this section). There is a hierarchy of amino acids and in our muscles and 60% is glutamine, which is why the biggest portion of your protein will (or should) contain glutamine, or glutamic acid and then descend down the hierarchy. Obviously, a real easy way to ensure you have all the correct amino acids in the exact amounts we require to build our muscles is to eat another human's muscles! This is somewhat unethical (unless your surname is Lecter) and so we advise you to stick to protein powders and basic foodstuffs!
Other terms one might come across are Whey Isolate, Whey Concentrate, Soy Protein and Micellar Caseinated Protein. After you read the following paragraphs we hope you will be in a more informed position and will be able to decide more confidently what protein is best for you to meet your requirements.
Firstly, it is recommended when training to gain muscle to have anywhere from 1 - 3 grams of protein per lb of body weight on a daily basis, depending on your physical goals and requirements. However, your body can only ‘absorb' (assimilate) a certain amount of protein at any one time. The rest is excreted and urea (waste product) levels can get high, hence why we need to drink a good amount of water and also need to replenish protein supplies frequently with good protein sources at each meal; this way there is always a steady supply of amino's available for the body to use in growth/repair cycles. We do not store protein like other nutrients, the body happily stores up fat and carbohydrates in our bodies for such times as there is a calorie deficit.
So what about the protein we consume? Well make no mistake about it, that 150g chicken breast you just ate by no means supplies your body with 150g of useful protein. Chicken is good for building Chickens, Steak for building Cows and Tuna for building Tuna. As said above, only by eating other humans can we be sure of getting the correct protein in one serving. That is why we must mix our protein sources to ensure the correct abundance of all amino acids we require. The closest food to our own protein profile is a whole egg. You may find the following paragraph useful, it was taken from a friends website at www.extremenutrition.co.uk
“You may look at your protein powder or can of tuna and read that it contains "75% Protein", this may well be the case but if that protein only has 14 out of the 22 Amino Acids present in the human body, it means our highly resourceful body must manufacture the missing aminos from the ones we have ingested. The problem being, it is done so at the expense of these already eaten aminos. So that 50 gram serving of tuna gave you 32.5 grams of protein, but it only had 14 amino acids present, so by the time your body has chopped and rebuilt the aminos you supplied it with back into the aminos we really need, you've only ended up with about 20 grams of relevantly proportioned protein making it through to the bloodstream, which in turn takes it to your muscles.”
Common Protein Supplements
Whey Protein Concentrate & Whey Protein Isolate
Firstly
you may like to know that the bucket of whey protein you just bough is the
waste by-product of cheese manufacture! The milk is curdled, separating the “curd” from
the “whey”. Today's concentrates now contain up to 70%-80%
protein, with greatly reduced amounts of lactose and fat compared to the
amounts they first contained. Many people are under the impression that a
whey protein concentrate is inferior to a whey protein isolate. We do not,
and will explain as follows.
Although concentrates will contain less protein on a gram for gram basis than an isolate, a high quality concentrate contains all sorts of interesting compounds not found in the isolates. Good concentrates contain far higher levels of growth factors, such as IGF-1, TGF-ß1, and TGF-ß2. They contain much higher levels of various phospho-lipids, and various bio-active lipids, such as Conjugated Linoleic Acid (CLA), and they often contain higher levels of immunoglobins and lactoferrin.
Although scientific evidence is lacking as to whether or not these compounds found in a good quality concentrate will positively effect an athlete's muscle mass or performance, studies do suggest these compounds can improve immunity, intestinal health, and have many other effects that the whole population would find beneficial, not only athletes.
The downsides of concentrate is that it has slightly less protein gram for gram than an isolate, lower B.V and contains higher levels of fat (though some of these fats may in fact be beneficial), worst of all higher levels of lactose. Lactose is a common source of allergy for at least 20% of our population.
Isolates can contain as much as 90%+ of protein. Research has found that only whey proteins in their natural state have biological activity. The necessary amount of processing carried out upon a whey protein to remove the lactose, fats, etc. without losing its biological activity takes special care by the manufacturer, and incurs the relevant financial penalty that accompanies this level of work. Maintaining the natural state of the protein is essential to its anti-cancer and immune stimulating activity, the protein must be processed at low temperatures if it is not to alter the natural state of the protein (So we hope you start to appreciate how much value for money your receiving when you purchase our specially selected, highly refined protein brands from our shop!).
These processes include micro filtering, cross flow filtration and ion exchange. These filtration methods create isolated protein, but at the same time they take away some good compounds found in a good concentrate and can also reduce the number of amino acids present in isolate compared to concentrate. However, isolates do contain good amounts of BCAA and aid in the production of Glutathione, a natural anti-oxidant. Therefore it becomes a matter of choice and your choice should reflect your needs. We would prefer to have a concentrate included in our protein and get the added benefits that it brings rather than go for the lower fats and miss out on any amino acids. So we recommend a protein product that contains both concentrates and isolates, but again, it depends on your individual needs.
Providing your carbohydrates are under control, then a little extra fat shouldn't be a big concern. If you're training hard (but still below your aerobic threshold) you'll burn the extra fats no problem. When it comes to cutting up for a competition or an event where you need to be really lean, we advise you swap to a multi protein source product which would have less fat and an enhanced amino acid content.
Micellar Caseinated Protein
Casein is the curd portion of the whey making process. It contains high
amounts of glutamine but low amounts of BCAA's compared to whey and soy.
Sadly it naturally contains lactose and doesn't blend well. It is still a
great protein source as casein based proteins prolong digestion and absorption
which has been shown to have an increased anti-catabolic effect.
Soy Protein
This protein source is neglected by comparison
to the others, except for members of the vegan community. This is a shame
as soy protein is a very respectable protein source. There has been a lot
of new interest in soy (see our GeniSoy range) as it has been found to have
many health promoting effects. See the “Soya Protein and Health” section
in our GeniSoy range for detailed information. Suffice to say here that the
new soy isolates may enhance production of thyroxin, lower cholesterol, increase
bone density, reduce risk of hear disease and improve breast and prostate
health. These new isolates also score highest in the PDCAAS.
Protein Per Serving, How much is safe?
There has been much debate on how much protein we can safely digest in one
serving or meal. Supplement companies all recommend different serving sizes
for their products and most references seem to refer to a study done in the
1970's on subjects with pre-existing health problems. This study done nothing
but show how a high protein diet put additional strain on the subjects kidneys
and renal system. The UK Food Standards Agency state as a guideline on their
website,
"The daily recommendation for adults (over the age of 19) is 55 g protein per day. But it's the balance of foods we eat over a few days that's important, rather than what we eat every day. So if you don't manage to eat much protein on one day, you should aim to eat a bit more over the next few days. This is because the body contains a small reserve of protein so it can cope with day-to-day variations. However, eating large amounts of protein is bad for the kidneys, so it's important not to eat too much protein, and it's especially important to keep within twice the recommended amount."
They do not support any of the above with any evidence.
The American Heart Association (AHA) stated in 2001:
"Individuals who follow these (high protein) diets are risk for potential cardiac, renal, bone and liver abnormalities overall. "
This alarming statement must cause concern to the general public and in turn deter many people from following an Atkins type high protein diet plan which incorporates a reduction in carbohydrate intake.
The justification of such a statement is unclear as there is no scientific evidence that high protein intake has adverse effects on liver function. Also, there is no scientific documentation to support the theory that healthy kidneys are damaged by the increased demands of protein consumed at 2 - 3 times the Recommended Daily Allowance (RDA). A study by Portman Dellalieux investigated bodybuilders and other highly trained athletes with medium to high protein intakes. The athletes underwent a 7 day nutrition record analysis as well as blood sample and urine collection to determine the potential consequences of such a diet. The subsequent data showed despite higher uric acid and calcium, the athletes had renal clearances of creatinine, urea and albumin which were all considered to be within a normal range. This admittedly short study was done with protein consumption of up to 2.8g/kg of body weight i.e. 3.5 times as much as the recommended daily allowance.
In contrast to the theory that a high protein diet promotes osteoporosis, there has been some epidemiological studies showing a positive effect of protein intake and bone mineral density.
Dr. Eric L. Knight, from Massachusetts General Hospital in Boston concluded after studying the effects of protein consumption vs kidney function that,
"Based on this study, I would say in individuals with normal kidney function, we have no reason to believe that a relatively high protein intake has a harmful effect on the kidneys."
The findings appear in the March 2003 issue of the Annals of Internal Medicine.
The following chart is recommended by the Australian Institute of Sport,
Protein Requirements of Different Athlete Groups
Type of Athlete g protein/kg.BM/day
Sedentary individual 0.8
Athlete undertaking general training program
1.0
Endurance athlete undertaking moderate/heavy training 1.2 - 1.6
Endurance athlete
undertaking extreme training program 2.0
Strength athlete undertaking heavy
training program 1.2 - 1.7
Adolescent Athletes 2.0
So what does this really mean to people concerned with increasing muscularity or wanting to maintain a protein based diet to control fat levels or those involved in an intense exercise program which stresses skeletal muscle? I think it shows that anecdotal evidence relating to high protein intakes doesn't relate to the people who are most likely to be consuming the most protein, because almost all studies are done on people with medical problems in which a high protein intake may effect them negatively. The studies we have mentioned were done on healthy individuals who regularly exercised and the most important fact to take away was that they found no problems with their health. Once more definitive proof has been established as to weather or not a (prolonged) very high protein diet has adverse effects of renal function, we will report it here. But for now, we are confident to say that providing you are healthy, you are not at risk of damaging your liver or kindneys by eating lots of protein.
We hope this conveys to you that the old 30g - 40g of protein per serving theory is not only out dated but also incorrect, this figure was a conclusion drawn by an American study done in the 1970's on recovering alcoholics who were suffering from a degree of liver and renal failure! It was found that servings of over 30g protein at any one time was not fully digested and caused stress to the subjects renal system as the demands put on the kidneys to process the additional nitrogen (and elevated urea) were increased.
Did Arnold Schwarzenegger build such a physique on 6 meals a day containing 30g of protein? We think not!
As individuals with differing numbers of muscle fibres and muscle density, we can all digest differing amounts of protein, that's a fact! This physiological factor coupled with the demands we all put on our bodies both mentally and physically has an effect on our ability to digest protein. We can work out exactly how much protein is being used by our muscle fibres for growth and repair. We can do this by working out our Protein Turn Over Rate (PTOR). We will come back to this shortly. It is worth saying simply that until a study is done on people who are pushing the boundaries of protein consumption, we must do what we feel to be right for ourselves, and follow what seems to allow us to recover from our chosen form of exercise swiftly and allow those of us who want added muscle tissue to still have enough excess protein in our diet to support this new tissue growth.
The body has a hormone controlled balance between anabolisim (muscle making) and catabolism (muscle degradation), this balance has a fancy name called homeostasis. This protein making and breaking process by muscle groups is called the PTOR. The body has a base PTOR of body weight (in lbs) multiplied by a factor of 1.818. So a 200lb person would have a PTOR of 200 x 1.818 = 363.6g. However, different muscle groups have different PTOR and so muscles grow and shrink and different rates. The rate is governed by a number of factors including circulating nutrient and hormone supply, the number and nature of receptor sites on the cell surface and the type of stress through training placed on the muscle. So why is this important? Well the PTOR will favour catabolism when dietary protein consumption fails to provide adequate amounts and correct ratio's of amino acids. So if you want to stay at your maximum anabolic level then you will have to at least consume your body's base PTOR in protein daily (remembering that the correct ratio's of amino acids must be met). You may have come across the general rule “take at least 2g per lb body weight”? Well this is good, as it is easier to remember 2 than 1.818 and this marginal increase will provide roughly 35g surplus protein which is available for your body to use. From the example above, the 200lb person has a PTOR of 363.6g. If they used 2g/lb this would become 400g giving a difference of 36.4g protein excess which if the body is in an anabolic environment could be used for new muscle growth. If the person was on 4g/lb body weight they would be consuming 800g protein per day giving 436.4g surplus available to the body to construct tissue (although even the most genetically blest wont be able to build new muscle at that rate per day, every day!)
How much protein should I take?
We advise that you work out your base PTOR and consume at least this amount if you wish to improve your physique. Remember you must mix protein sources to ensure correct amino acid quantities are met. We suggest you take half from drinks and half from sources including red meat, fish, eggs and low fat dairy products. If your intention is to gain a lot of muscle then we advocate quantities of 2g-4g per pound of body weight on a daily basis. Remember you get 4 calories per gram protein so if you have a calorie target diet then you will have to work out exactly how many calories are coming from protein. For example if you are on a mass gaining diet of 7000 calories, weigh 220 lbs and are taking 4g/lb body weight then total calories from protein are 220lb x 4g/lb x 4cal/g = 3520 calories, leaving the rest to come from carbohydrates and fats. Lastly, if you were having six meals per day then you would be looking to eat around 147g of protein per meal (880g/6 meals) but remember you would want to consume a larger protein portion post workout than any other meal of the day.
Amino Acid Profile For Human Muscle Growth Requirement
Amino Acid % Required
Alanine 2.5
Arginine 9.0
Aspartic acid 2.0
Asparagine 5.5
Cysteine 0.5
Glutamic acid 10.0
Glutamine 10.0
Glycine 3.5
Histidine 2.0
Isoleucine 6.0
Leucine 9.0
Lysine 10.0
Methionine 5.0
Phenylalanine 2.5
Proline 2.0
Serine 5.0
Threonine 4.0
Tryptophan 3.0
Tyrosine 2.5
Taurine 1.0
Valine 5.0
Take a look at the label on your protein tub and see how it compares? This is a close reflection to what our skeletal muscle composition actually consists of. We hope now that when your shopping for your next tub of protein, you will know exactly what you want from it. For example, are you looking for pure isolates, a blend of isolates and concentrates, soy, a high BV protein, low lactose and sugars, slow absorption, easy mixing and good tasting or one that is high in L-Glutamine and BCAA? There are many protein blends from many manufacturers available so if you want the best protein for you, do your homework and only buy high quality manufactured blends from reputable companies, like we do! Happy shopping!