Y O R K m i n d - b o d y H E A LT H
www.yorknutritionaltherapy.co.uk 01904 435 267 Glyn Blackett
What Is Protein? Protein and the Diet
About half the dry weight of your body is
We obtain our amino acid building blocks, from
protein. There are thousands of different kinds of which our cells build our proteins, from dietaryprotein molecules, performing a variety of
protein. Plants and animals like us are built from
functions. Most protein is structural – it makes
protein. We don’t use dietary protein molecules
up skin, hair, bone and teeth. Enzymes –
directly - rather they are broken down in the
molecules which drive chemical reactions in the
process of digestion into the constituent amino
body – are mostly proteins. Other examples are:
Haemoglobin – found in red blood cells, it is
Actually the body can make several amino acids
vital for transporting oxygen to cells.
from others, but eight of the twenty-two are
Insulin – a hormone or signalling molecule.
essential, meaning they can’t be made and mustbe obtained from the diet. Several more amino
Protein and Amino Acids
acids are semi-essential meaning they can’t be
A protein molecule is made up of a sequence of
basic building blocks called amino acids, joined
Fully meeting the body’s protein needs requires
end to end. (The chemical bonds between aminoacids are called peptide bonds.) Protein
i You eat adequate amounts of the amino acids,
molecules differ in terms of the number of
ii Your body can successfully break down the
specific sequence. Most proteins are able to
protein you eat and absorb the amino acids
serve their particular purpose by virtue of the 3D
shape of the molecule, which is likewise a
function of the specific number and sequence ofamino acids. Protein and Digestion
There are 22 amino acids found in nature. All
The breaking down of proteins into amino acids
happens largely by the action of stomach acid, inthe presence of particular enzymes called
Proteins and Genes
proteases. If you don’t produce enough of these,
Your body manufactures proteins to order. The
blueprints for proteins are found in the genes.
compromised. Stomach acid insufficiency, a
That’s essentially what a gene is - a blueprint for condition known as hypochlorhydria, isone or more protein molecules. If the
relatively common. Stomach acid production
manufacturing process goes wrong, the result is
naturally declines as we age. Furthermore, many
often a protein with the wrong sequence of
people take acid suppressing medications.
amino acids. Because these faulty molecules
Conversely true cases of stomach acid excess are
form unexpected 3D shapes, they can’t perform
rare - often what is perceived as an excess of
their intended functions. In the genetic disease
acid is actually an inability of the stomach lining
sickle-cell anaemia, haemoglobin molecules turn to withstand its own acid - a problem with theout wrong in just this way, with the consequence stomach lining not the acid. Alternatively if thethat the blood cannot transport oxygen in the
acid gets to places where it shouldn’t (notably
the oesophagus) it is treated as excess acid. Protein Sources Protein – Carbohydrate Balance
Dietary protein comes from both plant and
Another important function of dietary protein is
that it slows the absorption of sugar into the
Animal: meats, fish, eggs, diary products
blood, which can cause problems if it’s too fast.
Balanced, stable blood sugar levels are importantfor mood and energy stability. Therefore a useful
Plant: beans and pulses, nuts, whole grains,
principle is to have a protein component for
seeds (fruit and vegetables contain negligible
every meal. This has the benefit of being more
Breakfast is for many people is protein-light –
As stated, we need the full range of amino acids
although milk is a source of good quality protein
in the right proportions – especially the eight
it doesn't have large amounts (as it's a liquid).
essential amino acids. This idea is quantified as
An egg at breakfast time is a good way to get
the Biological Value (BV) of a protein source - a your protein. high value source has all the essential amino
Snacks are also commonly lacking in protein.
acids in the right proportions. It turns out that
Ideal snacks are nuts and seeds, which have a
animal sources in general have higher BV. Many variety of healthy nutrients besides protein. Oat
plant sources such as brown rice, are missing
cakes with cottage cheese, tinned fish or
one or more of the essential amino acids.
hummus also make easy snacks or even light
However, soya beans and quinoa do contain all
eight (they are known as complete proteins). Note that eating large amounts of animal foods
Protein as Energy
is probably not healthy for other reasons, so
Protein is not just used structurally by the body,
plant sources, which have other health-giving
it can also be burned to release energy. Whilst
properties besides, should not be neglected.
this is a natural process happening to some
Here are some BV scores of some typical high
extent all the time, in conditions of starvation,
protein can become the major source of energy. Muscle wastage is the result of the bodymetabolising its own protein for energy. This isone reason why semi-starvation diets are a badidea - some of the weight loss is not fat loss butmuscle loss.
Evidence suggests that different people’smetabolisms are tuned to burn carbohydrates andproteins with more or less efficiency. Thepractical consequence is that some people willdo much better on a diet relatively high inprotein, while others a relatively low protein dietserves them best. This idea is behind the conceptof metabolic typing, covered in a separatearticle. How Much Protein Do We Need?
Estimates vary. The World Health Organisationsuggests around 10% of your total calorie intakeshould come from protein, or around 35g a day. The UK Department of Health suggests 36g forwomen and 44g for men. Some weight loss dietssuggest much higher amounts.
Too much protein is not a good idea. It can cause amino acid called tryptophan. In one study,osteoporosis and can put excessive strain on the
subjects who ate a diet devoid of tryptophan
kidneys. Modern farming methods mean that
developed symptoms of depression (2). Thus we
many animal sources of protein contain high
can conclude that adequate protein in our diet is
levels of hormones such as oestrogen. Contary to important for mental and emotional functioning. popular opinion, you don’t need high levels or
protein to build muscle mass, even if you are a
1. Source: 'The Insulin Factor' by Antony
The right level is really an individual matter - it
2. This study was published in the Lancet in 1997.
depends on your individual biochemistry.
(Smith, K. et al. 1997 ‘Relapse of depression afterrapid depletion of trypophan’ Lancet Vol.349
Amino Acids and Neurotransmitters
Neurotransmitters are molecules that transmitsignals between nerve cells, and as such are avital aspect of brain functioning. Examples ofneurotransmitters are serotonin and dopamine. Itis thought that neurotransmitter imbalance playsa role in mood disorders such as depression, andcognitive disorders such as ADHD. Neurotransmitters are either amino acidsthemselves or are derived biochemically fromthem. Serotonin for instance is derived from an
Hepatite aguda por Dengue CASE REPORT ACUTE HEPATITIS DUE TO DENGUE VIRUS IN A CHRONIC HEPATITIS PATIENT Souza L.J1, Coelho J.M.C.O.4, Silva E.J. 2, 5, Abukater M.1, 2, Almeida F.C.R.1, 2, Fonte A. S.1, 2, Souza L.A. 1,3 1Centro de Referência da Dengue/Hospital Plantadores de Cana – Campos dos Goytacazes – RJ; 2Faculdade de Medicina de Campos; 3Universidade Estácio de Sá;
2005-08-29 - 2005 08-31 Dubbla diagnoser – Dubbla möjligheter, Åre 2005-08-29—31________________3 Invigning med Elsa Danielsson, kommunalstyrelsen i Åre___________________3 Missbruk och psykisk problematik hänger ofta ihop Björn Fries Narkotikasamordnare, MOB, Anders Milton Psykiatrisamordnare __________4 Frågor från publiken:__________________________________