Nutritional Science takes into account anatomy & physiology and biochemistry. In order to really understand Nutrition, you need to look beyond the food - what happens down at cellular level- where the real work is done!
Digest, Absorb and Metabolise - how we get our energy from food
You have most likely heard the saying "you are what you eat". Whilst this has some merit of truth, we should look more at "you are what you digest, absorb and metabolise".
You can eat very healthy foods however, if you are not digesting the food into smaller, absorbable units, the you won't be fully using the food for energy, growth & repair.
The process of digestion begins in the mouth with carbohydrates and lipids, ends in the upper part of the small intestine, with protein digestion beginning in the stomach.
Other organs and glands are also involved along the way.
Non digested and absorbed foods pass into the large intestine. These can be further broken down by gut microbiota. Anything not used, passes out of the body as faeces.
There are two types of digestion : mechanical and chemical.
Mechanical digestion involves chewing your food (mastication), churning in the stomach and movement of the smooth muscles along the way. The chemical structure does not change but physical structure, does. By breaking the food into small sizes, it allows the process of chemical digestion to perform at an optimal level.
Chemical digestion predominantly involves special proteins called enzymes. These are very specific to components in food eg. carbohydrate A = carbohydrate enzyme A; Protein A = protein enzyme A and so on. This is some times referred to as the "lock & key" process. Enzymes are referred to as catalysts, they speed up the process without themselves, being destroyed.
Chemical digestion also involves factors such as HCL (hydrochloric acid) & bile acids.
The majority of digestion occurs in the small intestine. If the digestive processes in the mouth and stomach have done their job, then the SI enzymes can do their job to further reduce the foodstuffs (substrate) .
Examples of enzymes include: mouth - salivary amylase (starchy carbohydrates/ polysaccharides); stomach - pepsin (large proteins) ; small intestine - trypsinogen (smaller proteins), pancreatic lipase (fats & oils), pancreatic lactase (lactose from milk & soft cheeses), pancreatic maltase (maltose from breads & cereals). And many more....
The aim is to reduce foodstuffs into their smallest unit - proteins into amino acids; lipids into fatty acids & glycerol, and carbohydrates into their smallest units of glucose, galactose & fructose.
These units can then pass into the cell membrane and through to the blood stream (absorption) where they can then be used (metabolised) to become new proteins, new lipids and used as fuel. Any parts not digested eg. fibre, move on to the large intestine.
Issues can arise with digestion if you have insufficient or no enzymes and/or too much substrate. Undigested and partially digested foodstuffs can pass into the large intestine causing gas, bloating, pain and cycles of diarrhea/constipation. Large proteins may also pass into the bloodstream from the small intestine, causing "leaky gut syndrome" and potentially set up an over reactive immune response. So remember to chew!
This is a very simplified version of what happens (or it becomes a lecture!) but to summarise, what you put in your mouth and how you and your body deal with it, will affect what happens on the inside and what comes out the other end!
I think this is enough to digest & absorb for now......
Watching your blood pressure - reduce this pressure!
Let's start with the circulatory system-
Heart
Blood Vessels :
Arteries, Arterioles
Veins, Venules
Capillaries
Blood :
Erythrocytes /Red Blood Cells/RBC
Leucocytes /White Blood Cells/WBC
Thrombocytes /Platelets
Transported in Plasma
In addition :
The lungs
Cells, Tissues, Organs
What is blood pressure (BP)?
Blood pressure is the amount of blood your heart pumps and the amount of resistance to blood flow in your arteries.
The more blood your heart pumps and the narrower your arteries, the higher your blood pressure ie. HYPERtension. Therefore, the less blood pumped, the wider your arteries, the lower your blood pressure ie. HYPOtension.
There are two measures for overall blood pressure -
Systolic BP
pressure in the artery as the heart contracts.
the top, higher number.
Diastolic BP
pressure in the artery when the heart is relaxing and being filled with blood.
the bottom lower number.
Hypertension risks
Hypertension, or High Blood Pressure (HBP) is a common condition in which the long-term force of the blood against your artery walls is high enough that it may eventually cause health problems:
Damage to your arteries. Healthy arteries need to be flexible, strong and elastic.
Damage to your heart. High blood pressure can cause many problems for your heart walls, reducing or stopping ability to contract & relax.
Damage to your brain. Your brain depends on a nourishing blood supply to work properly. Without oxygen, your brain will suffer cell death. Nutrients are vital for brain functioning and hence, the rest of the body. You may suffer a cerebral infarction (stroke) and/or a TIA, transient Ischemic Attack (mini stroke)
Damage to your kidneys. Kidneys filter excess fluid and waste from your blood. This can lead to HBP, oedema and failure.
Damage to your eyes. Vision impairment. Due to lack of circulation in capillaries, starved of oxygen and nutrients.
Anaemia - the cellular level
When discussing the blood - a few terms
Erythrocyte - Red Blood Cell
Haemoglobin - iron-protein component of a red blood cell
NOTE: you will see anaemia and haemoglobin spelled with and without the "e" , both are the same word.
What is anaemia?
Anaemia is a lack of red blood cells or haemoglobin. Red blood cells and haemoglobin, the molecule in red blood cells that makes them red, are important because they carry oxygen from the lungs around the body.
It’s important to find and treat the cause of the anaemia as well as the anaemia itself.
B12 and Folate Anaemia - megaloblastic cells - large Red Blood Cells
What are the symptoms of anaemia?
Signs
What causes anaemia?
Anaemia is most commonly caused by iron deficiency, which can develop for several reasons:
If you are not eating enough foods that are rich in iron. Iron is important for the production of red blood cells. People who are following vegan and vegetarian diets may not get enough iron from their diet.
If you are unable to absorb iron from the foods you eat. Some health conditions affect how much iron you can absorb from your stomach and bowel, such as coeliac disease.
If you experience blood loss. Women are at increased risk of anaemia due to menstruation or heavy periods — 3 in 10 women of child-bearing age have anaemia. People with conditions such as Crohn’s disease, ulcerative colitis or stomach ulcers may also experience anaemia due to bleeding in the stomach or bowel. Regular blood donors are at risk of developing anaemia too.
If you have certain inherited or bone marrow diseases, including thalassaemia.
Sometimes anaemia is due to a lack of vitamin B12 — this is known as pernicious anaemia.
Insufficient intake of green leafy vegetables and/or fortifed cereals can cause folate related anaemia
Some chronic diseases such as chronic kidney disease and heart failure can also cause anaemia.
Some women develop anaemia during pregnancy due to their increasing need for iron throughout the pregnancy as well as heavy menstruation.
Coeliac Disease
Crohn’s Disease
Pregnancy
How are Iron, B12 and folate absorbed?
As well as ensuring sufficient iron, B12 and folate in the diet, how it is absorbed from the stomach (B12) and small intestine (iron, folate) to the cells is of vital importance.
Haeme (iron from animals) and Non-haeme foods (from plants) are absorbed slightly differently and affected by how well you digest foods containing these forms of iron, B12 involves the presence of a protein called Intrinsic factor to aid absorption.
(Fe - chemical symbol for iron from the Latin ferrum/ferrous; another form Ferritin*)
Haeme Iron and Non-haeme absorption
Non-haeme absorption
Cobalamin/B12 absorption and Intrinsic Factor
Absorption of B12 from stomach to liver to cells
The role of vitamins-B9/folate, B6 and B12 in methionine-metabolism-and-glutathione *
How is anaemia diagnosed?
A blood test for iron is usually performed to diagnose anaemia. If you have anaemia, your doctor will talk to you and examine you to work out how severe the anaemia is, and what the cause could be.
You might be asked to have more tests, depending on what your doctor has learnt from talking to you and examining you.
The little things - Viruses and Bacteria
They may be tiny and one isn't even considered a living thing but viruses and bacteria have a huge impact on all life on earth, not just humans.
They are part of the web of life, we need them to some extent. This is certainly the case for the majority of bacteria. However, in the wrong place, in large numbers and when there is no control, both became a major issue, illness and death.
What are Bacteria?
Bacteria are a collective group of microorganims that live almost every where - in the environment, in oceans, up trees, in and on our bodies. Singular - bacterium
They are Unicellular - one cell, have varying sizes and shapes and small living temperature zones. Most of useful/helpful however, a small percentage (~15%) are pathogenic and cause disease.
They divide by simple division and in optimal conditions for temperature, pH, oxygen presence or absence and light or dark conditions, can multiply quickly.
View how quickly bacteria can multiply - click on the link below
Our first encounter with bacteria is in-utero, then at birth and method of feeding ie. breast-feeding.
As we develop, we encounter more bacteria, from our external environment, new ones produced from our foods and contact with infected life forms and from surfaces. Whilst we need to be hygienic, we can negatively affect our bacterial balance by over use of sanitizers, sterilizers and antibiotics.
Types include:
Cocci round eg. Streptococcus pneumoniae; Staphylococci aureus
Bacilli rod eg. Bacillus cereus; Salmonella enterica
Spirilli spiral eg. Camphlobacter jejuni
Vibrio curved eg. Vibrio cholerae
Spirochaetes coiled eg. Borrelia burgorferi
Your Gut MicroBiome "good" and "bad"
Diseases caused by bacteria:
Cholera
Typhoid
Diptheria
Bacterial meningitis
Tetanus
Lyme disease
Syphillus and Gonorrhea
Sepsis
Conditions caused by bacteria:
Food poisoning
Salmonella sp, Listeria sp, Escherichia coli; Escherichia coli, Clostridium botulinum
Ulcers & gastritis
Helicobacter pylori
Bacterial Pneumonia
Streptococcus pneumonia
Skin related
Impetigo; boils; acne; cellulitis
"Strep" throat
Streptococcus sp.
Transmission:
Treatment for bacterial infections:
Whilst we need to maintain our "good" bacterial and in turn, our Immune System, there are times when "bad" bacteria (pathogenic) take over and can cause death.
General treatment is a course of antibiotics to bring them under control and allow our IS to fight the bacteria. There are vaccines for Tetanus, Cholera, Typhoid and Diphtheria.
"They aren't our bacteria, we are their humans"
(source unknown)
Reference sources- Image Bing search
What is a Virus? How can something so small be so dangerous!?
A Virus is a small sized infectious agent with a simple composition. Although tiny little things usually ranging from 0.02 to 0.3μm in size, they can cause a whole range of damage as we are seeing now with the Coronavirus (COVID-19) currently causing a pandemic and panic across the world. (news-med)
They are not plants, animals, or bacteria and should not even be considered organisms, as they are not free-living; i.e., they cannot reproduce and carry on metabolic processes without a host cell. Technically they are not alive! They can multiply only in the living cells of animals, plants, or bacteria. Viruses are parasites ie. they depend on the host cell for almost all of their life-sustaining functions. (news-med)
A virus is typically made up of a protective protein coat called a capsid which protects the viral genome from the external environment and plays a role in receptor recognition, enabling the virus to bind to susceptible hosts and cells. All true viruses contain nucleic acid—either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid)—and a protein. (news-med)
Viruses are not classified according to the illnesses they cause. They are grouped into different families based on whether 1. the nucleic acid is single- (RNA) or double-stranded (DNA), 2. whether a viral envelope is present and 3. their mode of replication.
DNA viruses tend to replicate within the nucleus of host cells, whereas RNA viruses generally do so in the cytoplasm. (news-med) Knowing where and how they reproduce is one of the keys to finding a vaccine, as well as prevention and treatment of the disease caused.
Stopping the virus before entering the body is the best scenario eg. good hygiene and quarantine, then supporting the immune system to recognise it before it enters the cell. Treatment to deal with the symptoms and best case scenario, prevent it replicating inside the cell.
The fact that a virus can sneak into the cell and “hide” is one of the main reasons why they can replicate without detection by the host organism’s immune system on first encounter. After replication, they virtually “explode” from one cell then infect the next until the whole organism is infected.
As a parasite, the virus doesn’t want to kill its host but depending upon the health and type of host, they can severely weaken and worst case scenario is that they do kill.
Whilst there are vaccines and antiviral medications available for a some types of viral infections, they are not always reliable as viruses have the ability to mutate. By the time a vaccine has been formulated, the original virus may have changed several times.
There are 4 main methods of transmission
Direct contact transmission: via physical contact between an infected and uninfected subject.
Indirect transmission: contact with contaminated objects or materials.
Common vehicle transmission: individuals pick up the virus from food and water supplies that are contaminated with faeces.
Airborne transmission :refers to the respiratory infection that occurs when the virus is inhaled. (news-med)
Worryingly, COVID-19 seems to be passed on 3 of the 4! Yet to hear of food and faecal.
There are 3 stages to creating new a new virus:
Replication of viruses involves primarily multiplication of the genome. It involves synthesis of viral messenger RNA (mRNA) from "early" genes then viral protein synthesis, assembly of viral proteins, then viral genome replication mediated by early or regulatory protein expression. This may be followed, for complex viruses with larger genomes, by one or more further rounds of mRNA synthesis: "late" gene expression is, in general, of structural or virion proteins.(Wiki)
Assembly – Following the structure-mediated self-assembly of the virus particles, some modification of the proteins often occurs. In viruses such as HIV, this modification (sometimes called maturation) occurs after the virus has been released from the host cell. (Wiki)
Release – Viruses can be released from the host cell by lysis, a process that kills the cell by bursting its membrane and cell wall if present: this is a feature of many bacterial and some animal viruses. Some viruses undergo a lysogenic cycle where the viral genome is incorporated by genetic recombination into a specific place in the host's chromosome. The viral genome is then known as a "provirus" or, in the case of bacteriophages a "prophage". (Wiki) Whenever the host cell divides, the viral genome is also replicated. The viral genome is mostly silent within the host. At some point, the provirus or prophage may give rise to active virus, which may lyse the host cells.[Wiki] Enveloped viruses (e.g., HIV) typically are released from the host cell by budding. During this process the virus acquires its envelope, which is a modified piece of the host's plasma or other, internal membrane.
Types of viruses include (in no particular order) common cold, influenza, polio, HIV, HPV (Human papilloma virus), Hepatitis A, B, C, Herpes, Zoster (chicken pox), Rotovirus, Avian flu, SARS, Coronavirus, Influenza A subtype H1N1, measles, Rubella.
Viruses are very pretty and have amazing designs!
On the whole, viruses are quite fragile in structure and generally have short life spans outside of a living host.
Without becoming OCD about cleaning, basic hand washing, covering your mouth and nose, throw away tissues and being conscious of those around you, are still some of the best ways to keep a virus to yourself. Soap breaks the fatty cell membrane thus destroying the genetic material and hence virus. Its hard to say what is "over sanitising" but if you do make everywhere too sterile, environment, skin, insides, you risk depleting your "good" bacteria (85% of the microbiota population) and allowing opportunistic microorganisms such a pathogenic bacteria (15% of microbiota population), viruses, fungi (e.g. thrush/Candida albicans) and other parasites (eg. non beneficial worms), to colonise and secondary infections arise. Keep houses as well ventilated as possible to avoid mould growth and risk of chest infections including pneumonia.
Antibiotics do not treat virus infection and unless it is a gastro virus, hoarding toilet paper is also not a warranted method.
What are Primary and Secondary Immune Responses?
When we first come into contact with a pathogen, bacterial, viral, animal, fungal, even food, our body will respond by wanting to remove it if recognised as "foreign.
With a bacteria and a virus, the body will produce antibodies in 2 stages - primary and secondary.
This can occur naturally or via a vaccine. Re vaccine, this is why 2 doses are required - to imitate the body's natural response. Booster shots may also be required with some viral infections, for others such as the flu, yearly vaccine for a different strain. Homeopaths can aslo provide remedies for viral infections and vaccines. Consult with a Registered Homeopath for more advice.
Antibodies produced in the primary infection will fight the antigen (foreign body) and also produce Memory cells which will act if the person comes into contact again with the same antigen ie secondary infection.
Types of Immunity
Immunity can be divided into 4 main types and we acquire these over our lifetime.
Type 2 Diabetes, Glucose and Insulin
The main aim of taking in food as fuel is to produce Energy. Although the body can convert proteins and lipids (fat & oils) into Energy, the body's preferred and usual source come from carbohydrates.
The main organ of regulation is the Pancreas. Other structures involved include the liver, the brain and muscles, adipose tissue (fat) and the circulatory system/blood.
To produce energy, glucose is used during the process of Respiration, combined with oxygen, will produce the energy needed. This is called Aerobic respiration ie. with oxygen. Glucose can also be used without oxygen. This is called Anaerobic Respiration.
This all takes place in the cell.
There are number of hormones in the pancreas that assist in regulation of both "sugars" and "fats" (endocrine). There are also other cells (exocrine) that are involved in carbohydrate, protein and lipid digestion which are part of the whole picture of blood glucose regulation. I am focusing on beta cells and Insulin.
However, in order for any energy to be produced the glucose has to "get into" the cell.
This is where the hormone INSULIN is involved. Insulin is produced in the Pancreas in specialized cells in the Islets of Langerhans called beta cells.
Insulin is produced by signals from the brain indicating that the glucose in circulation is too high.
Glucose is a large molecule and too big to simply pass through the cell membrane into the cell's cytoplasm (fluid) so Insulin acts like a "boat" to transfer the Glucose.
Overviewof Type 2 Diabetes
In a normal situation, there is a balance of blood glucose and insulin in relation to food intake. Insulin produced, glucose taken into cells, used to make energy.
In a Type 2 Diabetic situation, Insulin will still be produced in most cases. However, if there is a continued high intake of carbohydrates, (above daily recommended levels) and types eg. refined, the brain keeps "telling" the pancreas to produce more insulin.
The pancreas struggles to produce more Insulin and therefore less glucose is moved into the cells.
Eventually the pancreas/beta cells are exhausted. If this is not addressed by diet (and in some cases, medication and insulin), a condition called Insulin Resistance occurs.
As noted in "In the News" section, there are now identified several types of "diabetes" with similar and different symptoms. Regulation of blood glucose and insulin levels are common to all.
Diet is crucial to management in all types. Food in relation to Type 2 Diabetes is discussed further in "Food & Nutrition Basics", "Nutritional Medicine" and "Focus on Micronutrients" Sections. Exercise/movement is also vital to management. This is discussed in the "Let's Move" Sections.
Weight, Weight loss and Metabolism
Your individual metabolism is determined by a few factors - your genetics, your gender and your age. It is also affected by your physical activity level (PAL) and the Thermogenic Effect of Food (TEF - energy required to utilise food). Your daily total energy intake (TEI) is the amount you need to take in daily and your total energy expenditure (TEE) is the effect of food, exercise and bodily functioning that maintain your current weight. You need to adjust these in order to lose weight.
Your brain does have a tendency to want to bring your weight to its determined set point..not always what we want it to be!
Whilst it is true that our metabolic rate declines in efficiency as we age, it can be improved with exercise and a balanced diet.
Another misconception is that overweight/obese people have a "slow" metabolism..in fact, as there are more fat cells to feed, the rate is actually higher. People who are in the right weight to height balance for their gender and age have a more efficient metabolism.
However, disease does play a role, in particular re the thyroid gland (located in the neck and responsible for metabolism of all the body's cells and functioning). If you are following a dietary plan and exercising a getting no where, see your GP for a thyroid test.
In women, weight gain can be due to oestrogen and progesterone hormones, menstrual cycles and pre menopause. Whilst these can be tested, if they come back in "normal range", don't give up. A Naturopath with herbal qualifications can assist.
Weight loss is also about mental health, if you are stressed, the hormone cortisol is produced. In the morning this is naturally higher, delaying eating immediately upon waking can assist in weight loss and letting cortisol do its job.
If you maintain high levels of cortisol - the stress hormone, you will gain weight, especially around the hips, stomach and thighs. Cortisol can also deplete immune system and if you add poor sleep on to this, weight loss in many is a struggle. Again, see your GP and specialist nutritionists.
See Focus on Micronutrients for information on B vitamins that aid in metabolism and stress management.
Make sure also that you are not consuming too few calories, less than 1000cals (4200KJ) on a continual basis can cause storage and weight gain.
Continual "dieting" does mess with your metabolism and if you have been "dieting" since young and now older, you may be finding reduced calorie dieting and excessive exercising doesn't work - so STOP dieting and live..you never know, that may be the key to losing those extra kilos!
Whether you lose, gain or maintain weight again comes back to your genes but you can aim for a healthy weight and lifestyle.
Scroll further down this blog for information on Digestion, Absorption & Metabolism.
What is a Vitamin D? Vitamin or Hormone??
Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects.
There are 5 known compounds - D1, D2, D3, D4 & D5. In humans, the most important compounds in this group are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). Collectively known as Calciferol.
As vitamin D can be synthesized in adequate amounts by most mammals exposed to sufficient sunlight, it is not an essential dietary factor, although not technically a vitamin. It could be considered a hormone, with activation of the vitamin D pro-hormone resulting in the active form, calcitriol, which then produces effects via a nuclear receptor in multiple locations.
People mistakenly think that it comes from the sun and has been called the “sunshine vitamin”.
The major natural source of the vitamin is production of cholecalciferol in the lower layers of skin epidermis through a chemical reaction that is dependent on sun exposure (specifically UVB radiation). You can also obtain Cholecalciferol and Ergocalciferol from the diet and from supplements. Discussed further in Nutritional Medicine & Focus on Micronutrients sections.
Vitamin D from the diet, or from skin synthesis, is biologically inactive. A protein enzyme must hydroxylate it to convert it to the active form.
This is done in the liver and in the kidneys. Cholecalciferol is converted in the liver to calcifediol (25-hydroxycholecalciferol); ergocalciferol is converted to 25-hydroxyergocalciferol. These two vitamin D metabolites (called 25-hydroxyvitamin D or 25(OH)D) are measured in serum to determine a person's vitamin D status.
Allergy or Intolerance?
These two words are often used interchangeably but they are not the same and should not be used as if they were.
What is an allergen?
An allergen is a substance to which as person's immune system overreacts ie. has an allergic response.
Most allergens are proteins eg. food protein, bacteria, dust mites, bee stings; however, they can be carbohydrate eg. mammalian meat allergy (from ticks) "alpha-gal" allergy.
Cells called Mast cells respond by releasing a chemical called histamine.
This in turn produces symptoms associated with an allergic response ie. sneezing, runny eyes, skin rashes and tiredness.
As most allergies are genetic based the conditions often seen associated with the allergy are asthma, hay fever, hives along with stages of inflammation, vomiting, wheezing, localised redness and swelling, eczema.
An allergy involves the immune system Immunoglobulin E (IgE).
Allergies are life threatening and should not be ignored as anaphylaxis can result in death. If allergy is known, an epi-pen needs to be carried at all times. Foods must be avoided.
Current research into the gut biome are showing a correlation between poor gut flora and rise in allergies.
What is Intolerance?
An intolerance will certainly show mild to severe symptoms such as hives/rashes, nausea/vomiting, bloating, alternate diarrhea/constipation when certain foods are eaten from any food group.
Continued consumption of the food/foods may weaken intestinal tract integrity (leaky gut syndrome) and peristalsis in both small and large intestine and also weaken the immune system but does not cause the release of IgE. It can cause malnutrition due to incomplete digestion and malabsorption.
Symptoms usually go away with avoidance, reduction in quantity & frequency and improvement of quality including using biodynamic or organic.
Testing & Diet Plans
Your GP can arrange a skin prick test as a start, an allergy specialist may then do serum testing. Specialist Dietitians will devise a programme for those with diagnosed Allergy. For diagnosed Food Intolerance, a Naturopath with herbal medicine qualifications or a Nutritionist specialising in Nutritional Medicine can assist in devising a menu plan.
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