Mercury

December 29, 2011 by  
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Toxic element

One of the group of so-called heavy metals which accumulate in the body, mercury has been described as one of the most toxic substances known to man, particularly the organic forms of mercury such as methylmercury and ethylmercury. These forms are created by micro-organisms in the sea and lakes, from inorganic mercury salts which have been discharged in industrial effluent. Fish consume the plankton which contain these toxic forms of mercury, and humans can be poisoned by the fish, especially the larger varieties such as tuna, which can accumulate quite large quantities of mercury from eating many smaller fish. In 1953, when mercury was accidentally discharged into Minamata Bay in Japan, 46 people died after eating mercury-contaminated fish. Poisoning by organic mercury has also occurred in Iraq, Guatemala and Pakistan, when people consumed grains which had been dressed with mercury fungicides. These grains were not intended for human consumption but for planting. Humans also suffered mercury poisoning after eating animals which had been fed with such grains.

Other sources of mercury include:

  • Accidental breaking of thermometers, discarded batteries and mercury vapour lamps
  • Amalgam in silver tooth fillings
  • Coal burning
  • Fungicides sold for use on lawns and gardens
  • A wide variety of industrial processes.
  • Medicines such as calomel talc
  • Some ethnic cosmetics and medicines

As shown by studies on animals given amalgam tooth fillings, mercury mainly accumulates in the kidneys; the minute amounts of mercury which come out of the teeth during chewing and are then swallowed, can in time result in a loss of 50 per cent of kidney function. (Drasch G et al: Quecksilberkonzentration in der Nierenrinde. 6th International Trace Element Symposium, Leipzig, 1989.)

A large number of enzymes in the body can be inactivated by mercury, and toxicity symptoms can include insomnia, dizziness, chronic fatigue and weakness, depression, tremors, nervousness, poor co-ordination and dermatitis. Mercury alters protein structure, rendering it unusable. It interferes with sulphur binding sites and can therefore impair insulin synthesis and haemoglobin function. These symptoms may progress to kidney damage and brain damage. Insanity is a typical sign of severe mercury poisoning. The mental illness known as ‘general paralysis of the insane’ or tertiary syphilis, was very common before the advent of modern treatments for syphilis, and is now known to have probably been caused by poisoning due to the old-fashioned anti-syphilis treatments which were based on mercury, antimony and arsenic.

Some individuals can develop a sensitivity to mercury which makes them susceptible to it in different ways. Many cases of auto-immune diseases such as multiple sclerosis, diabetes and systemic lupus erythematosus have responded to the removal of mercury amalgams from teeth. An increasingly common condition known as multiple allergy syndrome (in which the sufferer is allergic to many different foods and other substances) may also respond to the removal of mercury amalgams. These successes may be explained by the fact that the mercury acts as a constant source of stress to the body’s detoxification system, which may recover and work normally once this stress has been removed.

Dentists are at particular risk of mercury poisoning, since they are exposed to mercury vapour, which when inhaled through the nose quickly reaches the brain. The trace element selenium helps to protect against mercury’s toxic effects.

Leaky gut syndrome

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Apart from its functions as a digestive/absorptive organ, the small intestine also acts as a barrier to prevent potentially damaging substances in the intestine from entering the bloodstream. These include bacteria, bacterial cell wall polymers, chemotactic peptides, bacterial antigens capable of inducing antibodies, and bacterial and dietary antigens which can form systemic immune complexes.

If the integrity of the gut becomes impaired, this may result in the enhanced uptake of large inflammatory molecules and pathogenic (disease-causing) bacteria. Some of the factors which may damage the gut wall include: chronic allergic inflammation, chronic irritation due to non-steroidal anti-inflammatory drugs, or chronic irritation due to dysbiosis, parasites, or to the continual presence of too much inadequately digested food. Alcoholism, cancer chemotherapy and Aids are also associated with increased gut permeability, leading to ‘leaky gut syndrome’.

The symptoms of this condition may be non-specific: swelling and bloating of the abdomen, symptoms of an increased toxic load on the liver, such as the development of food allergies and chemical sensitivities, and increasing symptoms of nutritional deficiency as nutrient absorption worsens. (Paradoxically, while permeability to large molecules may increase due to the increased porosity of intercellular junctional complexes, permeability to small molecules decreases due to atrophy of the microvilli). According to the scientific literature, increased gut permeability appears to correlate with a number of frequently seen clinical disorders, including:

  • Allergic disorders
  • Ankylosing spondylitis
  • Chronic dermatological conditions
  • Coeliac disease
  • Crohn’s disease
  • Food allergy
  • Inflammatory bowel disease
  • Inflammatory joint disease
  • Rheumatoid arthritis
  • Schizophrenia

The permeation of water-soluble molecules through the intestinal mucosa can occur either through cells (transcellular uptake) or between cells (paracellular uptake). Small molecules such as glucose and mannitol readily penetrate cells and passively diffuse through them. Larger molecules such as disaccharides (e.g. lactulose, sucrose) are normally excluded by cells. Leaky gut syndrome can therefore be diagnosed by measuring the ability of mannitol and lactulose to permeate the intestinal mucosa. Mannitol serves as a marker of transcellular uptake, and lactulose, being only slightly absorbed, serves as a marker for mucosal integrity. To perform the test, the patient mixes pre-measured amounts of lactulose and mannitol and drinks the challenge substance. The test – which is available through nutritional therapists – measures the amount of lactulose and mannitol recovered in a 6-hour urine sample. Low levels of mannitol and lactulose indicate malabsorption. Elevated levels of lactulose and mannitol are indicative of general increased permeability and leaky gut syndrome. An elevated lactulose/mannitol ratio indicates that the effective pore size of the gut mucosa has increased, allowing larger molecules to access the bloodstream, where they are capable of provoking allergic reactions.

Iron deficiency anaemia may cause leaky gut syndrome in babies and young children. (Berant M et al: Effect of iron deficiency on small intestinal permeability in infants and young children. J Pediatr Gastroeneterol Nutr 14(1):17-20, 1992).

Hormones

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Substances produced in one part of the body (often called a ‘gland’) which regulate the activity of an organ or group of cells in another part of the body.

The major hormones and their effects

Gland Hormone Controls
Anterior pituitary. Growth hormone. Growth and metabolism.
Thyroid-stimulating hormone. Thyroid gland.
Adrenocorticotrophic
hormone (ACTH)
Adrenal cortex.
Gonadotropic hormones (follicle-stimulating
hormone and luteinizing hormone)
Gonads (reproductive glands).
Posterior pituitary Oxytocin Milk ‘let-down’. Uterine motility.
Antidiuretic hormone Water excretion by the kidneys.
Adrenal
cortex
Cortisol Metabolism. Stress response.
Androgens Male characteristics. Sex drive in men and women.
Aldosterone Excretion of sodium and potassium by the kidneys.
Adrenal medulla Adrenaline (epinephrine) Metabolism. Stress response.
Noradrenaline (norepinephrine) Metabolism. Stress response.
Thyroid Thyroxine and
triiodothyronine
Energy, metabolism and growth.
Calcitonin Calcium balance in blood.
Parathyroid glands Parathyroid hormone Calcium and phosphate balance in blood.
Pancreas Insulin
Glucagon
Somatostatin
Metabolism. Blood sugar control.
Ovaries Oestrogen and progesterone. Reproductive system in women. Female characteristics.
Testes Testosterone Reproductive system in males. Male characteristics.
Pineal Melatonin Diurnal rhythms (sleep and waking).

Also see Endocrine system and individual hormones.

Glycaemic index

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A measure of a food’s effect on blood sugar levels. Foods with a low glycaemic index resulting in the slow absorption of sugars from the diet, a modest rise in blood glucose, and a smooth return to normal are considered desirable. Foods with a high glycaemic index result in the fast absorption of sugars and a surge in blood glucose levels. This is particularly undesirable for diabetics. In individuals with a tendency to reactive hypoglycaemia such foods eaten in excess may result in a subsequent surge in insulin levels leading to rebound low blood sugar within a few hours after eating.

Some foods with a high glycaemic index Some foods with a moderate glycaemic index Some foods with a low glycaemic index
Bananas
Beetroot
Bread (wholemeal and white)
Broad beans (fresh)
Carrots
Corn chips and cornflakes
Honey
Instant potato
Low-fat ice-cream
Millet
Puffed wheat
Muesli
Raisins
Rice (both brown and white)
Rye and wheat crackers
Shredded wheat
Buckwheat
Canned beans (unless sugar-free)
Chocolate
Digestive and oatmeal biscuits
Oranges and orange juice
Pasta
Peas
Potato crisps (fried)
Pumpernickel
Rich Tea biscuits
Spaghetti
Sugar (sucrose)
Sweetcorn
Sweet potato
Yams
Apples
Black-eyed beans
Butter beans (lima beans)
Chick peas
Fructose
Grapefruit
Grapes
Haricot (white) beans
Ice-cream (except low-fat)
Kidney beans
Lentils
Milk
Nuts
Oatmeal
Pears
Soya beans
Yoghurt

Ginseng

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Two main types of ginseng are used as medicines.

Korean ginseng

Korean, or Panax ginseng, is one of the oldest medicinal herbs in the Far East, and has undergone considerable research. It is used short-term as a tonic to treat fatigue, low blood pressure, general and nervous weakness and mild depression, and long term to improve well-being in the elderly.

Research studies have demonstrated the following benefits for Korean ginseng:

  • Ability to normalize high or low blood pressure in some individuals
  • Improvements in liver detoxification function
  • Improvement in overall well-being (including appetite, mood and sleep)
  • Improvement in physical endurance, mental ability and concentration
  • Improvements in serum total cholesterol levels
  • Reduction of insulin requirements in diabetics

Korean Ginseng appears to act as an adaptogen, that is to say it has neither an excessively stimulating nor a sedating effect, but is capable of acting in either direction depending on the individual’s needs.

In Chinese medicine, Korean ginseng is used to increase deficient chi, (a type of energy which has been likened to the elusive ‘life force’), with symptoms of debility, irritability, poor circulation and prolapse of the lower abdomen. Its beneficial effects in the elderly may be related to its ability to maintain the adrenal cortex in an optimally functioning condition.

Korean ginseng should not be taken by individuals with cardiovascular disease or by women with an unstable menstrual cycle.

Siberian ginseng

Also known as Eleutherococcus, Siberian ginseng is used as a ‘harmonizing’ tonic. Like Panax ginseng, Eleutherococcus is considered to be an adaptogen – adapting its effects to the indivdual’s needs. This herb has undergone much study by scientists in the former USSR. It has been found to provide the following benefits:

  • Ability to improve capillary resistance
  • Ability to perform physical work
  • Ability to withstand motion sickness
  • Adaptation to a high temperature environment
  • Improvement in acute craniocerebral trauma
  • Improvement in acute pyelonephritis
  • Improvement in atherosclerosis
  • Improvement in chronic bronchitis
  • Improvement in diabetes mellitus
  • Improvement in oxygen metabolism (i.e. oxygen uptake, oxygen pulse, total work and exhaustion time)
  • Improvement in rheumatic heart disease
  • Improvement in speed and quality of work
  • Normalizing of high or low blood pressure
  • Stimulation of the white cells of the immune system, especially the T-lymphocyte cell count.

Flavonoids

December 28, 2011 by  
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Also see Bilberry

Also known as bioflavonoids, flavonoids are colourful antioxidants found in plants. They are responsible for the colours of fruits (e.g. the red or blue of grape and berry skins) and vegetables. Twelve basic classes (chemical types) of flavonoids have been recognized: flavones, isoflavones, flavans, flavanones, flavanols, flavanolols, anthocyanidins, catechins (including proanthocyanidins), leukoanthocyanidins, chalcones, dihydrochalcones, and aurones. Anthocyanidins and closely related flavonoids such as proanthocyanidins may collectively be referred to as anthocyanosides.

Apart from their antioxidant activity, flavonoids are known for their ability to strengthen capillary walls, thus assisting circulation and helping to prevent and treat bruising, varicose veins, bleeding gums and nosebleeds. They may also be useful in the treatment of heavy menstrual bleeding, where no apparent cause for this is found on medical investigation. A third beneficial effect of some flavonoids such as quercetin, rutin, curcumin, silymarin and green tea polyphenols is their reputed anti-inflammatory effect, which may be related to their ability to inhibit the enzymes cyclo-oxygenase and lipoxygenase, which can act on arachidonic acid in cell membranes to form potent inflammatory substances known as prostaglandins, some of which promote swellings and possibly symptoms such as headaches, rashes and joint pains.

Lemons (outer skin and white pith), and the central white core of citrus fruit generally, are a particularly rich source of flavonoids. The white pith of green peppers is also rich in flavonoids, as is the skin of colourful berries and grapes. Some herbs (such as Ginkgo biloba) are taken partly for the action of their flavonoids.

The names of some of the flavonoids

Anthocyanidins Blue pigments (which may appear red under some conditions) found in the skins of some berries, especially bilberries. Beneficial effects on eyesight and circulation, and some antibacterial action.
Hesperidin Found in citrus peel. Improves abnormal capillary fragility.
Myricetin One of the beneficial antioxidants found in Ginkgo biloba. Helps to prevent free radical damage to nerve cells.
Nobiletin Found in citrus fruits. Has anti-inflammatory action and assists detoxification.
Proanthocyanidins (also
known as pycnogenols)
Related to tannins, these are polyphenolic flavonoids found in pine bark, tea, peanut skins, cranberries and grape seeds and skins. Their antioxidant potency (particularly the varieties found in grape seeds) is reputedly 20 times greater than that of vitamin E.
Quercetin Found in apple peel, onions, tea, Ginkgo biloba and cabbage. Helps to prevent cataract formation. May help allergy-related problems such as hay fever, asthma and eczema. Promotes the more efficient cross-linking of collagen. Quercetin is structurally related to the anti-allergic drug disodium chromoglycate.
Rutin Found in buckwheat. Helps in the treatment of high blood pressure, bruising and haemorrhages under the skin, including redness due to radiation.

Fats

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Also known as lipids, fats are components of the diet and the human or animal body which are insoluble in water but soluble in organic solvents. Fats may be solid or liquid, in which case they are known as oils. Butter, lard, meat fat, oils and margarine are the foods with the highest fat content.

Some high-fat foods

  • Cakes, cookies and biscuits
  • Cheese (especially cream cheese and processed cheese)
  • Cheesecake
  • Chips
  • Chocolate
  • Creamy desserts
  • Creamy dips (e.g. taramasalata)
  • Creamy sauces (e.g. mayonnaise, Hollandaise)
  • Crispy snacks
  • Dairy cream
  • Deep-fried foods
  • Fatty meats (e.g. burgers, streaky bacon, salami, sausages)
  • French fries (especially if thinly cut)
  • Fried bread
  • Fritters and batter
  • Ice cream
  • Pastries, croissants
  • Pâté
  • Pork pies

The fat content of food plays a large part in its palatability. For instance the taste of meat comes from the flavour of its fat. Fat makes ice cream creamy and pastry crumbly or flaky. Without fat, cakes become rubbery and milk watery. Many people eat a high-fat diet (the average in the western diet is around 40 per cent of the total calorie intake) without realizing this, owing to large quantities of fats being hidden in processed foods such as biscuits and burgers. The law in most countries compounds the problem; for instance in the UK meat may legally be described as ‘lean’ even if it is one third fat.

Essential chemistry

Dietary fats and oils are composed of units called triglycerides. A triglyceride consists of three fatty acids attached to a ‘backbone’ of glycerol.

Fatty acids are made from chains of carbon, hydrogen and oxygen. They are classed as ‘essential’ or ‘non-essential’, depending on whether the body is capable of synthesizing them or not. Those which it cannot make and must obtain from the diet are known as essential fatty acids (EFAs). A deficiency of EFAs can have a widespread impact on health.

Fatty acids are classified according to four characteristics:

  • Whether or not they are essential
  • The length of the chain
  • Whether they are saturated or unsaturated
  • The position of the first double bond (see diagram on previous page).

Linoleic acid, which is an essential fatty acid, belongs to the family of ‘omega 6’ fatty acids because the first double bond appears after the sixth carbon atom. The other essential fatty acid is known as alpha linolenic acid. It belongs to the family of ‘omega 3’ fatty acids because the first double bond appears after the third carbon atom. Fish oil also belongs to the omega 3 family of fatty acids. Most vegetable oils mainly comprise omega 6 fatty acids.

Good food sources of linoleic acid

  • Corn oil
  • Fresh nuts and seeds
  • Groundnut oil
  • Safflower oil
  • Sunflower seed oil

Good food sources of alpha linolenic acid

  • Linseed (flax seed) oil
  • Soybean oil
  • Leafy vegetables
  • Walnuts

Saturated fats are not essential and have no double bonds—all the carbon atoms in their fatty acid molecules are attached to a hydrogen atom. Monounsaturated fatty acids, such as oleic acid, found in olive oil, are also non-essential. They have one double bond (one carbon atom is missing a hydrogen atom). Polyunsaturated fatty acids have two or more double bonds. The more unsaturated a fat, the more it tends to be liquid at room temperature. However, unsaturated fats can be turned into saturated fats by artificially adding hydrogen atoms which the carbon atoms can attach to. This is how oils can be turned into margarine.

Digestion and metabolism

After a meal, emulsified fat droplets are absorbed from the gut into the lymphatic system and then drain into the bloodstream at the thoracic duct in the neck. Within hours, the triglycerides are broken down into fatty acids and glycerol and then removed from the blood and into the adipose (fat) cells where they are reconstituted into triglycerides. In short, they are added to your body fat. This is the ultimate fate of saturated fats.

EFAs on the other hand have a more vitamin-like purpose. EFAs are broken down by the enzymes shown in the diagram below and turned into prostaglandins (sometimes known as eicosanoids). These are hormone-like substances which when out of balance can cause disorders such as high blood pressure, arthritis, menstrual pain, allergies, asthma, eczema, migraine and fertility problems. Series 1 and 3 prostaglandins are beneficial, but series 2 prostaglandins can encourage inflammation in the body.

The enzyme delta-6-desaturase (D-6-D) in the diagram is vital to metabolize EFAs. EFA deficiency symptoms (which are really prostaglandin deficiency symptoms) can develop if this enzyme is not present in sufficient amounts. Factors which can reduce its efficiency include:

  • A high intake or blood level of cholesterol
  • A high intake of saturated fats and trans fats
  • High adrenaline levels
  • A high alcohol consumption
  • Diabetes
  • Atopy (an inherited susceptibility to allergic diseases)
  • Deficiencies of magnesium, vitamin B6, biotin or zinc.

Some health problems which make us suspect a deficiency of EFAs or prostaglandins include:

  • Dry eyes
  • Eczema, psoriasis or dry skin
  • Inflammatory disorders of all types
  • Premenstrual syndrome (especially breast pain)
  • Tendency to clot formation in blood
  • Split fingernails
  • Ear problems
  • Hyperactivity in children
  • Extreme thirst and general dryness

Dietary fibre

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That portion of our diet which is not broken down by our digestive enzymes and does not therefore serve as a (direct) source of nutrients. Also known as non-starch polysaccharides. Fibre is not, as is often thought, calorie-free; bacteria digest soluble fibre to form short-chain fatty acids, principally acetate, propionate and butyrate, which are used as energy sources for the intestinal lining (mucosa) and can also be absorbed into the bloodstream.

Dietary fibre holds water and thus softens the stools and adds bulk, assisting stool propulsion (peristalsis) and evacuation. Diets low in fibre promote constipation.

Types of dietary fibre

Cellulose Insoluble Less digestible by bacteria. Adsorbs bile acids and cholesterol. Found in plant cells walls (e.g. leafy vegetables, peas, beans, wheat bran)
Gums Soluble Can be digested by bacteria. Adsorb bile acids and cholesterol. Retard the rate of absorption of simple sugars from the small intestine. Found in seeds and plant secretions. May be used as food additives.
Hemicellulose Insoluble Less digestible by bacteria. Adsorbs bile acids and cholesterol. Found in plant cell walls
Inulin Soluble Can be digested by bacteria Found in Jerusalem artichokes
Lignins Insoluble Less digestible by bacteria. Adsorb bile acids and cholesterol. Found in bran
Mannosans, raffinose, stachyose, verbacose Soluble Can be digested by bacteria Found in pulses (legumes)
Mucilages Soluble Can be digested by bacteria Found in seeds (e.g. psyllium) and seaweeds
Pectins Soluble Can be digested by bacteria. Adsorb bile acids and cholesterol. Retard the rate of absorption of simple sugars from the small intestine. Found in fruit and vegetables, especially apple peel and the white part of citrus fruit

Detoxification

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One of the body’s most vital functions is to convert metabolic products and toxins into soluble, safe substances which can then be eliminated via the urine or via the gall bladder into the intestines. The liver plays an all-important role in this process, which is known as detoxification or biotransformation.

Recent research has shown that many patients with chronic fatigue syndrome or ME have a disordered liver biotransformation ability. We simply don’t know what other diseases and health disorders may be promoted by a toxic overload resulting from such dysfunction, but progress is beginning to be made in looking at specific detoxification pathways and relating underfunctioning of these to the development of diseases like Parkinsonism, motor neurone disease (also known as ALS) and Alzheimer’s disease.

A number of biochemical pathways are involved in liver biotransformation. These are normally grouped into oxidation, reduction or hydrolysis reactions (Phase I) and conjugation reactions (Phase II).

Phase I detoxification

Phase I reactions, which are catalysed by a group of liver microsomal enzymes known as cytochrome P450 oxidases, introduce oxygen into the structure of toxins or metabolites. Typically the toxins are converted to alcohols and aldehydes by this process, then into acids, which are water-soluble and can be excreted via the urine.

The intermediate substances created during Phase I detoxification, which include reactive oxygen species (free radicals), can be extremely toxic – far more so than the original toxins. Their harmful effects are primarily controlled by antioxidant nutrients and enzymes, therefore a plentiful supply of these substances is essential. Apart from free radicals, other intermediate metabolites include epoxides, chloral hydrate (which is identical to the knock-out drug often known as the ‘Mickey Finn’) and endogenous benzodiazepines – substances similar to Valium and other tranquillizers and sleeping pills. This makes it easier to understand how chronic fatigue can develop when a toxic overload is present.

The more P450 enzymes have to be induced, the more toxic intermediates will be present in the human body. These enzymes are induced by caffeine, alcohol, dioxin and other pollutants, exhaust fumes, high protein diets, oranges and tangerines, organophosphorus pesticides, paint fumes, steroid hormones, and a variety of drugs including paracetamol (acetaminophen), diazepam tranquillizers and sleeping pills, the contraceptive pill and cortisone. Substances which can inhibit P450 enzymes include carbon tetrachloride, carbon monoxide, barbiturates, quercetin and naringenin (found in grapefruit). The oxidation reaction can also be blocked by an excess of toxic chemicals, a lack of enzymes, lack of nutrients and/or loss of oxygen. Such blocking results in a build-up of more toxic substances such as formaldehyde and other aldehydes in the target tissue. This can in turn lead to a spreading phenomenon, with increasing sensitivity to more chemicals such as ketones and alcohols, and eventually even to natural chemicals occurring in foods, pollen and mould. A build-up of aldehydes can in severe cases lead to tissue crosslinking, causing vasculitis with possible seizures and brain damage.

Intestinal overgrowth with Candida albicans, as well as the peroxidation of polyunsaturated fats, are known sources of aldehydes. The fatigue, foggy thinking and ‘brain fag’ linked with candidiasis may be due to an overloading of the detoxification system with aldehydes, which can even lead to a reverse reaction of aldehyde to alcohol. Extreme intolerance to alcohol consumption may occur in these individuals, as it does in those diagnosed with ME or chronic fatigue syndrome.

Although most aldehydes in the body are thought to occur as intermediate metabolites, external sources include exposure to formaldehyde gas (which is given off by new carpets, curtains and other furnishings) and breakdown products of ethylene glycol and methanol.

Cytochrome P450 and other oxidizing enzymes also oxidize amines such as phenylethylamine found in chocolate, tyramine found in cheese, and catecholamines (adrenaline, noradrenaline and dopamine). These are oxidized into aldehydes by mitochondrial monoamine oxidase (MAO). If this enzyme is blocked, for instance by MAO inhibitor drugs used to treat depression, tyramine, for instance, cannot be metabolized and hypertension can develop as a chemical sensitivity reaction.

Phase II detoxification (conjugation)

There are five main conjugation categories, including acetylation, acylation (peptide conjugation with amino acids), sulphur conjugations, methylations and conjugation with glucuronic acid. Some substances enter Phase II detoxification directly, others come via Phase I pathways. Conjugation involves the combining of a metabolite or toxin with another substance which adds a polar hydrophilic molecule to it, converting lipophilic substances to water-soluble forms for excretion and elimination. Individual xenobiotics and metabolites usually follow a specific path, so whereas caffeine is metabolized by P450 enzymes, aspirin-based medications are conjugated with glycine, and paracetamol (acetaminophen) with sulphate.

Acetylation

Acetylation requires pantothenic acid to function. It is the chief degradation pathway for compounds containing aromatic amines such as histamine, serotonin, PABA, P-amino salicylic acid, aniline and procaine amide. It is also a pathway for sulphur amides, aliphatic amines and complex hydrazines.

A proportion of the general population – perhaps up to 50 per cent – are slow acetylators. This rises to as high a level as 80 per cent among the chemically sensitive population. Their N-acetyltransferase activity is thought to be reduced, and this prolongs the action of drugs and other toxic chemicals, thus enhancing their toxicity.

Acylation

Acylation uses acyl CO-A with the amino acids glycine, glutamine and taurine. Conjugation of bile acids in the liver with glycine or taurine is essential for the efficient removal of these potentially toxic compounds. Disturbed acylation by pollutant overload decreases proper levels of bile in the gastrointestinal tract, resulting in poor assimilation of lipids and fat-soluble vitamins, and disturbed cholesterol metabolism.

Toluene, the most popular industrial organic solvent, is converted by the liver into benzoate, which, like aspirin and other salicylates, must then be detoxified by conjugation with the amino acid glycine (glycination). Large doses of glycine and N-glycylglycine are used in treating aspirin overdose. Benzoate is present in many food substances and is widely used as a food preservative.

Glycine is a commonly available amino acid, but the capacity to synthesize taurine may be limited by low activity of the enzyme cysteine-sulfinic acid decarboxylase. Damage can occur to this enzyme directly by pollutants, or by overload/over-use resulting in depletion.

Both taurine- and glycine-dependent reactions require an alkaline pH: 7.8 to 8.0. Environmental medicine specialists may alkalinize over-acidic patients by administering sodium and potassium bicarbonate in order to facilitate these reactions.

Glutathione conjugation, using the amino acid glutathione in its reduced form, is used for the transformation of xenobiotics such as aromatic disulphides, naphthalene, anthracene, phenanthacin compounds, aliphatic disulphides and the regeneration of endogenous thiols from disulphides. There is a cycle of replenishment for glutathione, allowing it to be reformed after conversion to glutathione reductase. Heavy metals can inhibit this cycle, thus preventing replenishment.

Sulphate conjugation (sulphation)

Neurotransmitters, steroid hormones, certain drugs and many xenobiotic and phenolic compounds such as oestrone, aliphatic alcohols, aryl amines and alicyclic hydroxysteroids employ sulphation as their primary route of detoxification. Steventon at Birmingham University (UK) has found that many sufferers from parkinsonism, motor neurone disease and Alzheimer’s disease as well as environmental illness, tend to have a reduced ability to produce sulphate from the amino acid cysteine in their body, and instead accumulate cysteine. Sulphate may be ingested from food, but is also produced by the action of the enzyme cysteine dioxygenase on cysteine. This process is known as sulphoxidation. The body’s ability to conjugate toxins with sulphate is ‘rate limited’ by the amount of sulphate present; if there is inadequate sulphate, toxins and metabolites can accumulate, perhaps building up to levels which cause degeneration of nervous tissue after several decades. Steventon’s findings are a matter for serious concern. How many individuals are given the opportunity to find out whether they are poor sulphoxidizers and to reduce their chances of developing the above mentioned diseases by improving their sulphoxidation ability?

Large doses of N-acetyl-cysteine (NAC) are a standard treatment for paracetamol (acetaminophen) overdose.

Methylation

According to environmental medicine specialist William Rae, the process most often disturbed in the chemically sensitive involves methylation reactions catalysed by S-adenosyl-L-methonine-dependent enzymes. Methionine is the chief methyl donor to detoxify amines, phenols, thiols, noradrenaline, adrenaline, dopamine, melatonin, L-dopa, histamine, serotonin, pyridine, sulphites and hypochlorites into compounds excreted through the lungs. Methionine is needed to detoxify the hypochlorite reaction. The activity of the methyltransferase enzyme is dependent on magnesium, and, due to the frequency of magnesium deficiency, supplementation with this nutrient will often stabilize chemically sensitive patients.

Glucuronidation

Glucuronic acid is a metabolite of glucose. It can conjugate with chemical and bacterial toxins such as alcohols, phenols, enols, carboxylic acid, amines, hydroxyamines, carbamides, sulphonamides and thiols, as well as some normal metabolites in a process known as glucuronidation. For most individuals glucuronidation is a supplementary detoxification pathway. It is a secondary, slower process than sulphation or glycination, but is important if the latter pathways are diminished or saturated. Obese people seem to have an enhanced capacity to detoxify molecules that can use the glucuronidation pathway. However, damage to the capacity for oxidative phosphorylation, which takes place in the mitochondria, is likely to diminish the capacity for glucuronide conjugation.

If the liver’s detoxification pathways are excessively stimulated and overly utilized, they eventually become depleted or begin to respond poorly – being suppressed by toxic chemicals. Once breakdown of the main pathways occurs as a result of pollutant overload, toxins are shunted to lesser pathways, eventually overloading them, and disturbing orderly nutrient metabolism. Chemical sensitivity may then occur, followed by nutrient depletion and finally fixed-name disease.

Interesting facts

  • Dr William Rae of the Environmental Health Centre in Dallas says that the most severely ill chemically sensitive patients not only have abnormally low antipollutant enzymes in addition to toxic suppression and nutrient depletion, but in some instances antibodies are produced against cytochrome P450 and these may inhibit or decrease its effectiveness.
  • Environmental medicine specialists have found that almost 35 per cent of chemically sensitive patients are deficient in intracellular sulphur. Not only can this hinder the detoxification of some sulphur-containing and other toxic chemicals, it can enhance the harmful effects of exposure to cyanide from foods such as cassava and almonds as well as from tobacco products. The hereditary disease known as Leber’s optic atrophy involves a genetic defect in the ability to detoxify cyanide, and leads to sudden, permanent blindness on first exposure to cyanide in small amounts such as those ingested from smoking cigarettes.
  • Many practitioner multimineral supplements in the UK omit iron and copper due to theories that individuals may already be overloaded with these nutrients. However if no overload is present, an unbalanced supplement may promote depletion of the minerals. The Environmental Health Centre in Dallas finds that intravenous infusions to replenish iron stores brings dramatic improvements for the chemically sensitive patient as part of their detoxification process. Copper is also found to help catalyze the cytochrome systems. (NB: self-supplementation with iron and copper should be cautious, to avoid iron and copper overload conditions).
  • Although the liver microsomal system is the primary site for oxidation of xenobiotics, the cytochrome P450 system is found in other tissues that are exposed to environmental compounds like the skin, lungs, gastrointestinal tract, kidneys, placenta, corpus luteum, lymphocytes, monocytes, pulmonary alveolar macrophages, adrenals, testes and brain, in both the mitochondria and in the nuclear membrane.
  • Always rinse your washing-up carefully. Pollutants in the form of solvents and detergents can damage and penetrate the cell membrane and damage the contents of the cell.
  • Vitamin B3 has been shown to accelerate the clearance of aldehydes in some chemically sensitive patients.
  • Molybdenum, although an essential element, competes with sulphate in its activation step to the important enzyme PAPS and can thus lower sulphate levels and impair sulphation ability. Environmental medicine experts warn that molybdenum supplementation may be contraindicated in individuals with poor sulphation ability.
  • The substance naringenin, found in grapefruit, can significantly inhibit Phase I detoxification, as can grapefruit itself. This may prove clinically useful in some situations where Phase I activity is too high, (as shown in liver function tests available from nutritional therapists).
  • Persons who have been exposed to toxic chemicals, drugs and other xenobiotics (foreign substances), have increased requirements for some vitamins. Functional nutritional assays for vitamins B1, B2, B3, B6, B12 and folate, and serum levels of vitamins A, D, C and beta carotene were performed in a random sample of 333 environmentally-sensitive patients prior to treatment. 57.8% were found to be deficient in B6, 37.7% in vitamin D, 34.9% in B2, 32.2% in folate, 27.7% in vitamin C, 21.4% in niacin, 14.9% in B12, 5.6% in vitamin A and 4.6% in beta-carotene. (Ross GH et al: Evidence for vitamin deficiencies in environmentally-sensitive patients. Clinical Ecology 6(2):60-6, 1989.)

Foods to aid detoxification

  • Beetroot: helps with liver drainage
  • Broccoli, cauliflower and other cruciferous vegetables: these aid cytochrome P450 activity
  • Protein
  • Radish, watercress: rich in sulphur.

Supplements to aid liver detoxification

  • B complex vitamins
  • Digestive enzymes: may be necessary to ensure that protein is adequately digested and glycine is readily available
  • Essential fatty acids
  • N-acetyl cysteine (NAC)
  • Reduced glutathione
  • Selenium, zinc, magnesium and manganese; possibly iron and copper if used with caution
  • Taurine (a useful combination product is magnesium taurate)
  • Vitamins C and E and beta carotene.

Liver herbs to aid detoxification (traditionally known as ‘blood cleansing’ herbs)

  • Dandelion root: cholagogue (stimulates liver secretions and bile flow)
  • Globe artichoke leaf: promotes regeneration of the liver and promotes blood flow in that organ
  • Silymarin: according to recent research, this herbal extract stabilizes the membranes of liver cells, preventing the entry of virus toxins and other toxic compounds including drugs. Promotes regeneration of the liver.
  • Turmeric: a cholagogue like dandelion, but may irritate the gastric mucosa. Its advantages are its cheapness and ability to be used in cookery.

These herbs are best taken with strong chamomile tea, which helps to prevent liver spasms caused by gall bladder-stimulating herbs.

Choline

December 28, 2011 by  
Filed under Database

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Vitamin-like substance

Functions

  • Component of all lipoproteins
  • Lipotropic (helps to remove fat from the liver)
  • Structural role in cell membranes
  • Synthesis of the neurotransmitter acetylcholine

Good food sources

  • Egg yolk
  • Grains
  • Heart
  • Lecithin
  • Liver
  • Nuts
  • Pulses

Deficiency symptoms

  • Fatty liver and liver impairment
  • Possible memory or thought impairment
  • Retarded growth

Preventing deficiency

Choline is relatively low in fruits and vegetables, so those most at risk of choline deficiency (and other deficiencies) are those on long-term ‘fad’ diets such as fruit-only regimes. Choline may also be deficient if liver function is impaired, since a limited amount of choline can be synthesized in the liver, using the amino acid methionine. As with all other nutrients, a wide variety of foods, preferably for the most part unrefined, is the best health protection.

It would be difficult to develop a choline deficiency without also developing a number of other deficiencies.

SUPPLEMENTATION

In research studies, choline supplements have been found to:

  • Foster healing of fatty liver changes in ex-alcoholics
  • Reduce the cholesterol content of bile and increase bile phospholipids
  • Reduce the tremors of tardive dyskinesia, a Parkinson’s disease-like syndrome caused by major tranquillizer drugs used against schizophrenia

Preferred form and suggested intake

The preferred form of choline supplementation is phosphatidyl choline, also known as lecithin. It can be bought in granules and sprinkled on food or in hot drinks. The usual dosage is 1-2 tablespoons per day.

Cautions

Some forms of choline used in medical practice can give the body a fishy odour. Phosphatidyl choline (lecithin) does not, and there is no known unsafe dosage of this form of choline.

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