Vitamin C
Vitamin C (aka. ascorbic acid) cannot be manufactured by our bodies so it must be derived from food or food supplements. Vitamin C is crucial for normal body functioning especially ‘healing’ but it also plays a variety of other key roles in our health including facilitating the absorption of iron. The body is quickly depleted of Vitamin C, a water-soluble molecule, through excessive drinking and smoking.
It is essential in maintaining healthy gums, a topped up immune system (it plays a role in the production of white blood cells or leukocytes) and there is evidence that chronic deficiency is a contributing factor in atherosclerosis, the hardening and deterioration of the inner walls of arteries encouraging plaque formation. As a co-factor, it plays a role in the functioning of at least eight different enzymes.
Vitamin C is an incredibly versatile vitamin; it is actually referred to as a cofactor with crucial roles in at least eight enzyme-based catalytic reactions including collagen synthesis. Deficiency in vitamin C results in scurvy and atherosclerosis. It is found in high concentrations in immune cells and is a natural antihistamine. Its a potent antioxidant and exists in the body as free ascorbic acid as well as its salts depending on ph (acidity-alkalinity) changes. It too is a water-soluble vitamin, best taken in smaller and more frequent doses rather than single large doses. It is not yet entirely clear whether vitamin C and antioxidants, in general, prevent oxidative stress-related diseases and promote health. Vitamin C also facilitates absorption of elemental iron in the gastrointestinal tract.
Many superfoods (previously blogged) are rich sources of vitamin C. Lemons and oranges, and the citrus family, apples, berries, plums, and Acerola are excellent sources of vitamin C and are readily available.
Vitamin C supplements in the active form may at times cause indigestion, so some vitamin C supplements are marketed as buffered C or Ester C, thereby offering the right balance between acidity and alkalinity. The preferred form of vitamin C for ingestion is ‘buffered vitamin C’ or buffered C.
Elderberry Extract
Elderberry juice and extracts contain organic pigments, tannin, amino acids, carotenoids, flavonoids, sugar, rutin, vibronic acid, vitamin A and B and a large amount of vitamin C. It is a popular winter supplement.
It is also mildly laxative, a diuretic, and diaphoretic. Flavonoids, including quercetin, are believed to account for the therapeutic actions of the elderberry flowers and berries. According to test tube studies2, these flavonoids include anthocyanins that are powerful antioxidants and protect cells against damage.
Ginger
Ginger rhizomes are a favourite of oriental kitchens! Ginger offers a spicy, hot, fragranced spice in cooking because of zingerone, scholars, and gingerols which are all volatile oils.
It is consumed as sweets, in tea bags as an infusion, cooked and pickled, or chopped raw. It is also used to treat morning sickness in pregnancy.
The B Vitamins
Although B vitamins were originally misunderstood as being just one vitamin (like vitamin c), they are actually a group of chemically distinct water-soluble molecules that play important roles in cell metabolism and body functions. In general, supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific name of each vitamin, which are Vitamin B1 (Thiamine), Vitamin B2 (niacin or niacinamide), vitamin B5 (pantothenic acid), Vitamin B6 (pyridoxine), Vitamin B7 (Biotin), Vitamin B9 (folic acid), Vitamin B12 (cyanocobalamin or its widely used derivative hydroxocobalamin).
Thiamine plays a key role in energy generation from carbohydrates, nerve functioning and RNA and DNA production and its deficiency results in beriberi. Riboflavin is involved in energy production for the cell’s electron transport chain, the citric acid cycle, and fat break down (beta-oxidation of fatty acids) and its deficiency results predominantly in mucus membrane damage; swollen tongue, angular stomatitis. Niacin is actually two molecules combined (nicotinic acid and nicotinamide) both of which are co-enzyme forms of nicotinamide adenine dinucleotide (NAD) and NAD phosphate (NADP). Their main role is in energy transfer reactions and in the metabolism of glucose, alcohol and fat. NAD itself carries hydrogen and its electrons in the citric acid cycle and NADP is a coenzyme in lipid and nucleic acid synthesis. A deficiency in niacin results in pellagra. Pantothenic acid is involved in the oxidation of amino acid, fatty acid, ketones, cholesterol, phospholipids, steroid hormones, neurotransmitters and antibody synthesis. Pyridoxine deficiency may lead to microcytic anaemia as B6 is a cofactor for heme synthesis, in depression, dermatitis, hypertension, water retention, and high levels of homocysteine. Biotin deficiency is rare and does not ordinarily cause symptoms in adults but may lead to impaired growth and neurological disorders in infants. Multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal. Folic acid deficiency results in macrocytic anaemia and elevated levels of homocysteine. Deficiency in pregnancy can lead to birth defects and for this reason, supplementation is recommended during pregnancy. Vitamin B12 deficiency results in a macrocytic anaemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits. It is most likely to occur among elderly people, as absorption through the gut declines with age; the autoimmune disease pernicious anaemia is another common cause of B12 deficiency. It can also cause symptoms of mania and psychosis and left untreated can result in paralysis.
Because water-soluble B vitamins are eliminated in the urine, they are better taken in small and frequent doses or else they produce transient effects.
Vitamin D
This is variously referred to as cholecalciferol, calciferol and vitamin D is colloquially referred to as the ‘sunshine vitamin’. Vitamin D has recently received widespread publicity presumably because of a long-overdue recognition of the high potential for deficiency here in the UK as it is manufactured in the skin via exposure to sunlight but also through diet and supplementation. Borderline vitamin D deficiency is corrected through injections of cholecalciferol. Vitamin D facilitates calcium absorption, hence the availability of a multitude of products containing both calcium and Vitamin D in the range of potencies. The role of calcium and vitamin D in osteoporosis prevention and bone health is well documented, especially its beneficial effect in combination with biphosphonates like alendronic acid. However, vitamin D also plays a crucial role in maintaining an optimal immune system.
As vitamin D is fat-soluble and excessive intake could result in overdose, a common question has been ‘how much vitamin D is enough?
The Royal College of Paediatrics and Child Health estimates that up to 25% of UK children are Vitamin D deficient, leading to a steep rise in reported cases of rickets (from 183 in 1996 to 762 in 2011), first signs of which are bone and muscle ache along with swelling around the wrist and ribs.
Furthermore, estimates suggest that nearly half of the adult white population and up to 90% of the black and Asian population are thought to be affected by vitamin D deficiency. Earlier this year the Chief Medical Officer for England, Dame Sally Davies recommended all pregnant and breastfeeding women, children aged six months to five years and the over 65’s should take vitamin D supplements.
Vitamin D does not have a ‘recommended daily intake’ like most other vitamins and minerals as it is primarily manufactured by the body rather than consumed in food. The Government advises a daily intake of 10micrograms for adults, and vitamin D drops for babies (unless taking formula) and under-fives.
Echinacea
This beautiful flower found predominantly in eastern and central North America has been the source of much interest. Its medicinal benefits are actually derived from three species, mostly E. purpurea.
There are very many attractive Echinacea-based products on the market in the form of drops, oral liquids, lozenges and tablets and the market for echinacea-based products has blossomed exponentially. Yet, the underlying lack of rigorous scientific evidence has been compelling enough for this ‘alternative natural therapy’ to flourish.
A 2007 study by the University of Connecticut combined findings from 14 previously reported trials examining Echinacea and concluded that Echinacea can cut the chances of catching a cold by more than half, and shorten the duration of a cold by an average of 1.4 days. However, other authors in the Journal of Scientific Review of Alternative Medicine have claimed that the referenced trials lack the similarities necessary to provide definitive results when combined into one report. “If you have studies that measure different things, there is no way to correct for that. These researchers tried, but you just can’t do it. Yet that is what retrospective research of the evidence is what it is all about.
A 2003 controlled double-blind study at the University of Virginia School of Medicine published in the New England Journal of Medicine stated that echinacea extracts had “no clinically significant effects” on rates of infection or duration or intensity of symptoms. The effects held when the herb was taken immediately following infectious viral exposure and when taken as prophylaxis starting a week prior to exposure. In a press release, a manufacturer of Echinacea-related products, calls the study “faulty and inaccurate.” According to this report, none of the three extracts used on the 399 study participants contained all three of the components of Echinacea responsible for its immune-enhancing effects: polysaccharides, alkylamides and cichoric acid. In addition, the standard dosage for dried Echinacea Angustifolia root is normally three grams per day or more and this study used less than one gram.
An earlier University of Maryland review based on 13 European studies concluded that echinacea, when taken at the first sign of a cold, reduced cold symptoms or shortened their duration. The review also found that three of four published studies concluded that taking echinacea to prevent a cold was ineffective.
The European Medicines Agency (EMEA) assessed the body of evidence and approved the use of expressed juice and dried expressed juice from fresh flowering aerial parts of E. purpurea for the short-term prevention and treatment of the common cold and issued the following recommendations:
“It should not be used for more than 10 days. The use in children below 1 year of age is contraindicated, because of the theoretically possible undesirable effect on the immature immune system. The use in children between 1 and 12 years of age is not recommended, because efficacy has not been sufficiently documented although specific risks are not documented. In the absence of sufficient data, the use in pregnancy and lactation is not recommended.“
Cancer Research UK has also stated its considered view on the matter of Echinacea use by people with cancer. It states:
“There is no scientific evidence to show that echinacea can help treat, prevent or cure cancer in any way. Some therapists have claimed that echinacea can help relieve side effects of cancer treatments such as chemotherapy and radiotherapy. But this hasn’t been proved either.“
Zinc
Zinc is an essential trace element, necessary for plants and animals. Zinc is found in nearly 100 specific body enzymes (chemicals which catalyse, facilitate, essential bodily chemical reactions. After iron and it is the only metal which appears in all enzymes classes, an illustration of its abundance and importance.
Yet it has been estimated that zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhoea, contributing to the death of about 800,000 children worldwide per year. Zinc deficiency can cause ataxia, lethargy, sexual disfunction and copper and magnesium deficiency.
Zinc’s medicinal properties date back to the 17th century with the use of zinc poultice to cure skin infections, wounds, and sours. Zinc helps speed up the healing process after an injury. It does so by facilitating the process of healing called cicatrisation. To migrate, endothelial cells need collagenases and plasminogen activator to degrade the clot-forming during the early stages of healing and part of the epithelial cell membrane (ECM). Zinc-dependent metalloproteinases digest basement membranes and ECM to allow cell migration, proliferation and angiogenesis (new cell formation).
Zinc also protects against accelerated ageing of the skin and body muscle; studies differ as to its effectiveness. Zinc deficiency may also have effects on virtually all parts of the human immune system whereby the efficacy of zinc compounds, when used to reduce the duration or severity of cold symptoms, is controversial. A 2011 systematic review concludes that supplementation yields a mild decrease in duration and severity of cold symptoms, conclusive in favour of zinc supplementation during winter.
Although not yet tested as a therapy in humans, a growing body of evidence indicates that zinc may preferentially kill prostate cancer cells. Because zinc naturally migrates towards the prostate gland and because the prostate is accessible with relatively non-invasive procedures, its potential as a chemotherapeutic agent in this type of cancer has shown promise. However, other studies have demonstrated that chronic use of zinc supplements in excess of the recommended dosage may actually increase the chance of developing prostate cancer, also likely due to the natural buildup of this heavy metal in the prostate. Yet, this observation could stand to reason in relation to excessive use of any other nutritional supplement.
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