Sunday 28 December 2014

Ephedra: The Best Weight Loss Herb You Can’t Buy

The ephedra species are tall plants that grow in arid regions of the World. Chinese ephedra (Ephedra sinica) is also called Ma Huang and is the species found in Asia, whereas European ephedra (Ephedra distachya) is the form found in Europe. Other species include Phedra viridis, Ephedra gerardiana, Ephedra nevadensis and Ephedra americana. Ephedra plants contain alkaloids which are believed to be the active ingredients in preparations. The total alkaloid content of ephedra is around 3 to 4 % with 50 to 90 percent of this being the alkaloid ephedrine and the remaining alkaloids comprising pseudoephedrine and norpseudoephedrine. The alkaloid content of other ephedrine species varies with Ephedra nevadensis containing no ephedrine. Ephedra has been used in Chinese medicine for millennia to treat asthma, hay fever, bronchitis arthritis and hypotension. Ephedrine and pseudoephedrine were chemically synthesised in the 1920’s and since then have been used as cold and flu remedies.
Ephedrine and pseudoephedrine are beta adrenergic agonist and in this regard are able to mimic the effects of adrenaline. This puts ephedrine in the same group of drugs as amphetamine, although the effects of ephedrine are much milder than in the case of amphetamine. Ephedrine therefore has a pronounced effect on the cardiovascular system, and in particular is able to increase heart rate and the force of contraction of heart muscle. This explains the ability of ephedrine to treat hypotension. Ephedrine and pseudoephedrine can relax bronchial muscle because there are beta adrenergic receptors in the airway. This is a similar mechanism by which clenbuterol and salbutamol are able to relax the airway. This explains the ability of ephedrine to treat rhinitis, hay fever and asthma. Pseudoephedrine tends to be a better bronchial drug than ephedrine because it has fewer of the cardiovascular and central nervous system side effects. Ephedrine also stimulates the central nervous system giving users a strong motivational desire.
Perhaps the most famous use for ephedra is as a weight loss aid. Clinical studies attest the the effectiveness of ephedra preparations in this regard. Based on its performance in clinical trials it could be argued that there is no better weight loss drug. The ability of ephedra to cause weight loss likely relates to the presence of the ephedrine it contains. Ephedrine is able to stimulate beta adrenergic receptors on fat cells and this causes a breakdown of triglycerides to fatty acids. At the same time, ephedrine stimulates substrate utilisation and the fatty acids are oxidised to produce heat. Estimates from studies show that ephedrine may increase heat production by 40 %, with most of the energy for this being derived from fat. Ephedrine is also an effective weight loss drug because it causes a retention of skeletal muscle that allows the resting metabolic rate to be maintained at a higher level than would normally be possible during weight loss. This is a shame, because ephedra is no longer available for sale in the United Kingdom, despite an excellent safety record..
The thermogenic effects of ephedrine are enhanced by concomitant administration of methylxanthines (e.g. caffeine) and salicylates (e.g. aspirin). Studies involving just isolated ephedrine have shown weight loss effects, but the results from such studies are inconsistent. This likely relates to the fact that the addition of methylxanthines and salicylates is required to get the most thermogenic benefit from ephedrine. Most studies using a combination of ephedrine and caffeine have used roughly ten times the dose of caffeine to ephedrine. For example, if 20 mg of ephedrine was administered the dose of caffeine required for effective synergism is roughly 200 mg. A similar formula is used to optimise the intake of aspirin for a synergistic effect. Therefore 20 mg of ephedrine would be taken with 200 mg of caffeine and 200 mg of aspirin. This regimen is usually repeated 3 times per day, with the last dose being around late afternoon, so that sleep is not disturbed by the pronounced stimulating effect of the ephedrine and caffeine.
RdB

Saturday 27 December 2014

Animal Produce Nomenclature


Bromelain: Anti-inflammatory Compounds

Bromelain is a group of proteolytic (protein digesting) enzymes that are found in high concentrations in the pineapple (Ananas comosus). Bromelain is similar to the sulfhydryl proteases papain from papayas and ficin from figs. Bromelain can be obtained by eating the pineapple fruit, but commercially available supplements are usually made from the stem. Bromelain is present in the fruit to allow softening of the fruit during the ripening process. The bromelain content of various parts of the pineapple plant differs and this reflects the fact that bromelain is a collection of proteolytic enzymes not a single substance. The activity of bromelain (as with all enzymes) is expressed as enzyme units and this gives an idea of the potency of any preparation. Bromelain is bioavailable in humans and can be absorbed to the circulation when taken orally. Animal studies show that around 40 % of administered bromelain is absorbed, with peak absorption occurring 10 hour post ingestion and bromelain remaining in circulation for 48 hours.
Dietary bromelain has been researched for its ability to improve digestion, reduce inflammation, decrease blood platelet aggregation and cause relaxation of smooth muscle. The ability of bromelain to reduce inflammation is thought to occur via multiple mechanisms. In this regard, bromelain may activate proteolysis at sites of inflammation, inhibit the synthesis of proinflammatory eicosanoids, deplete kininogen (a cofactor required in the inflammatory pathway), and the activation fibrinolysis (the breakdown of fibrin in the clotting system that would normally encase the site of injury and block blood flow and cause oedema) through conversion of plasminogen to plasmin. The ability of bromelain to inhibit and reduce the inflammatory response to injury is well studies in the nutritional literature. It is the ability of bromelain to reduce inflammation that makes it useful in cases of soft tissue injury as might occur in athletes during sporting events.
The anti-inflammatory effects of bromelain make it a useful treatment for arthritis. Both rheumatoid and osteoarthritis respond positively to administration of oral bromelain, as demonstrated in clinical studies. In combination with curcumin (another potent anti-inflammatory agent) bromelain is able to reduce the requirement for corticosteroids in cases of severe arthritis. Bromelain may also be able to increase plasma and tissue levels of particular antibiotics. This may relate to the fact that bromelain itself possesses antibiotic activity and therefore potentiates the action of antibiotic drugs by providing synergism. Animal studies also suggest that bromelain has an anti-cancer activity. Interestingly when the proteolytic activity of bromelain is removed through denaturing, an anti-cancer effect in the preparation is still evident, suggesting that components other that the proteolytic enzymes within bromelain are responsible for this effect. Bromelain is taken on an empty stomach for best absorption or with food as a digestive aid.
RdB

Sunday 21 December 2014

The Cardioprotective Effects of Walnuts


Whole Grain Versus Refined Grains

Evidence suggests that consumption of whole grain foods is associated with protection from Western lifestyle diseases. In contrast, consumption of refined grains increases the risk of a number of major Western diseases including obesity, cardiovascular disease, type 2 diabetes and cancer. Because of the different health outcomes between whole grains and refined grains, it is worth considering the nutritional differences between the two forms of cereal grain in order to assess the reasons for the discrepancy in health outcomes. Generally whole grains retain the original composition of the cereal grain while refined grains have certain components removed during processing. Grains possess an outer bran layer, an inner endosperm later and a germ layer. The bran is a layer between the outer seed coat and the aleurone layer of the endosperm. The endosperm is a starchy layer within the aleurone layer and within the endosperm in the germ later. The germ is the embryo for sprouting a new plant and the endosperm is a source of energy for this growth until photosynthesis can proceed.
Processing the grain tends to remove the outer seed coat, the bran and the germ layers. This is done for taste reasons, as white refined flour from cereal grains is prefered by the Western palate. In addition, white flour has a longer shelf life compared to its whole grain equivalent, and this is beneficial for the food industry. This leaves the starchy endosperm as the main component of white refined flour. The bran, germ and aleurone layers contains most of the fibre in the grain and also many of the vitamins and minerals and other nutrients. Removing the fibre is problematic because it may increase the rate of digestion of the starchy endosperm layer, and this can increase the absorption rate of the subsequent glucose considerably. Refined grains therefore tend to produce greater rises in blood sugar when compared to their whole grain alternatives. Over time the exaggerated blood sugar responses caused by fibreless refined grains can cause insulin resistance and this contributes significantly to disease.
However, the refining of the micronutrients from cereal grains can also cause health problems. The mineral chromium for example is required for correct function of the insulin receptor. Without chromium as a cofactor, the insulin receptor becomes insensitive to the hormone insulin and this causes increases in blood sugar levels and metabolic dysfunction. Grains are also a good source of antioxidants, and refining the bran, germ and aleurone layers from grains removes most of their antioxidants. However, whole grains cereals might also contribute to ill health if their processing results in a flour that is too fine. This is because the outer layers of fibre and intact cell walls might be required to provide the beneficial glycaemic effects of whole grains. This certainly explains the beneficial glycaemic effects of rolled oats, grains that retain not only their original composition, but also much of their structure. As will all plants foods eating them in an as unprocessed form as possible may therefore be the most advantageous situation for health.
RdB

Saturday 20 December 2014

The Pharmacological Effects of Niacin


Coenzyme Q10: The Cardioprotective Nutrient

Coenzyme Q10 is an essential part of the mitochondrial respiratory chain. Every eukaryotic cell therefore needs coenzyme Q10, hence its alternative name ubiquinone. Coenzyme Q10 functions as an electron acceptor in the mitochondria and in this way is involved in the transfer of electrons from the energy producing pathways of glycolysis and the citric acid cycle to molecular oxygen, leading to the production of water and carbon dioxide. In this process ATP is produced and coenzyme Q10 is therefore pivotal in energy production. Coenzyme Q10 is synthesised endogenously in humans and so on first sight it might appear that dietary coenzyme Q10 is not important. However, since its discovery in 1957 by Crane and his coworkers, it has been shown repeatedly that dietary coenzyme Q10 does have particular health benefits in certain subgroups of the population. In particular high doses of supplemental coenzyme Q10 may be beneficial as an antioxidant as well as in the treatment of cardiovascular disease and periodontal disease.
Coenzyme Q10 is known to possess antioxidant ability in humans, and in this regard is effective at preventing lipid peroxidation. Coenzyme Q10 can work to recycle vitamin E (here) and thus is able to protect cell membranes from oxidation. Evidence suggests that ageing can reduce the synthesis of coenzyme Q10. As levels of coenzyme Q10 drop, the most metabolically active tissues are affected first. Because the heart is very metabolically active, a low production of coenzyme Q10 can cause heart problems. Supplemental coenzyme Q10 has been shown to be beneficial at protecting from the symptoms of cardiovascular disease, with particularly efficacy shown against congestive heart failure. This makes sense, because congestive heart failure is seen as a condition caused by an inability for the heart to pump correctly and this may relate to low energy levels in heart tissue muscle. As well as congestive heart failure, coenzyme Q10 has been shown to be effective against high blood pressure, mitral valve prolapse and angina.
Another use for supplemental coenzyme Q10 is in the treatment of periodontal disease. Poor oral hygiene can allow a buildup of bacteria and plaque within the mouth and this leads to inflammation that causes a receding gum line. Eventually this progresses to periodontitis and the the teeth become inflamed because pockets of bacteria spread to below the gum line. As the bone that hold the teeth is destroyed, the teeth can fall out and cause irreversible damage. Consensus is that oral hygiene plays an important role in the aetiology of periodontal disease. However, if oral hygiene is improved, the gum tissue requires large amounts of energy to heel. This makes coenzyme a useful supplements to take to repair the damage from receding gums. Studies show that coenzyme Q10 can reduce inflammation in cases of periodontal disease. Around 50 to 200 mg of coenzyme Q10 is used to treat cardiovascular disease and periodontal disease, but lower doses can still provide significant antioxidant protection from oxidative stress.
RdB

Sunday 14 December 2014

Get Rid Of Cellulite: Gotu Kola

Centella asiatica or gotu kola is a water loving flowering plant native to India, parts of Asia, Australia and Madagascar. Traditionally the whole plant can be used medicinally as a treatment for various vascular conditions. Gotu kola has been extensively studied for its effects on vascular tissue and from these studies a number of triterpenoid compounds including asiatic acid, madecassic acid, asiaticoside and madecassoside have been isolated. However differences in the chemical compositions of plants from various regions have been observed. Standardised extract of gotu kola tend to come from those plant grown in Madagascar and typically contain around 30 % asiatic acid, madecassic acid and asiaticoside, as these has been identified as the primary active constituent of the plant. Levels of madecassoside in standardised extract may only be around 2 %. Other compounds present in extracts of gotu kola include quercetin and kaempferol and the essential oils camphor and cineole.
Gotu kola has been used traditionally as an internal and external medicine for the treatment of various conditions. However, of particular interest gotu kola can be used as a treatment for vascular disorders and modern research supports traditional herbalism in this regard. The ability of gotu kola to improve the condition of vascular tissue is likely due to its wound healing effects. This healing process likely includes a stimulation of hair and nail growth, the development and maintenance of blood vessels into connective tissue, increase mucin, hyaluronic acid and chondroitin sulphate production, an increase in the tensile strength of the dermis, and an increased keratinisation of the dermis through a stimulative effect on the germinal layer of the skin. As a result of these physiological effects extracts of gotu kola are beneficial at treating burns, cellulite and disorders of the veins. The ability of gotu kola to improve cellulite in women has been demonstrated in properly conducted clinical trials, with around half of all subjects showing positive improvements in their condition.
RdB

Saturday 13 December 2014

Post Workout Nutrition


Antioxidant Defences: Get Your Cysteine

Glutathione is a tripeptide synthesised from cysteine, glutamic acid and glycine. Glutathione is the primary water soluble antioxidant in both animal and plant tissues and in this role it protects cells from damage by oxidative stress. Glutathione can function as an effective water soluble antioxidant because of the presence of a sulphur group in its structure. This sulphur can donate a hydrogen to reduce other compounds, and in doing so becomes oxidised itself. Studies show that glutathione levels are associated with health and so chronic oxidative stress than can deplete cellular levels of glutathione may be the underlying cause of many diseases of Western origin. Physical exercise is also able to deplete cellular stores of glutathione. Generally if enough rest is provided between training sessions glutathione stores recover and may even improve through supercompensation. However, chronic overtraining that provides inadequate recovery periods may cause long term depletion of glutathione stores and this may explain the disease associated with the stress of exhaustive physical activity.
Antioxidants in the diet may be able to boost cellular levels of glutathione. This relates to the way antioxidants interact. Dietary intakes of vitamin C for example have been shown to spare cellular glutathione and thus increase tissue levels of glutathione. Another way to increase cellular levels of glutathione is to increase dietary intakes of the amino acid cysteine. Cysteine is the rate limiting amino acid for glutathione synthesis and so poor glutathione status in combination with inadequate cysteine in the diet retards the synthesis of glutathione and cellular levels drop. During periods of chronic oxidative stress, cysteine may become conditionally essential due to its role in the synthesis of glutathione. One way to increase dietary intakes of cysteine is by taking the supplement N-acetyl-L-Cysteine (NAC). Supplements of NAC have been shown to be effective at promoting glutathione synthesis. Another way to boost cellular glutathione is to increase intakes of dietary proteins that are high in cysteine. Whey protein is particularly high in cysteine and thus may replete cellular levels of glutathione.
RdB

Sunday 7 December 2014

Kava: The Best Anxiety Cure?

Kava (Piper methysticum) is a perennial shrub that belongs to the pepper family. It is recognisable by its 5 to 10 inch long heart shaped leaves. However, while the visible parts of the kava plant are interesting from a botanical point of view, nutritionally it is the roots of the plants that can be used medicinally. The roots of the kava plant are thick, tuberous and knotty and can be extensive. The roots by dry weight contain around 45 % starch, 12 % water, 3.5 % simple sugars and 3.5 % protein. In addition the kava root contains around 3.5 % minerals, most of which is potassium. The origins of the kava plant are not known, but it is thought to have been spread through the South Sea Islands by Polynesian explorers in canoes. Kava drinking ceremonies are traditional amongst the Oceanic people (Pacific Islanders) of islands such as Fiji, Samoa and Tonga. These kava ceremonies still form part of the tradition of these islands.
Kava is traditionally used as a treatment for anxiety, and it is believed that the active ingredients that provide some of the anxiolytic effect of kava are chemicals called kavalactones. However, as crude extracts of kava may have better effects against anxiety compared to isolated kavalactones, is is likely that other components within the roots of the kava plant contribute to the medicinal properties. Drinking kava tea made from a decoction of the roots in hot water provides a feeling of contentment and relaxation. Most pharmaceutical anxiolytic drugs work by binding to receptors of the inhibitory neurotransmitter GABA. This then decreases neuronal excitation causing a relating effect. However, kavalactones may work via an alternative route. Animal studies for example show that kavalactone alter receptor domains, and are not able to bind to the GABA receptor. Clinical studies using standardised extracts of kavalactones containing D, L-kavain (a purified kavalactone) have proven effective at treating anxiety in human subjects.
Kavalactone may actually have an effect on the limbic system of the brain, the primitive brain that is thought to be the initiator of emotional feeling. In addition, unlike pharmaceutical drugs, kava does not lose effectiveness over time, and is not associated with side effects at reasonable doses other than the ability to induce sleep (which is not really a side effect). Very high doses of kava over prolonged periods can cause dry skin on the hands and feet, something that is reversible on cessation of kava. Kava can also reduce the sensation of pain, but it does not bind to opioid receptors and so again the mechanisms of action is not clear. The kavalactone content of kava root varies between 3 and 20 percent, and this may affect the neurochemical effects seen. While tablets are available containing kavalactones, it is generally recommended that the whole root is consumed due to the possible anxiolytic contribution of other components in the root.
RdB

Saturday 6 December 2014

Dandelion: Diuretic and Liver Tonic

The name dandelion comes from the French for lions tooth (dent de lion). This is in reference to the jagged tooth like leaves that characterise the dandelion plant (Taracum officinale). Generally, gardeners think of dandelion as a weed on account of its aggressive growth into lawns and borders. However, traditionally dandelion is a very widely used medicinale herb and the leaves of dandelion are also used nutritionally to add flavour to salads. Historically, the greeks, Arabs and English have all used dandelion as a medicine, although as trade routes flourished the use of dandelion became more widespread. Its current availability as tablets and decoctions means that the pharmacological properties of dandelion can be obtained without the need to harvest the plant directly as was the traditional method. However, nutritionally the dandelion plant can still be enjoyed fresh from the garden, with its lush green leaves making an excellent salad base. The traditional viewpoint is that dandelion leaves and roots are diuretics and liver tonics.
Dandelion is a rich source of phytochemicals including the terpenoids taraxerol, taraxacin, lactucin and taraxasterol. Dandelion also contains chlorogenic acid and caffeic acid, two antioxidant compounds also present in the coffee bean. Phytosterols are present in the dandelion plant including sitosterol, campesterol, taraxasterol and stigmasterol. Dandelion also contains the flavonoid luteolin as glycosides, as well as high concentrations of potassium, carotenoids and vitamin C. In fact dandelion is particularly rich in potassium (~300 mg per 100 grams), and is often therefore used by herbalists to reverse low potassium levels. The root also contains sesquiterpene lactones and taraxoside, that give the root its bitter taste. The different nutritional properties of the root and leaves are interesting because the leaves may possess better diuretic properties than the root. Studies on rats show dandelion leaves are as effective as the prescription diuretic furosemide at causing diuresis.
The exact reason for dandelions diuretic effects are not fully understood, but it is likely that a number of the components of the leaves are responsible for this action. Dandelion can also improve the liver function through improving the condition of the gallbladder. In this regard dandelion has a choleretic effect (increases bile flow) and a cholagogic effect (increases the contraction of the bile duct). In addition, traditional herbalism has used dandelion as a digestive tonic. Dandelion may stimulate the appetite in cases where appetite has fallen, reduce abdominal bloating and cramps, as well as stimulate the flow of hydrochloric acid from the stomach. As well as being an important herb in its own right, dandelion is useful to combine with nettle for its diuretic effects or with milk thistle for its general liver tonic and digestive effects. Supplements or eating the whole plant should produce similar effects, although whole herb preparations are recommended because the active ingredients have not been identified.
RdB

Sunday 30 November 2014

An Apple a Day Keeps The Doctor Away

Fruit consumption is associated with improved health outcomes. In particular those who consume more fruit have been observed to have lower rates of Western lifestyle diseases such as cancer, cardiovascular disease and obesity. The reason that fruit is beneficial to the health is not known, but likely relates partly to the nutrient content of the fruit and partly because consumption of fruit tends to be at the expense of other foods that may be less healthy. Apples have been extensively researched for their health effects and the findings from such studies support the contention that they are protective of disease. Apples like most fruits contain sugars, but the sugars content of apples is low, and apples do not cause the stimulation of large quantities of insulin. This likely relates to the water and fibre content of the fruit, as well as the type of sugar present. The water and fibre in apples limits the amount of sugar that can be ingested because the water decreases the concentration of the sugars and the fibre provides bulk which slows ingestion rates. The sugars in apples are also not rapidly absorbed. The pectin may also have other beneficial health effects such as decreasing postprandial glycaemic effects of other foods, lowering cholesterol levels, and stimulating the growth of beneficial gut bacteria.
Apples are also a good source of polyphenols. Polyphenols are plant metabolites that are used for host defence. Plants use polyphenols to protect from environmental damage including ultraviolet light, parasites and pests. When we ingest apples, we consume a range of polyphenols that have been shown to be bioavailable. The main polyphenolic substances found in apples include flavonoids, hydroxycinnamates and chalcones. The flavonoids in apples include quercetin and epicatechin, both of which have been shown to possess beneficial health effects. Epicatechin is also present in green tea and may partly responsible for the benefits of drinking green tea. Quercetin is a common flavonoid in many fruits and vegetables and has been shown to cause anti-cancer effects in human cells. Polyphenols may be beneficial to human health because they have antioxidant effects, and in this respect can reduce inflammatory. Polyphenols also possess anti-microbial, anti-cancer and cardioprotective effects. The polyphenolic and fibre content of apples is concentrated in the skin and so consuming the skin with the rest of the pulp is an important nutritional consideration if health is a concern. Other beneficial substances in apples include the phenolic phloretin, as well as vitamin C and minerals.
RdB

Saturday 29 November 2014

Biochemical Individuality


The Niacin Paradox

The niacin paradox describes the paradoxical situation that results from some important sources of niacin being low in actual niacin. This arises because while some foods are low in niacin, they are high in tryptophan, itself being able to be converted into niacin through the kynurenine pathway. The observation that rats could synthesise niacin, and that the synthesis of that niacin was related to the protein content of the diet lead some researchers to investigate the effects of amino acids on niacin metabolism. From this research it was found that administration of tryptophan to rats increased the urinary excretion of niacin. The realisation that administration of tryptophan was effective at reversing and preventing pellagra confirmed that niacin was likely synthesised from tryptophan. Initially it was thought that the tryptophan to niacin conversion may occur in the intestinal tract through the action of bacteria, but experiments administering injections of tryptophan showed immediate elevations of niacin metabolites.
Around 10 % of dietary tryptophan may be used for niacin synthesis. Niacin is therefore technically not a vitamin as it can be synthesised endogenously if adequate tryptophan is present in the diet. The niacin requirement in man is likely related to the total calorie intake, with higher energy intakes requiring larger intakes of niacin. A figure of around 5 mg of niacin per 1000 kcal is suggested to be the minimum required to prevent pellagra, assuming more than 2000 kcal in total are consumed. The realisation that some foods provide their niacin content as tryptophan has lead some to suggest that instead of absolute niacin concentrations, the niacin equivalents should be used. As a rough approximation the tryptophan concentration of protein is 1 %, and around 1 mg of niacin is obtained from 60 mg of tryptophan. From these figures a rough approximation of the niacin equivalents of food can be made. Some foods such as beef are high in tryptophan and niacin, and as a result are excellent sources of vitamin B3.
RdB
Horwitt, M. K., Harper, A. E. and Henderson, L. M. 1981. Niacin-tryptophan relationships for evaluating niacin equivalents. American Journal of Clinical Nutrition. 34: 423-427
Goldsmith, G. A. 1958. Niacin-tryptophan relationships in man and niacin requirement. American Journal of Clinical Nutrition. 6: 479-486

Sunday 23 November 2014

Gugulipid

The mukul myrrh tree (Commiphora mukul) is a one meter tall thorny tree found in the Middle East and India. A yellowish resin called guggulu (gum guggul) derived from the tree can be collected and used for medicinal purposes. This guggulu is processed with solvents to remove the gum carbohydrate fraction which is not medicinal but can possess toxic effects in animals. The remaining gugulipid fraction produces neutral, acidic and basic components. The most important of these is the neutral component, which makes up around 98 % of the total gugulipid fraction and contains two groups of chemicals. A ketonic group includes a number of phytochemicals called guggulsterones, plant sterols with cholesterol lowering properties. A non-ketonic fraction includes phytochemicals including diterpene, lignans and fatty acids. The other important component of gugulipid is an acid component which makes up about 4 % of the final product and this contains a number of anti-inflammatory compounds including the non aromatic acid ferulic acid and a number of phenolic and non-phenolic aromatic acids.
Standardising the extract of gugulipid to contain 50 mg of guggulsterones per gram produces the most beneficial health benefits. Extracts of gugulipid have been researched primarily for their ability to modulate plasma lipoprotein levels. In particular standardised extracts of gugulipid can lower plasma levels of low density lipoprotein (LDL) cholesterol and very low density lipoprotein (VLDL) cholesterol (also called plasma triglycerides), as well as raise levels of high density lipoprotein (HDL) cholesterol. As high levels of LDL and VLDL and low levels of HDL are associated with cardiovascular disease, gugulipid may be cardioprotective. Cholesterol can be lowered by three 25 mg doses of guggulsterones from standardised gugulipid extract per day. The anti-inflammatory effects of gugulipid has also been extensively researched with studies showing that the standardised extract of gugulipid can be as effective as hydrocortisone, phenylbutazone or ibuprofen at reducing the symptoms of chronic inflammation. The amount required for an effective anti-inflammatory effect likely depends on the severity of the inflammation.
RdB

Saturday 22 November 2014

Do Low Sodium Diets Lower Blood Pressure?


Protect Your Liver: Milk Thistle

Milk thistle (Silybum marianum) is a three foot high thistle that grows in rocky parts of Western Europe. The reddish purple flowers and shiny prickly leaves give it an easily recognisable appearance. Milk thistle is interesting nutritionally because it contains a number of bioactive phytochemicals that may have useful health properties. In particular, milk thistle contains a number of flavonolignans (phenolic compounds composed of part flavonoid and part lignan) that include silybin, silidianin and silychristin. These compounds are present in the seeds and leaves, but are found in their highest concentrations in the fruits. Collectively these compounds are referred to as silymarin, and they can be found in standardised extract that have been shown to have liver protecting effects. This protective ability of silymarin on the liver relates to the ability of flavonolignans to prevent the mechanisms by which liver damage can be induced. It is thought that this damage results from the generation of free radicals which increases the oxidative stress on hepatic tissue.
The antioxidant effects of silymarin have been well reported and as well as a direct antioxidant effect, silymarin also increases cellular levels of glutathione, presumably through its ability to spare reduced glutathione (GSH). In addition silymarin is an inhibitor of the enzyme lipoxygenase, an enzyme responsible for the transfer of oxygen molecules to long chain polyunsaturated fatty acids in the membranes of cells. This reaction yields leukotrienes, eicosanoid hormones that have pro-inflammatory effects. Milk thistle therefore has potent anti-inflammatory effects and can protect the liver from the deleterious effects of leukotrienes. The beneficial effects of milk thistle have been demonstrated in a number of animal models using chemically induced liver damage (using the death cap mushroom Amanita phalloides). Death Cap mushroom causes severe liver damage and death is induced in around 30 % of those who ingest it as a result of liver failure. Silymarin extract can counteract the poisonous effects of this mushroom and prevent the deaths of animals in 100 % of cases.
Another benefit of milk thistle is the its ability to increase protein synthesis rates in hepatic tissue. In this way milk thistle can rebuild damaged liver tissue and thus repair diseased tissue. Many studies have shown that milk thistle supplements containing silymarin are effective at treating patients with damaged livers such as might occur in cirrhosis, chronic hepatitis and both alcoholic and non-alcoholic fatty liver disease. Silymarin may also have beneficial effects at increasing the solubility of bile, and in this way may be a useful treatment and prevention of gallstones, which are largely caused by the insolubility of bile leading to obstructions in the gallbladder. Milk thistle is available as a supplement and the best supplements are standardised for around 70 to 80 % silymarin. Milk thistle can also be purchased as a tea and consumed in its whole herb form, but it makes sense to obtain a standardised extract because it is known that the presence of silymarin is required for its liver protecting effects.
RdB

Wednesday 19 November 2014

Whole Olives

Olive oil has been researched with regard its beneficial effects on cardiovascular disease. While polyunsaturated fatty acids do appear to show some protective effects against cardiovascular disease, the cardioprotective effects of the monounsaturated fatty acids that predominate in olive oil are less clear. In fact it appears from research that most of the cardioprotective effects of consuming olive oil comes not from the fatty acids but the phytonutrients within the oil. These phytonutrients survive the oil processing steps and are then consumed along with the oil. That extra virgin olive oil is more beneficial than non-extra virgin olive oil supports this theory because extra virgin olive oil contain higher concentrations of these plant chemicals due to its less refined nature. Based on the logic that it is the phytonutrients within the olives rather than the oil itself that is cardioprotective, consuming whole olives as part of a high quality diet makes sense from a health perspective. Olives are likely protective of cardiovascular disease because they contain high levels of antioxidants.
The olive tree (Olea europaea) produces fruits which we call olives. Olives are commercially available as both green and black fruits, but they are infact the same produce at different degrees of ripeness. As the olive ripens it passes from green to black, and as such black olives are fully ripe while green olives are slightly unripe. Olives have a fat content of around 20 to 35 %, the oil containing high concentrations of the omega-9 fatty acid oleic acid (OA, C18:1 (n-9)). As with all plant material containing fatty acids, olives are also a good source of vitamin E, as this is used by the plant to protect the oils from rancidity. In addition, olive contain a number of phytochemicals including the phenolic terpene compounds oleuropein, tyrosol and hydroxytyrosol. These phytochemicals are bioavailable in humans and may have antioxidant effects. In particular the phenolic compounds in olives may prevent oxidative stress in the epithelial cells of arteries and this may in turn prevent the development of endothelial dysfunction and high blood pressure. Olives also contain melatonin, a signal molecule that induced sleep and relaxation in humans.
RdB

Monday 17 November 2014

A Word On The Potato

The potato (Solanum tuberosum) is a plant that belongs to the nightshade family that also includes tomatoes, aubergines and bell pepper. There are hundreds of varieties of potato, but in reality the large potato manufacturing countries rely on a handful of varieties to maintain supply. The potato is important nutritionally because it contributes such a large part to the energy needs of the population of the World. Because a small portion of land can produce such a large crop of potatoes, they were historically important as a food crop for resource poor individuals. Potatoes can be eaten at full maturity or before this time, the latter often being referred to a baby potatoes. In the United state almost half of the potatoes are sold to food manufacturers to be turned into chips (french fries) and obviously in this form the potato is not a good food choice. However, the potato if prepared well is a good source of nutrients and can be consumed as part of a healthy diet.
The fibre in potatoes is also nutritionally interesting because it is located on the outside of the vegetable as a tough outer skin. Peeled potatoes therefore lose much of their fibre content and this can detrimentally affect the glycaemic index of the potato. Nutritionally potatoes contain a wide range of micronutrients, the exact content of which can vary somewhat depending on growing conditions. Generally, potatoes can contain potassium, vitamin B6, niacin and pantothenic acid. Potatoes are also a good source of vitamin C and this stems not from a high content, but because we eat some many potatoes. As with the fibre, most of the nutrients in potatoes are located in the skin and so eating potatoes whole is recommended. The protein content of the potato is moderate with similar levels to rice or corn, but potatoes do contain good amounts of lysine, an amino acid that is lacking from grains. Combining potatoes with grains can therefore improve the amino acid profiles of grains.
RdB

Sunday 16 November 2014

More On Legumes


The Betaine Choline Link

Betaine and choline are closely related compounds from a structural and functional perspective. Betaine is also called trimethylglycine and choline is also called tetramethylglycine. Both compounds function as methyl donors, and when choline donates a methyl group it becomes betaine. A further donation of a methyl group results in the compound dimethylglycine. One important role for betaine is the conversion of homocysteine to methionine, a process that requires methylation of the homocysteine molecule, the methyl group being donated from betaine. An alternative methylation pathway for homocysteine exists and this required the folic acid derived methyltetrahydrofolate molecule donating a methyl group in a reaction catalysed by the vitamin B12 dependent enzyme methylenetetrahydrofolate reductase. Folic acid, vitamin B12 and betaine are therefore integral in the maintenance of low cellular levels of homocysteine.
As high levels of homocysteine in the cells leads to raised plasma levels of homocysteine, and raised plasma levels of homocysteine are associated with cardiovascular disease, betaine, vitamin B12 and folic acid deficiencies increase the risk of cardiovascular disease significantly. Because dietary choline can be converted to betaine, and because cellular methionine levels increase following administration of high amounts of dietary choline (possibly due to increased synthesis from homocysteine), choline may also be protective of cardiovascular disease at high intakes. Choline is usually classed as a member of the B group of vitamins, and although it can be manufactured in the body, it is officially recognised as an essential dietary nutrient. Choline may also have other protective effects against cardiovascular disease, because it is required for the metabolism of fats from the liver, and without choline fatty acids accumulate in the liver causing metabolic dysfunction.
RdB

Saturday 15 November 2014

Pepper: More Than Just A Condiment

Black pepper (Piper nigrum) is one of the most widely used seasonings in the Western world, surpassed only by salt. The pepper plant is indigenous to India where its use can be traced back to early human history. In Greece pepper was traded as a currency and commodity, such was it prized by the Greeks. Pepper, like salt was popular because it could hide the taste of unfresh food before refrigeration and also because it could improve the taste of bland food. One quarter of the spice production in the World is accounted for by pepper, which grows as a round peppercon on the pepper plant. Black pepper can be refined with the outer black husk being removed prior to milling, and this leaves just the white inner seed layers that have a more aromatic taste. In addition, peppercorns can be picked in an unripe condition and then pickled producing green pepper. The taste of green pepper is again different and in this regard has a more herb like taste.
Black pepper is traditionally used to treat digestive disorders because of its ability to increase stomach acid production and this is able to improve the digestive process. Black pepper also has calmative, antibiotic, diuretic and diaphoretic properties than can make it useful as a general tonic. The high content of antioxidants also make black pepper a generally healthy food against conditions characterised by systemic oxidative stress, such as metabolic syndrome, obesity and cardiovascular disease. Piperine is an active component in pepper which may increase the absorption of certain nutrients (although care should be made when interpreting such studies: here). Piperine may also have thermogenic properties and be able to enhance liver detoxification rates for particular chemicals. The best way to use pepper is by grinding whole peppercorns as this allows the nutritional content to remain fresher for longer.
RdB

Thoughts on Coffee


Friday 14 November 2014

Sunflower Seeds: Not just for The Birds

The sunflower (Helianthus annuus) has a very distinctive flower with amazing geometric patterns. In terms of human nutrition, it is the grey and black seeds of the sunflower plant that are of interest. Sunflower seeds make great bird food because they are a good source of oils and nutrients. However, their nutritional content also makes them a useful addition to any high quality human diet. Sunflower seeds are a rich source of the essential fatty acid linoleic acid (C18:2 (n-6)) and along with this oil they also contain high amounts of vitamin E to protect the delicate fatty acids from rancidity. Sunflower seeds are often turned into sunflower oil and this oil is often refined to produce odourless tasteless supermarket oils through application of high heat and pressure conditions. Such oils are detrimental to the health because they contain oxidised fatty acids. However unrefined virgin sunflower oil contains many of the nutrients in the original seeds and can therefore provide many of the same health benefits.
Minerals in sunflower seeds are dependent on the soil conditions in which the plants are grown because the absence of particular minerals from the soil precludes them from incorporation in the plant tissues. However, in optimal conditions they can be good sources of magnesium, phosphorus, copper, iron and selenium. The vitamins in sunflower seeds include vitamin B1, pantothenic acid and folic acid. Although sunflower seeds are a good source of protein, their high fat content precludes them from contributing significantly to protein intake without a concomitant large increase in fat content. The carbohydrate content of sunflower seeds is generally half that of protein, which in turn is half that of the fat content. Because sunflower seeds are a good source of the omega-6 essential fatty acid linoleic acid, they can contribute to fighting inflammation. However, this can only occur if the omega-6 to omega-3 fatty acid ratio remains at around 1 to 3.
RdB

Saturday 8 November 2014

Pumpkins

Halloween is a time when pumpkins become available in the shops and people buy them to carve ornate decorations. However, few consider the nutritional value of the pumpkin during this process. The pumpkin (Cucurbita pepo) is a type of winter squash which means it is part of the Cucurbitaceae family. The pumpkins used for decorations are generally not eaten and it is the smaller varieties such as the small sugar pumpkins that are consumed. Winter squashes are a great source of carotenoids which give them their red, orange and yellow colours. However, they are also rich in vitamin C, folic acid, vitamin B1, vitamin B6, niacin, pantothenic acid, potassium and dietary fibre. The nutty seeds not only have a distinctive taste, but also a distinctive nutritional profile that makes them a great addition to any high quality diet. Native Americans were renowned for eating pumpkin seeds and they also used them in their medicines. It was from the Indians that the English settlers acquired the seeds before introducing them to Europe.
Pumpkin seeds contain high levels of essential fatty acids, zinc and phytosterols that make them an effective nutritional product for maintaining prostate health. It is thought that the phytosterol beta-sitosterol blocks the conversion of testosterone to dihydrotestosterone in humans. As the latter is associated with prostate enlargement, pumpkin seeds may be able to inhibit this process. In fact studies using pumpkin seed oil and isolated beta-sitosterol show they both confer health benefits to the prostate. It is likely that whole seeds have the same effect. The seeds of pumpkins are also rich sources of vitamin A, vitamin B1, vitamin B2, niacin, and also contain protein and monounsaturated fatty acids. Because of the high essential fatty acid content of pumpkin seeds it is important to ensure that they are stored in a cool dry environment and eaten as soon as possible after exposure to air. This prevents the fatty acids turning rancid, a process that can actually initiate disease through the generation of oxidative stress.
RdB

Saturday 1 November 2014

Are Peanuts A Red Wine Alternative?

Red wine has been shown to confer certain health benefits. In particular, red wine may protect from the development of cardiovascular disease. The reason for this is not fully understood, but it it known that ethanol (alcohol) is able to decrease the risk of a heart attack for around 24 hours following consumption, and so this may partly explain the cardioprotective effects of red wine. However, red wine is also a good source of a group of phytochemicals (plant chemicals) called polyphenols. One polyphenol in red wine that has been researched for its cardioprotective effect is a resveratrol, a phytochemical from the stilbene family. Resveratrol is a strong antioxidant that is bioactive in humans, and it may protect from cardiovascular disease through its ability to prevent oxidation in the blood vessels. In addition, resveratrol may confer protection from cancer as some evidence suggests that is able to inhibit the growth of new blood vessels that are required for the growth of tumours, a process called angiogenesis.
Red wine may therefore reduce the risk of two Western lifestyle diseases, namely cardiovascular disease and cancer. However, some cannot drink red wine for various reasons and therefore such individuals might think they have to miss out on the benefits of resveratrol. However, other sources of resveratrol are available, one particularly good source being peanuts. Studies have shown that the risk of a heart attack drops by around 20 % with just one month of consuming peanut butter or whole peanuts in those consuming a Western diet. The reason for this is not clear but other research has shown that peanuts are able to favourable alter the low density lipoprotein (LDL) to high density lipoprotein (HDL) ratio and this in turn is known to lower the risk of cardiovascular disease. Peanuts are not actually true nuts (tree nuts) but are pulses that come from plants in the legume family. Studies show that many legumes are cardioprotective and therefore it is not surprising that peanuts also share this effect.
Dr Robert Barrington’s Nutritional Recommendation: Red wine is a great drink to share socially and when consumed in moderation can confer significant health benefits. However, some of the benefits of red wine can be obtained from other foods. Peanuts seem to be a good source of antioxidants and this may explain their cardioprotective effects. Whole unshelled peanuts provide the best nutrition because the shells protect the seeds inside from oxidation and this in turn stops the fatty acids from going rancid.
RdB

Can You Overeat High Quality Foods?


Saturday 25 October 2014

The Two Best Natural Testosterone Boosters

Testosterone is an important hormone for muscle growth and as a result athletes are often interested in optimising levels to improve physical performance and body composition. There are a number of substances that are available as supplements that manufacturers claim to be able to boost testosterone. Such substances include L-aspartic acid, ashwagandha, horny goat weed, royal jelly, tribulus terrestris, ginseng, maca, DHEA and a myriad of other substances. Often scientific studies are cited to support the beneficial testosterone boosting effects of such supplements and these can seem convincing. However, when we delve deeper into the supporting literature we often see that such studies are performed on animals, use unrealistically high doses, are performed on men with sexiual dysfunction, or are simply cell experiments. To be able to ascertain if these substances are really beneficial we should ask two questions. Do the substances raise testosterone levels in healthy humans? And does this increase in testosterone translate into an increase in the amount of skeletal muscle in the subjects?
The answer to both of these questions is usually not so clear cut. Often the testosterone increases are given as relative values, that can appear large, but are in fact of no real world significance. In addition, there are very few studies that show actual muscle building effects of these testosterone boosters. So if you want to boost testosterone to build muscle what are the best options? Well the tried and tested way to boost testosterone to cause skeletal muscle is based on lifting heavy weights and eating a high animal protein diet. These two strategies will cause far more muscle growth that any supplement available on the market and are backed by research done on healthy adults in peer reviewed journals. Lifting heavy weights causes large increases in testosterone as this is the primary way the body will adapt to the stressor, through testosterone induced increases in muscle hypertrophy. A high intake of animal protein producing a positive nitrogen balance is also a proven way to increase muscle mass through increases in testosterone, and the fat content of the meat is partly responsible for this effect.
Dr Robert Barrington’s Nutritional Recommendation: Lifting heavy weights and eating a high animal protein diet are proven ways to build muscle through increases in testosterone levels. Avoiding stress is also important as this is one of the primary ways in which testosterone levels can be diminished. In this regard it is important not to overtrain, as physical activity is a stressor and too much can induce a chronic stress reaction. Adequate rest and sleep is therefore pivotal if this strategy is to work.
RdB

Saturday 18 October 2014

Rosemary

The herb rosemary (Rosmarinus officinalis) is actually a member of the mint family, despite its outwardly different appearance. In fact rosemary’s leaves resemble pine leaves more that the lush green leaves of some of the other members of the mint family such as spearmint or water mint. Rosemary is originally from the mediterranean area, where it was a common herb used for culinary purposes in both Ancient Rome and Ancient Greece. In traditional medicine, rosemary is used to strengthen the mind, and this may relate to the presence of its essential oils. In this regard, rosemary is similar to other members of the mint family that are also a rich source of essential oils. However, the composition of the essential oils differ between the members of the mint family and rosemary has some unique oils not found in other plants.
Within the oils in rosemary are powerful antioxidants, which may confer protection from disease. These antioxidants may be a contributory factor in the aforementioned ability to strengthen the mind because antioxidants can prevent lipid peroxidation in the neurones of the brain. Such lipid peroxidation of neurones in the brain is now thought to be a causative factor in degenerative diseases of the brain. Rosemary can also increase blood flow to the head, perhaps because the antioxidants are able to prevent the oxidation that is now thought to cause impaired blood flow due to free radical induced reductions in nitric oxide. One of the antioxidants in rosemary is rosmarinic acid, and studies suggest that rosmarinic acid is able to decrease levels of inflammation which may relate to its antioxidant properties. Rosemary also appears able to stimulate immune function and in this regard may be a useful herb to prevent infection.
RdB

Friday 10 October 2014

Should We Eat Raw Vegetables?

A high intake of vegetables is associated with improve health outcomes. The exact reason for this is not known, but may relate to the presence of biologically active phytochemicals in plant tissues. Many of these chemicals are secondary metabolites of plants that are absorbed in humans and interact with out biochemistry to cause physiological changes. The flavonoids are such a group of chemicals, but others include the terpenes and the carotenoids. Some nutritionist advocate eating vegetables raw as this prevents the heat of cooking damaging the phytochemicals within the plant tissues. However, evidence shown that some plant chemicals such as lycopene in tomatoes and lutein in spinach are best absorbed following cooking. This likely relates to the fact that heat breaks down the cells walls of the plants and exposes the phytonutrients to our digestive processes. Cooking onions may also increase the bioavailability of the quercetin they contain.
However, it is important to not overcook vegetables, as this may detrimentally affect the nutrient content. A good example of this is broccoli and other cruciferous vegetables. Broccoli contains chemicals called glucosinolates. Broccoli consumption is associated with a reduced risk of cancer because the chemicals it contains can improve detoxification of carcinogens. However, the glucosinolates do not have this effect in their natural state, they much first be converted to isothiocyanates through the action of an enzyme called myrosinase in the plant tissue. This reaction can only happen if the cell wall and internal organelles of the cells are broken open to bring the glucosinolates into contact with the myrosinase enzyme. The heat of cooking is effective at performing this task, but cooking for too long destroys the enzyme and lowers the production of the cancer preventive isothiocyanates.
RdB

Tuesday 7 October 2014

Are There More To Linseeds That Omega 3 Fats?

Flax Seeds (linseeds) contain high amounts of the essential fatty acid alpha linolenic acid (ALA, C18:3 (n-3)). This fatty acid is the parent compound for production of the series 3 eicosanoids, a group of short lived hormones that regulate important cellular functions including inflammation. Flax seeds are unusual because they are one of the few foods that contains more omega-3 fatty acids than omega 6-fatty acids, and this makes them useful in rebalancing the omega-3 to omega-6 fatty acid ratio. The Western diet for example contains too many omega-6 fatty acids and far too few omega-3 fatty acids and this creates an unbalanced eicosanoid production, which is a primary driver of inflammation and disease. Recommendations to eat flax seeds are therefore often based on their unique fatty acid profile.
However, there is more to flax seeds than the fatty acid profile they contain. Flax seeds are an excellent source of dietary fibre and this may account for some of their health benefits. In addition, the fibre component of flax seeds is associated with a group of polyphenolic compounds called the lignans. These lignans are thought to have particular health effects in humans which may relate to their phyto-oestrogen activity. This ability to interact with the oestrogen receptor may explain the anti-cancer effects of flax seed consumption. This is because flax seed consumption has been shown to reduce oestrogen levels in women and may be able to cause a shrinkage of breast cancer tumours. Of course the tough outer seed coat of flax seeds is indigestible to humans and so milling the seeds is necessary in order to release their nutrients for digestion.
RdB

Friday 3 October 2014

L-Tryptophan and 5-Hydroxytryptophan

L-tryptophan is an essential amino acid. That means without a dietary source, humans die. Amazing then that its sale as a supplement was banned in the United Kingdom and the United States. It is present in most foods in the diet, yet its not allowed to be sold isolated in supplements. The reason for this was that a single batch of L-tryptophan caused a number of deaths because it was contaminated during manufacture. This is unfortunate because L-tryptophan is a very useful supplements to induce relaxation and sleep. This relates to the conversion of L-tryptophan to 5-hydroxytryptophan in the brain, a reaction catalysed by the enzyme tryptophan hydroxylase. Subsequently 5-hydroxytryptophan is decarboxylated to serotonin, a reaction characterised by L-aromatic acid decarboxylase. However, there is another way to get the benefits of L-tryptophan. Supplements of a 5-hydroxytryptophan are available, produced from the Griffonia simplicifolia seed. Once ingested 5-hydroxytryptophan enters the brain where it is converted to serotonin, thus having the same ultimate effect as L-tryptophan. Doses of around 50 to 100 mg are able to induce relaxation by increasing serotonin levels and induce sleep by the subsequent conversion of serotonin to melatonin.
RdB

Sunday 28 September 2014

Brazil Nuts

Brazil nuts come from a giant evergreen tree with latin name Bertholletia excelsa. The brazil nut tree grows wild in the Amazon forest, and efforts to cultivate it outside of this area have largely been unsuccessful. This is because the brazil nut tree has an unusual reproductive cycle. Brazil nuts are a great source of selenium, and this related largely to the fact that the soils it grows in are rich in selenium. One brazil nut can provide around the recommended intake for selenium, and four or so nuts can therefore provide somewhere close to optimal levels for most individuals. Those nuts grown in the Manaus-Belem region are higher in selenium than those grown in the Acre-Rondonia region. The mineral rich soils on which the brazil nut trees grow also provide high levels of other minerals, notably chromium. Brazil nuts also contain high amounts of polyunsaturated fatty acids, unlike the monounsaturated fatty acids in most other nuts. However, this makes them particularly prone to rancidity.
RdB

Saturday 20 September 2014

A Rainbow of Colours

The vivid colours in fruits and vegetables are due to the presence of a myriad of plant derived chemicals (phytonutrients) that protect the plant tissues from pests and environmental damage. Many of these chemicals are biologically active in humans, meaning that they are absorbed and enter the blood, and then interact with our cells, causing changes to occur. Some of the most important groups of these chemicals include the flavonoids, the carotenoids, the stilbenes and the terpenes. Many chemicals from these groups are found in edible plants consumed by humans and have been shown to be beneficial to the health when part of the diet.
However, the effects of these chemicals shows variation, and different groups and classes within groups show different but overlapping health benefits. Because the different colours of fruits and vegetables results primarily from them containing different combinations of these chemicals, it makes sense to eat a wide variety of different coloured fruits and vegetables to make sure that a wide range of these chemicals is present in the blood at any one time. The chemicals may also possess synergistic activity, and so the more variation that is present in the diet, the stronger the health benefits may be. Each day a rainbow of colours should therefore be consumed from the wide selection of fruits and vegetables available to us.
RdB