Monday, 30 June 2014
Friday, 27 June 2014
Flavonoids and Organic Fruit
Thursday, 26 June 2014
Choline, Betaine and Phosphatidylcholine: Fat Loss Trio
Choline is chemically called tetramethylglycine. When a methyl group is removed from this molecule through normal metabolic activity, it becomes trimethylglycine, also known a betaine. High choline intakes can therefore increase body reserves of betaine. Betaine is also known a lipotropic factor because of its ability to aid in the processing of fats from the liver. In this regard, betaine is helpful in the treatment of alcoholic fatty liver that develops from over consumption of ethanol. Animal and human studies show that betaine supplements can improve the clinical symptoms of fatty liver. Non-alcoholic fatty liver is a closely related disease that is caused not by alcohol, but by fructose. High intakes of fructose in the diet can cause fat accumulation in the liver and this leads to insulin resistance and weight gain. The high fructose contents of foods and drinks such as confectionary and soft drinks is now thought to be a direct cause of obesity.
The fact that betaine is beneficial at treating alcoholic fatty liver suggest that it may also be effective at treating the non-alcoholic fatty liver associated with fructose consumption. Interestingly, a number of vegetables are high in betaine and choline, which may explain some of the weight loss effects of a high plant food diet. Beetroot is a great source of betaine (~150 mg per 100 g). Spinach is an even better source of betaine (~750 mg per 100 g). Legumes and cruciferous vegetables such as broccoli, cauliflower and brussel sprouts are an excellent source of choline. Supplemental lecithin is also an effective way to supply choline as structurally lecithin is phosphatidylcholine, a fatty acid type molecule with a molecule of choline attached. Lecithin is known to have fat oxidising effect in liver tissue and is therefore recommended in any fat loss diet. Eggs are an excellent (eggsellent!!) source of phosphatidylcholine.
Wednesday, 25 June 2014
Is Obesity a Fibre Deficiency?
Plants are made of carbohydrates, which are sugars synthesised into long chains to create both structural parts of the plant as well as food for seed growth. When we eat plants we eat both of these forms of carbohydrate in a ratio that is in balance without dietary needs. The carbohydrates used as structural components in plants are generally not digestible by humans. As a result we refer to this component as dietary fibre, and the edible component is termed starch.
What Is Dietary Fibre?
Dietary fibre is not a single compound but a group of indigestible carbohydrates. Sugars are bonded together in long chains, and the type of sugars and way they are bonded dictates the type of fibre. Fibres that are common in the human diet include cellulose, pectin, hemicellulose and gums. Humans do not possess the enzymes to break these down and so they are considered by many to not be absorbed, however, this is an erroneous belief in most cases.
Why Is Dietary Fibre Important?
Dietary fibre was once believed to be of relatively little important other than to add roughage to food to aid gastric transit. This viewpoint is still true, but more recently the role of fibre has expanded to other areas. Fibre is now known to provide energy to humans via its bacterial fermentation in the colon to short chain fatty acids. In addition, fibre is essential in delaying the absorption of glucose from many forms of carbohydrate and in this regard may prevent obesity.
Refined Carbohydrates And Obesity
Refined carbohydrates are the main form of carbohydrates in the Western diet. During the refining process, the bran and germ are removed from the grains and this leaves just the tasty starch endosperm. The difference between refined and whole grain cereals can be seen in comparison of whole grain and white bread. Removing the bran and germ also removes most of the fibre, and this is problematic because it causes a loss of control of blood sugar.
The Fibre Insulin Link
Fibre slows the absorption of glucose from carbohydrates and this allows a slow and gradual increase in blood sugar. This slow rise in blood sugar prevent the liver becoming overloaded with energy because it is more able to deal with the influx efficiently. Removing the fibre increases the speed of delivery and as a result the liver becomes overloaded with nutrients. This causes the liver to shift metabolism to the production of fats, especially if the meal contains the sugar fructose.
The insulin resistance caused by fructose and rapid influxes of glucose is a likely driver of obesity. This insulin resistance occurs because the fatty acids produced by liver overload are deposited in skeletal muscle and the liver where they interfere with the action of insulin. Fibre is known to prevent the risk of developing insulin resistance, in fact the simple act of eating tinned beans can significantly reduce this problem in diabetic subjects.
Tuesday, 24 June 2014
Soft Drinks and Phosphorus Imbalance
Monday, 23 June 2014
Low Potassium Diets
Sodium is often blamed for being the causative factor in high blood pressure. Some evidence supports this contention, but generally the scientific evidence in support of a high sodium intake causing detrimental blood pressure changes is not consistent. In particular it appears that healthy individuals eating a normal balanced diet do not develop blood pressure changes from high sodium diets unless the intake is excessively high or for prolonged periods
Nutrients Versus Diets
One of the problems faced by nutritionists when attempting to find causative agents for disease is that often the disease takes decades to manifest. This makes it incredibly hard to identify specific causes as often the diets of individuals with that disease contain many foods that could be to blame. However, recently a shift has occurred that has meant that rather than looking at the effects of individual nutrients on health, nutritionists have started looking at the effects of the diet as a whole.
Western Diets are High in Sodium
The shift in focus from individual food to the diet has a whole has resulted in the Western diet coming under scrutiny. Generally the Western diet is consumed by the Western developed nations and is comprised of mainly red meat, processed meat, refined carbohydrates, fat and sugar. In addition the Western diet is also high in sodium. However, while sodium has been blamed for the high incidence of high blood pressure in Western populations, other factors could be to blame.
High Sodium is Low Potassium
The sodium to potassium ratio in most fruits and vegetables is around 1:50. However, in the Western dirt the ration is more like 2:1 in favour of sodium. While high sodium diets may be associated with high blood pressure, it is difficult to apportion blame because diets high in sodium are also diets low in potassium. Numerous studies have presented evidence that indicates that high sodium diets do not cause high blood pressure without a concomitant low potassium intake.
How To Redress The Balance
If you are currently eating Western foods and add table salt to your foods then you almost certainly will have a sodium potassium imbalance. Cutting out the addition of salt to foods is a start, but will do nothing to reduce the risk of developing high blood pressure without addressing the low potassium intake that is likely part of the diet. Fortunately this is easily achieved addition of fruits and vegetables as replacements for the processed and salted foods that typify the diet.
Saturday, 21 June 2014
Some Thoughts on Cooking Fats
Fats are a useful adjunct during cooking because they supply taste and also serve as a method of transferring heat to the food. Cooking with fats and oils in controversial though because they can react differently to heating, and in turn this may impact health. Understanding cooking fats is therefore important in avoiding deleterious health consequences from their misuse, and can provide information on safer alternative that may benefit health.
Types of Fat
Fats can be saturated or unsaturated. Saturated fats are generally animal fats. Unsaturated fats in contrast are generally plant fats. Unsaturated fats are kinked molecules whereas saturated fats are straight chains. This results from a chemical double bond in unsaturated fats that causes their carbon chains to bend. The bend in the chain alters the melting point of the fat, and for this reason unsaturated vegetable fats are generally liquid and room temperature, whereas animal fats are solid.
Oxidation of Fats
Exposing a fat to heat and light can cause it to react with oxygen and go rancid. Rancid fats when consumed cause disease because they interacts with the cells of the body and disrupts normal function. To go rancid a fat must react with oxygen and for this to happen there must be a reaction site on the fat. The double bonds in unsaturated fats offer a reaction site for oxygen and this makes them far more likely to go rancid when compared to saturated fats.
Cooking with Polyunsaturated Fats
Unsaturated fats are divided into monounsaturated and polyunsaturated fats. Monounsaturated fats have one double bond, but polyunsaturated fats have more than one. This makes polyunsaturated fats far more likely to go rancid. Therefore polyunsaturated fatty acids like sunflower, rape, safflower and corn oil are poor choices for cooking. Many of these oils are also already heavily oxidised during processing, and cooking further deteriorates their quality.
Monounsaturated Cooking Fats
Because monounsaturated fats have only one double bond in their chain they are far more stable than polyunsaturated fats when exposed to light and heat. Therefore they are a far better choice for cooking. However, some monounsaturated fats are better choices than others. Macadamia nut oil contains less polyunsaturated fat than olive oil and this makes it superior for cooking because it has much less chance of going rancid.
The King of Cooking Oils
Coconut oil is a saturated oil. It is unusual for a number of reasons. Firstly, plant oils are usually unsaturated and in this respect coconut oil bucks the trend. Secondly, it is different to most saturated animal fat because it contains fats of shorter carbon chain lengths. Coconut oils is actually rich is medium chain saturated fats with chain lengths of between 8 and 12 carbons, whereas most animals fats comprise of saturated fats with long chain lengths of 18 carbons.
Cooking With Coconut Oil
Cooking with coconut oil is therefore advantageous because it provides relatively stable fats. However its high concentrations of medium chain fats are beneficial too because they have weight loss effects. In particular, medium chain fats are absorbed and passed straight to the liver where they are burnt as fuel. In this way they behave more like carbohydrates in supplying a rapid supply of energy, and in this regard are far less likely to be stored as body fat.
Friday, 20 June 2014
Thursday, 19 June 2014
Fire Burn and Cauldron Bubble
Vegetables are an important source of vitamins, minerals, fibre and phytonutrients. However, generally people do not eat enough of them. The Western diet is devoid of meaningful levels of vegetables and this is one reason it is associated with ill health. Convincing people to eat more vegetables can be hard because some vegetables are difficult to prepare and some have strong tastes. Finding easy to prepare healthy vegetables that do not have strong tastes is therefore an important part of increasing vegetable intake in the general population. Nobody wants to eat foods that taste bad and take up too much time. Frozen vegetables can be a way around this problem. Frozen vegetables tend to maintain their phytonutrient levels from when they were fresh and these levels have been shown to stay higher for longer when compared to fresh produce. In addition they generally require no preparation other than adding them to boiling water.
Much is said about the benefits of steaming compared with boiling. Steaming is said to be beneficial because it allows the retention of more of the nutrients within the vegetables, many of which can leach into the water during boiling. This is true however, in the real world the difference in the health of a person eating steamed or boiled vegetables would likely be negligible. Therefore I recommend cooking the vegetables in the way that best suits your needs at the time. As for the question of fresh versus frozen, I really see little difference in the long term health benefits between the two. Even canned legumes retain much of their nutrient content. The real trick with vegetables is to eat a variety of colours, as the colours of vegetables reflects the phytonutrient content of the plants. In this way your vegetable intake will provide a spectrum of phytonutrients that widens the protective effects from disease.
Wednesday, 18 June 2014
Modified Citrus Pectin
Tuesday, 17 June 2014
Thoughts on Fibre
Dietary fibre is the carbohydrate component of plants that cannot be digested by human enzymes. As a result, dietary fibre passes straight through the small intestine undigested and unabsorbed. Fibre was originally thought of as roughage to provide bulk to the food and nothing more. However, more recent research is starting to uncover the importance of fibre in the human diet and showing that fibre is far more complex than once considered.
Soluble Versus Insoluble Fibre
The two main divisions of fibre are soluble and insoluble fibre. This is an important distinction because these fibre types have very different effects in the body. For example, soluble fibre such as gums, mucilages and pectins are able to create a layer inside the gut and slow the absorption of glucose and thus favourably affect blood sugar levels. In contrast insoluble fibre such as cellulose are an important source of food for gut bacteria.
Short-Chain Fatty Acids
The insoluble fibre cellulose is an important source of food for gut bacteria in the colon. In exchange for supplying these bacteria with cellulose, gut bacteria provide their host with short-chain fatty acids. This process is the same fermentation seen in ruminant animals such as sheep and goats. Most people consider fibre to provide no energy, but the short-chain fatty acids such as propionate, butyrate and acetate are absorbed and used by humans as a source of energy.
Evidence suggest that when fibre is removed from its original plant material it loses some or all of its special properties. This is because normally fibre forms the cells walls of plants and this surrounds the starchy or sugar content of the cell. Eating the food in its whole form means that some or all of these cell walls are intact, and this inhibits the digestion rate of the contents, slowing its absorption. Processing the fibre into breakfast cereal for example destroys this property.
Legumes and Nuts
Nuts are a great source of fibre, but are also high in fat and energy. However, the energy in nuts is not fully absorbed due to the cell walls that encase the contents. Some of the cell walls can be broken open with chewing, but some slip through and the contents remain undigested. The parenchymal cells walls that surround nuts are also present in legumes and this process may also occur in beans and peas. This explains the weight loss effects of nuts and legumes.
What Is The Best Source of Fibre?
The truth it, the best source of fibre is a mixture of all fibre types. There are many fibres including hemicellulose, cellulose, pectin, gum, mucilage and lignan. All of these fibres have different roles to play in health, and health is therefore best supported by a mixture of all fibre types. Studies also show that supplemental fibre does not possess the same health effect as fibre in its food form, so try to get all the fibre you need from your diet.
Monday, 16 June 2014
Phytochemical Levels in Plants
Sunday, 15 June 2014
Some Notes on Sweeteners
Artificial sweeteners are popular because it is claimed they limit calorie intake and thus lead to weight loss. This is based mainly on supposition however, as the nutritional literature does not support this contention. In fact studies on artificial sweeteners show they may actually increase food intake and cause body weight gain. Disregarding any possible effects on weight gain, the ubiquitous nature of artificial sweeteners necessitates a basic understanding of their effects.
Aspartame is perhaps the best known sweetener. It is composed of phenylalanine and aspartic acid, two amino acids, joined to a molecule of methanol. Aspartame is roughly 200 times sweeter than sugar and is now added to products in addition to sugar. In the body aspartame is broken down to formaldehyde, and it is for this reason that aspartame is widely believed to be carcinogenic. In addition, aspartame may alter brain chemistry because of the amino acids it contains.
Stevia is a natural sweetener extracted from the Stevia rebaudiana plant. Stevia is roughly 300 times sweeter than sugar. Stevia is widely used as a sweetener in Japan, but is only available as a dietary supplements in many other countries. A number of glycosides are responsible for the sweet taste is stevia and these have now been isolated and given a generally recognised as safe label by the United States Food and Drug Administration.
Xylitol, Mannitol and Sorbitol
These compounds are described as polyols or polyalcohols. Polyols are roughly 60 time sweeter than sugar. Because they are poorly absorbed they can be added to foods to increase sweetness without changing the energy content of the food too much. However, in larger doses they are known laxatives as they changes the osmotic potential in the gut due to their low absorption. In this regard they can be effective at low doses but at high intakes may be problematic.
Like aspartame, concerns over saccharine centre on the possibility that it is a carcinogen. No convincing human studies have demonstrated a carcinogenic effect, and this is not unusual due to the length of time cancer takes to form. However animals studies involving rats do suggest that saccharine might be carcinogenic. Like aspartame, saccharine is also around 300 times as sweet as sugar and is widely used in many different foods.
Acesulfame K, also called acesulfame potassium (K being the elemental symbol for potassium), is roughly 200 times sweeter than sugar, and is not absorbed by the body. As with aspartame and saccharine, The use of acesulfame K in the food industry as an artificial sweetener is widespread. Acesulfame K can produce a bitter aftertaste when ingested in high concentrations and for this reason is often blended with other sweeteners or used with masking agents such as sodium ferulate.
Sucralose is chemically related to sucrose, but it has additional chlorine atoms attached to its structure. Sucralose is roughly 600 times sweeter than sugar and is not broken down by the body and so does not provide any energy. Sucralose is widely used in baked good because it is heat stable and for this reason has been produced in a granulated form to resemble sugar. Sucralose provides no energy to the body, but is often packaged with dextrose or maltodextrin that do.
Tagatose is a naturally occurring sugar found in milk that is slightly less sweet than sugar. Tagatose is absorbed poorly and while it does supply some calories to the body, it may actually beneficially modulate the glycaemic response to some other sugars through competitive absorption in the intestines. While tagatose can inhibit the absorption of other sugars it has minimal effects on plasma glucose or insulin release itself.
Saturday, 14 June 2014
Can you get all the nutrients you require from food?
Ponderings on Whey Protein Digestion
|Whey protein is more rapidly absorbed than casein when the stomach contents are empty.|
Whey protein is one of the main components of milk, the other being casein. Whey protein has become popular as a sports supplement in its powdered form because it has a number of interesting properties. In particular, whey protein is rapidly absorbed in comparison to casein, and for this reason many sports nutritionist advocate whey protein as a source of nitrogen following a workout. This is based on the premise that post-workout protein is able to stimulate protein synthesis through nitrogen delivery to the circulation, and thus may increase skeletal muscle formation. However, the rapid absorption of whey is dependent on the absence of other proteins from the stomach and small intestine. Concomitant consumption of whey with other foods can slow this absorption and negate whey proteins primary advantage over other proteins like casein and egg protein. Considering that whole protein can remain in the stomach for some hours, consuming whey protein even a long time after consumption of meat may inhibit its absorption rate considerably.
During research into whey protein, the authors are careful to compare digestion rates in subjects with empty stomachs so as not to affect the results. Assuming that such results transfer into the real world is a mistake many advocates of whey protein make. Of course often such advocates are also in the business of selling whey protein, and for this reason their judgement is either biased deliberately, or more usually through ignorance. Studies comparing casein and whey protein do show faster rates of absorption for whey protein. Casein is absorbed more slowly and results in lower peak plasma nitrogen levels when compared to whey protein. However, the slow passage of casein through the stomach ensures that its delivery to the plasma is more prolonged. When whey protein nitrogen delivery to the circulation has already diminished, casein continues to provide a source of nitrogen. Of course this is a moot point if any residual food remains in the stomach, in which case whey protein likely behaves in a similar way to casein.
Friday, 13 June 2014
The Glycaemic Index and Disease
The glycaemic index is a measure of the speed at which a carbohydrate food is digested to its component glucose molecules and the rate at which this glucose is subsequently transported into the blood. This measurement is given a rating through comparison with powdered glucose or white bread. Foods with a higher glycaemic index are more rapidly digested and absorbed and therefore cause a sharper more pronounced rise in blood sugar levels.
Blood Sugar and Insulin
Glucose is absorbed to the blood where it circulates before entering cells to supply them with energy. In order for this to happen the hormone insulin is required. Insulin acts as a key that opens transporters in the cell membranes and this facilitates the entry of glucose. The more glucose that is absorbed to the blood, the more insulin that is required for its transport into cells. Foods high on the glycaemic index therefore cause excessive insulin release.
The Glycaemic Index and Insulin resistance
Regular consumption of high glycaemic index carbohydrates is associated with an increased risk of metabolic dysfunction. This is because rapid influx of glucose to the blood increases the uptake of glucose to the liver and this can result in the synthesis of fats. These fats are thought to accumulate in tissues and interfere with the action of insulin in its cell transport role. In this way high glycaemic index carbohydrates cause a disorder called insulin resistance.
The Glycaemic Index and Abdominal Obesity
Regular consumption of high glycaemic index carbohydrates therefore results in insulin resistance. Insulin resistance causes the cells of the liver and skeletal muscles to become unresponsive to the action of insulin. Instead of being shuttled into cells to be burnt as energy during exercise and for metabolic regulation, the glucose gets pushed into fat cells. This causes weight gain in the abdominal area, a disorder termed abdominal obesity.
The Glycaemic Index and Cardiovascular Disease
The metabolic dysfunction associated with insulin resistance and abdominal obesity increases the risk of cardiovascular disease. This is because the accumulation of fat in the abdomen causes the release of inflammatory cytokines and this increases systemic inflammation. This inflammation increases oxidative stress in the arteries of the body and this causes endothelial dysfunction. Endothelial dysfunction disrupts blood flow and raises blood pressure.
The Glycaemic Index and Cancer
High glycaemic index carbohydrates cause the release of excessive amounts of insulin. This is problematic because insulin also causes the release of insulin-like growth factors. These proteins increase the proliferation of cells and evidence suggests that high circulating levels of insulin-like growth factors can increase the proliferation of cancer cells. This explains the increased risk of cancer with regular consumption of high glycaemic index carbohydrates.
Thursday, 12 June 2014
Orange Juice, What is it Good For?
Wednesday, 11 June 2014
Vitamin B6: The Pain Relief Vitamin
The B group of vitamins play an important role in energy production in human metabolism (ever seen the claims on a cereal box?). That is because the B vitamins act as cofactors to enzymes that regulate the metabolic pathways glycolysis and the citric acid cycle. These pathways are the primary energy producing pathways in the body. However, a number of the B vitamins have other roles in the body. One such role is that of vitamin B6 in the relief of pain.
Vitamin B6 is also called pyridoxine. Following digestion it is absorbed and converted to its active metabolite, pyridoxal phosphate. Pyridoxal phosphate is able to interact with a number of enzymes because it is required as a cofactor. Some of these enzymes are thought to be involved in pathways that inhibit and reduce pain. Therefore higher intakes of vitamin B6 may facilitate these pathways and increase the release of pain relieving chemicals.
Gamma aminobutyric acid (GABA) is an amino acid neurotransmitter. It is used as a signal in the brain to inhibit the transmission of information. When pain signals are sent within the brain, GABA in able to quieten the signals by inhibiting the transfer of the stimulatory neurotransmitters. In this way, GABA can modulate pain and reduce its perception in the brain. Vitamin B6 is required in the synthesis of GABA and high intakes may thus having a pain relieving effect.
Like GABA, serotonin is an inhibitory neurotransmitter. This means that it can also inhibit the transfer of pain signals in the brain and favourably modulate the perception of pain. However, chronic pain can deplete the brain of serotonin through this process. Because serotonin is needed to maintain mood, chronic pain can cause depression. Taking vitamin B6 may boost serotonin production, and thus inhibit pain and prevent its associated depression.
Supplements or food?
The recommended amount of vitamin B6 for pain relief is between 50 to 150 mg per day. A number of foods such as whole grains, liver, red meat, eggs and legumes are good sources of vitamin B6. However, it is unlikely that even 50 mg of vitamin B6 could be consumed in a healthy balanced diet. Supplements are therefore recommended. Supplements also hold the advantage that a consistent intake can be taken, something that is not possible to judge from foods.
Tuesday, 10 June 2014
What’s Lurking in Your Lunchbox?
Monday, 9 June 2014
When Protein Turns Bad
High protein diets cause weight loss. The exact reason for this is not known, but may relate to the ability of protein to induce satiety. The weight loss caused by high protein diets carries health benefits, because being overweight increases the risk of developing a number of diseases. However, high protein diets can carry some risks of their own due to the cooking and preparation methods employed in some meat products.
Cooking animals protein results in the meat becoming burnt. Both grilling and frying can cause this browing on the outer surface of the meat. Chemically, when the meat is heated the proteins in the meat become altered and form compounds called heterocyclic amines. Heterocyclic amines formed from heating animal proteins are detrimental to the health because they are known carcinogens and regular consumption may increase the risk of colon cancer.
Hormones and Pesticides
When animals are fed crops containing pesticide residues, they accumulate in the tissues of the animals. When we eat the animals the pesticides are transferred to us. In addition, a number of hormones are fed to animals to increase their growth, and these too are passed on to consumers in the meat. Many of these chemicals may stimulate the growth of existing cancer cells and may also be carcinogenic themselves.
Nitrites and Nitrates
When meat is processed nitrites and nitrates are often added as preservatives. Processed ham, corned beef, spam and meats in convenience foods all have added nitrites and nitrates. When ingested, nitrites and nitrates are converted to nitrosamine compounds, which are known to be carcinogenic. As with heterocyclic amines, nitrosamines can increase the risk of colon cancer. Interestingly, vitamin C and other reducing agents prevents the formation of nitrosamines.
Organic Meat, Lightly Cooked
Many nutritionists and health experts advise avoiding animals products because of the potential to ingest carcinogenic compounds. In isolation this is reasonable advice, but meat is an important source of vitamins and minerals and the amino acids in protein are required for growth. The obvious solution to this is to eat organic grass fed meat which is of higher quality and contains no pesticide or hormone residues, and cook it lightly to it does not become brown through burning.
A number of plant foods are high in protein. The best examples are nuts and legumes, both of which also contain high amounts of dietary fibre. While nuts are also high in fat, legumes are not, and so if large quantities of plant foods are to be used as a source of protein, legumes are a better choice. Because of the way they are prepared and cooked, plant proteins do not carry the same health risks as some proteins of animal origin and can significantly contribute to protein intake.
Sunday, 8 June 2014
Fresh and Powdered Ginger
Saturday, 7 June 2014
Red Wine Versus White Wine
Red and white wines possess obvious compositional differences, the most visible difference being the colour. The colour differences between red and white wines are a reflection of the chemical compositional differences that exist between the wines. These compositional differences are in turn a reflection of the differences in the manufacturing processes between red and white wines, the former including more of the solid parts of the grapes.
The polyphenolic flavonoids and stilbenes in grapes are localised almost exclusively in the skin, stems and seeds. It is the inclusion of polyphenols that determines the colour and chemical composition of the wine, with red wines undergoing maceration of the solid parts of the grape to allow transfer of the polyphenols to the wine. A fermentation step is then required for red wines to ensure transfer of the polyphenols to the wine to produce the red colour.
In contrast to red wines, white wines do not undergo a maceration step and instead is made by simple mechanical pressing of the red or white grapes. The lack of maceration and inclusion of solid material in the fermentation step prevents the transfer of large quantities of the polyphenols to the wine and this limits the final polyphenolic content of the wine. Because of its lower polyphenolic content, white wine is not considered as beneficial to the health as red wine.
Alcohol and Sulphur Dioxide
The concentration of polyphenol compounds in the final red wine is also dependent on other factors. In particular, the alcohol and sulphur dioxide content of the wine can modify the final amount of polyphenols in the wine. Red wine is often bottled into dark glass, and this is to hide the quite high content of solid residue in the wine that would be visible if the wine was in a clear bottle. Because of its lower polyphenol content, white wine can be bottled in clear bottles.
Seeds or Skins
The point at which the grapes are macerated can also affect the final composition of the red wine. Maceration at low temperatures before fermentation can increase the extraction of anthocyanins and proanthocyanidins from the skins. However, post fermentation maceration increases the proanthocyanidin content from the seeds. The final anthocyanins and proanthocyanidins content varies between 20 to 40 % of the original content of the grape, respectively.
During the aging of wine chemical and enzymatic processes change the chemical composition considerably. In particular, anthocyanins from the original grape, and tannins produced from the oxidation of flavonoids, are degraded to other phenolic compounds. This produces and highly complex mixture of chemicals. The exact composition of the final wine therefore depends on the original flavonoid content of the wine as well as the length of the ageing process.
Friday, 6 June 2014
Thursday, 5 June 2014
The Multiple Health Effects of Plant Foods
The nutritional approach to health differs considerably from that of medicine for a number of reasons. The main difference is that nutrition aims to maintain health before it is lost, whereas medicine looks to treat symptoms once disease develops. In this respect, nutrition is akin to carefully topping up your car with oil to ensure that the engine functions as it should, whereas medicine intervenes only once the oil level drops and the oil light comes on the dashboard. At this point medicine removes the bulb from the warning lamp so the light is extinguished.
A less considered difference between nutrition and modern medicine however is the way in which the drug or nutrient affects the physiology of the body. In the case of the medicine, a single drugs is usually given in order to elicit a large modification to a single component in the body. This often causes rapid changes, a process associated with considerable side effects. In contrast nutrition uses whole foods containing many different compounds, that work in very diverse and synergistic ways to improve health slowly and subtly without causing side effects.
Red wine has very important medicinal properties. In particular, red wine can decrease the risk of developing both cancer and cardiovascular disease, and also has anti-obesogenic properties. However, it is not possible to identify a single component within the wine that causes these effects. Red wine is a complex mixture of many chemicals and the exact composition of red wine is not known. Resveratrol has been identified as providing some of the health effects, but other compounds, including ethanol, undoubtedly contribute to the multiple health effects of red wine.
Green tea, like red wine, is a complex mixture of many different phytochemicals. Green tea contains a number of catechin flavonoids as well as L-theanine and methylxanthines such as caffeine. These compounds may work synergistically to provide the known health effects of green tea that include weight loss, protection from cardiovascular disease and anti-cancer effects. For example catechins, caffeine and L-theanine have all been shown to contribute to the weight loss effects of green tea through synergistic interaction.
Extra virgin olive oil is extracted from olives through use of a mechanical press. In essence then the produce of this process is a liquified version of the original contents of the olive minus some of the cellular debris. Some extra virgin olive oils are unfiltered and this retains more of the cellular material than filtered versions. Olives and olive oil have multiple health effects because like red wine and green tea they are complex mixtures of phytochemicals and other substances that can improve health. In particular olive oil contains monounsaturated fatty acid, triterpenoids and phenylethanoids such as oleuropein, ligustroside and oleacein, as well as flavonoids.
Synergism Within Synergism
Consuming red wine, green tea or olive oil can improve the health considerably if eaten in isolation. The synergism of the nutrients contained within the foods acts in multiple ways in the body to produce subtle and side-effect free improvements in health over the long term. However, combining the three foods together produces an effect an order of magnitude greater that consuming the foods in isolation. The power of such synergistic effect is multiplied many fold each time a new healing food is added to the diet, and this explains the lack of disease in people who consume high quality diets regularly.
Wednesday, 4 June 2014
Red Wine and Gut Health
Tuesday, 3 June 2014
The Bland Diet
Western food is the cause of weight gain and obesity. Overtime, the consumption of a Western diet causes the development of Western lifestyle disease such as cardiovascular disease, type 2 diabetes and cancer. The reason that Western foods cause weight gain and disease is because they are addictive and contain metabolic poisons. The addictive nature of the foods ensures that consumers come back for more, and the metabolic poisons they contain gradually poison the individual until they get fat and succumb to one of the Western lifestyle diseases.
Under normal circumstances the hypothalamus can regulate body weight to within a few grams despite large fluctuations in daily food intake. The reason for this is because it has regulatory mechanisms at its disposal to allow changes in the utilisation of energy. If energy intake increases, the hypothalamus can increase the heat produced following eating and exercise and this burns extra calories. In addition, the appetite is down regulated to reduce subsequent food intake and the resting metabolic rate increases to burn more energy.
Western style diets contain metabolic poisons. Such poisons include fructose, trans fatty acids, oxidised fat and certain food additives such as aspartame. Once absorbed these substances interfere with normal metabolic regulation. The reason they act as metabolic poisons is either because they are not normally naturally present in the diet or because they are not normally present in the diet in the quantities ingested. The metabolic dysfunction they cause leads to insulin resistance and changes to the regulation of energy balance.
Insulin Resistance And Energy Balance
The insulin resistance that develops through eating Western diet causes leptin resistance in the hypothalamus. Leptin is a hormone that reports to the hypothalamus about how much fat we have. Leptin allow the hypothalamus to regulate energy balance accordingly. However, if the hypothalamus becomes resistant to the leptin signal, it thinks fat reserves are low, when actually they are very high. This makes the hypothalamus conserve energy and increase appetite, because the hypothalamus perceives a state of starvation.
Restricting calories when leptin resistance is present is very bad news. Because the hypothalamus perceives a starvation state, cutting calories further restricts the utilisation of energy further. As calories are restricted, the hypothalamus lowers the amount of body heat produced from both exercise and food ingestion, and rapidly reduces the resting metabolic rate by decreasing production of the active T3 version of thyroid hormone. In addition, hyperphagia (hunger) is upregulated. The end result is that it becomes inevitable that at some point, you will gain weight.
It has been shown using animal experiments and human studies that consumption of Western style diet causes activation of the reward pathways in the brain. This is exactly the same response as is seen during consumption of certain addictive drugs. The stimulation of these pathways is because they foods contain high concentrations of salt, sugar and fat, all of which are naturally imprinted to activate these pathways. The result is that consumption of diets containing these foods causes physical addiction and ensures overeating of metabolic poisons.
If the Western diet is the cause of obesity then it follows that avoiding Western foods will reverse the process and restore correct body weight. Consuming foods containing low amounts of fat, sugar and salt is beneficial because it prevents activation of the reward pathways of the brain, and food becomes food again, rather than a drug. At the same time, avoiding Western foods eliminates a major source of metabolic toxins and this allows metabolic pathways involved in energy utilisation and balance to function correctly once more.
The Bland Diet
Eating bland foods causes weight loss. Tuna, chicken, rice, legumes, nuts, fish and green leafy vegetables are bland foods. It is virtually impossible to overeat them unless considerable effort is made and discipline is high. Such foods do not stimulate the reward pathways of the brain and are therefore not addictive. They are also absent of the metabolic poisons present in the Western diet. Eating a diet containing such foods causes weight loss because energy metabolism returns to normal and overeating is very unlikely without the presence of leptin resistance.
Monday, 2 June 2014
Weight Loss and Cancer Protection
Sunday, 1 June 2014
Skipping breakfast is pretty common these days. Many people claim they can’t eat in the morning and many more just like to grab a coffee before work. However, scientific evidence shows that skipping breakfast is a bad idea. In particular, it has been shown that skipping breakfast can lead to weight gain and ill health over the long term. But just why is skipping breakfast such a bad idea and why does it cause weight gain?
The Overnight Fast
During the night the brain continues to use glucose as a source of energy. This glucose is derived partly from the food ingested just before bed, but also from the stores of glycogen in the liver. Overnight these stores become consumed and upon waking liver glycogen is usually mostly depleted. Skipping breakfast and leaving the glycogen stored depleted is not a problem in itself, but it does increase the risk of overeating.
Liver Glycogen and Hunger
Eating less by skipping breakfast seems a logical way to cause weight loss, and many people assume they are doing themselves good by using this strategy. However, science shows that those who skip breakfast eat more at other meals, such that by the end of the day they have caught up on the missed energy. And its worse, because not only do they catch up, those that miss breakfast actually eat more food than if they had eaten breakfast.
Low Quality Catchup
So those that skip breakfast actually eat more than those who eat breakfast. The reason for that is that low blood sugar and low glycogen stores are potent stimulators of appetite. The longer that food deprivation occurs, the greater the risk of overeating due to stimulation of the appetite centres in the brain. And when food is eaten, nott only is more consumed, but also the quality of that food diminishes so the risk of eating junk increases.
Eat Like A King
Eating a healthy breakfast therefore is beneficial to body weight as it prevents overeating later in the day and improves the quality of the food eaten. However, a healthy breakfast does not include sugar laden breakfast cereals devoid of fibre and micronutrients. A high quality breakfast containing fruit, whole grain cereals such as oats, as well as tea and milk should be consumed to ensure a slow release of energy throughout the day.
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