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Oh, Sweet Poison, Thy Name Is Sugar!

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Myself 

By T. V. Antony Raj
.

“It seems like every time I study an illness and trace a path to the first cause, I find my way back to sugar.” – Richard Johnson, Nephrologist, University of Colorado Denver

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What does the word “sugar” mean to you?

To me, anything that tastes sweet: cane sugar (sucrose), beet sugar, brown sugar, corn syrup, glucose, fructose, corn syrup, honey, syrups, sugary drinks, molasses, agave the popular ingredient for tequila, chocolates, toffees, confectioneries, etc.

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Baby and cake icing (Source: tammydeyoungdesigns.com)
Baby and cake icing (Source: tammydeyoungdesigns.com)

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Most of us had our first singular experience of sweetness when we licked the dab of cake icing or a drop of honey from the finger of one of our loving parents.

Even though sugar tastes delicious it is not a food.

Though it is habit-forming it is not a drug, but many people get addicted to it.

The more sugar you taste, the more you want.

Sugar provides instant energy and quickens the muscles, but it is not a nutrient.

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Old Lady enjoying her huge ice cream (Source: Lupe Clemente/flickr.com)
Old Lady enjoying her huge ice cream (Source: Lupe Clemente/flickr.com)

.

Sugar is the universal name for a variety of carbohydrates, derived from various sources.

Carbohydrates supply energy for working muscles. They provide fuel for the central nervous system, enable fat metabolism, and prevent the protein from being used as energy.

Before learning to grow food, the carbohydrates that our ancestors consumed for energy must have come from whatever plants that were available to them according to the season.

Around 6,000 BC, people in New Guinea cultivated sugarcane. They drank the sweet juice by chewing the stalks of the sugarcane. The cultivation of sugarcane spread gradually from island to island, and around 1000 BC reached the Asian mainland. By 500 BC, the Indians were processing crystalline sugar from sugarcane. By 600 AD sugar found its way to China, Persia, and northern Africa. Eventually, by the 11th century, it reached Europe. In England between the 18th and 19th centuries consumption of sugar increased by 1,500 percent.

By the mid 19th century, Europeans, Americans and the people of the civilized world became habituated to the use of refined sugar and considered it as a staple item of food.

Now, we consume sugar daily in one form or another because our body cells depend on carbohydrates for energy. An ingrained love for sweetness has evolved within us and we use sugar generously to sweeten almost all our raw, cooked, baked, frozen food and drinks.

There is good and bad food. Health experts point their finger accusingly at all foods that have sugar and brand them bad. They say that we are in fact poisoning ourselves by satiating our sweet tooth. Some even use the adjective ‘toxic’ to describe sugar and say it disrupts the body’s usual hormonal cycles and endangers our internal and external organs.

All experts say the use of sugar results in high rates of obesity, metabolic disorders like diabetes, high blood pressure, heart disease, and many other ailments.

Testing urine by smelling and tasting was once the primary method used to diagnose diseases. Hippocrates (460-377 BC) of Kos noticed that a patient’s urine smelled differently as the course of fever changed. The Greco-Roman doctor Galen (131-201 AD) of Pergamon believed that urine revealed the health of the liver, where blood was supposedly produced. He stated, evaluating the urine was the best way to find whether or not the body’s four humours – blood, phlegm, yellow and black bile – were in equilibrium.

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Thomas Willis (1621–1675) by John Wollaston (Bodleian Libraries, University of Oxford)
Thomas Willis (1621–1675) by John Wollaston (Bodleian Libraries, University of Oxford)

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In 1675, Thomas Willis (1621-1675), an English physician who played an important part in the history of anatomy, neurology and psychiatry, and a founding member of the Royal Society of London, was the first in modern medical literature to diagnose diabetes by the taste of urine. He observed that the urine of the diabetics tasted “wonderfully sweet, as if it were imbued with honey or sugar.” His taste test impelled him to append the latin word ‘mellitus‘ for honey to this form of diabetes. Ancient  Hindu, Chinese, and Arab texts also have reports of the same sweet taste in urine of patients suffering from diabetes.

Haven Emerson (1874-1957), Emeritus Professor of Public Health Practice at Columbia University, New York, pointed out that significant increase in deaths from diabetes between 1900 and 1920 corresponded with an increase in sugar consumption.

In the 1960s a series of experiments on animals and humans conducted by John Yudkin, the British nutrition expert revealed that high amounts of sugar in the diet led to high levels of fat that paved the way for heart disease and diabetes. But Yudkin’s warning was not heard because other scientists blamed the rising rates of obesity and heart disease to cholesterol caused by much-saturated fat in the diet.

Even though the Americans changed their diet by consuming less fat than they did 20 years before, obesity increased.

Why?

The culprit was sugar and fructose in particular.

Now, we eat most of our sugar mainly as sucrose or table sugar. Americans include high-fructose corn syrup as well.

One molecule each of two simple sugars – glucose and fructose, having the same chemical formula, but with slightly different molecular structures, bond together to form a molecule of sucrose.

Because fructose is about twice as sweet as glucose, an inexpensive syrup mixing the two was an appealing alternative to sucrose from sugarcane and beets. In the 1960s, the U.S. corn industry developed a new technology to convert corn-derived glucose into fructose from which high fructose corn syrup was produced. Despite its name, the high fructose corn syrup has 55% fructose, 42% glucose, and three percent other sugars.

The various avatars of sugar are metabolized differently in the body. Our body cells prefer the simple sugars fructose and glucose to the heavier disaccharide sucrose. Enzymes such as sucrase in the intestine split sucrose into fructose and glucose instantaneously. Glucose travels through the bloodstream to all of our tissues.

The human body regulates the amount of glucose in the blood. Glucose reaches all the tissues in the body through the bloodstream. It stimulates the pancreas to secrete insulin, the hormone which helps remove excess glucose from the blood, and boosts production of leptin, the hormone which suppresses hunger.

All body cells convert glucose into energy, but only liver cells can convert fructose to energy by metabolizing it into glucose and lactate.

Too much fructose from sugars and sugary drinks including fruit juices taxes the liver by making it spend much energy on converting and leaving less for all its other functions. This leads to excess production of uric acid that induces the formation of gout, kidney stones and leads to high blood pressure. According to some researchers, large amounts of fructose encourage people to eat more than they need since it raises the levels of ghrelin, the hormone that stimulates hunger.

Sugar also triggers the body to increase production of Low-density lipoprotein (LDL) cholesterol often informally called bad cholesterol. LDL cholesterol transports their content of many fat molecules into artery walls, attract macrophages, and thus drive atherosclerosis.

Also, excess fructose increases fat production, especially in the liver. The fat converts to circulating triglycerides that are easily stored in fatty tissue, leading to obesity and a risk factor for clogged arteries and cardiovascular diseases.

Some researchers have linked a fatty liver to insulin resistance – a condition in which cells become unusually less responsive to insulin, exhausting the pancreas until it loses the ability to regulate blood glucose levels properly.

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Richard J. Johnson, MD, University of Colorado
Richard J. Johnson, MD, University of Colorado Denver

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Richard J. Johnson, a nephrologist at the University of Colorado Denver has proposed that uric acid produced by fructose metabolism also promotes insulin resistance thought to be a major contributor to obesity and Type 2 diabetes, the disorders that often occur together.

Rich Cohen in his article “Sugar Love” (A not so sweet story) published in the National Geographic quotes Dr Richard J. Johnson:

“It seems like every time I study an illness and trace a path to the first cause, I find my way back to sugar.

Why is it that one-third of adults [worldwide] have high blood pressure when in 1900 only 5 percent had high blood pressure? Why did 153 million people have diabetes in 1980, and now we’re up to 347 million? Why are more and more Americans obese? Sugar, we believe, is one of the culprits, if not the major culprit.”

Now, more than one-third of adults and nearly 12.5 million adolescents and children are obese in the United States. In 1980 about 5.6  million Americans were diagnosed with diabetes. However, in 2011 more than 20 million Americans were found to be diabetic.

Dr Arun Bal, diabetic foot surgeon warns:

“India is facing an epidemic of diabetes. At present, confirmed diabetes patients in India are 67 million, with another 30 million in prediabetes group. By 2030, India will have the largest number of [diabetic] patients in the world. Diabetes is not only a blood sugar problem but brings along other complications as well.”

Dr Suresh Vijan, an Interventional cardiologist, also warns:

“The incidence of heart disease is increasing at a rapid rate. It was 1.09% in the 1950s, increased to 9.7 % in 1990, and 11% by 2000. This rising trend will make India the heart disease capital of the world… Indians face a dual risk of heart disease and diabetes. The risk of death due to myocardial infarction is three times higher in diabetics as compared with non-diabetics. Life expectancy too is reduced by 30% in diabetics as compared to non-diabetics; this translates into a loss of eight years of life… Increased consumption of dense-rich foods along with increasing sedentary lifestyle has increased the incidence of diabetes and heart disease.”

Robert Lustig of the University of California, San Francisco, is crusading against the use of sugar. His YouTube videos “Sugar: The Bitter Truth,” and “Fat Chance: Fructose 2.0” have gone viral.

It’s not just the heart, diabetes takes a severe toll on vision too.

.

Don't Lick the spoon !(Source: news.discovery.com)
Don’t Lick the spoon ! (Source: news.discovery.com)

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The Different Avatars of Sugar

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.
Myself 

By T. V. Antony Raj
.

Image source: nourition.com
Image source: nourition.com

.

Sugar is the universal name for a variety of carbohydrates or saccharides that have a sweet taste.

The word ‘sugar’ immediately brings to our mind the white crystals we add to tea and coffee to make it sweet.

However, scientifically, the term ‘sugar’ refers to various types of substances derived from different sources: simple sugars known as monosaccharides, and compound sugars: disaccharides, oligosaccharides and polysaccharides.

Any word that ends with “-ose” would most probably denote a sugar.

The range of sweetness we experience when eating foods is determined by the different proportions of sugars found in them.

Many chemically-different substances that are non-carbohydrates may also have a sweet taste but are not classified as sugars. Some of these are used as low-calorie food substitutes for sugar and are categorized as artificial sweeteners.

Saccharides

Saccharides (Greek sacchar: sugar)  are one of the most important biomolecules. They are also known as carbohydrates and control the energy in cells, provide structural integrity, and provide a role in the immune system, development and fertilization in all living things.

Natural saccharides are generally simple carbohydrates called monosaccharides having the general formula (CH2O)n  where n is three or more.

Plants use carbohydrates to store energy and to provide supporting structures. Animals and humans consume plants to get their share of carbohydrates as a source of carbon atoms for the synthesis of other compounds.

Carbohydrates supply energy for working muscles. They provide the fuel for the central nervous system, enable fat metabolism, and prevent protein from being used as energy.

Monosaccharides

Monosaccharides (Greek monos: single, sacchar: sugar) or simple sugars are the most basic units of carbohydrates with the general formula C6H12O6. Examples of Monosaccharides include Glucose (dextrose), fructose (levulose) and galactose. They have one sugar unit with six carbon atoms and five hydroxyl groups (−OH).  They are the building blocks of disaccharides and polysaccharides (such as cellulose and starch). 

Monosaccharides normally found in food (Source: socialphy.com)
Source: socialphy.com

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Each carbon atom that supports a hydroxyl group (except for the first and last) is chiral (a molecule that has a non-superposable mirror image), giving rise to a number of isomeric dextro– and laevo-rotatory forms all with the same chemical formula. For instance, galactose and glucose are both aldohexoses but have different physical structures and chemical properties.

Monosaccharides form an aqueous solution when dissolved in water.

Glucose

Glucose, also known as D-glucose, dextrose, corn sugar, grape sugar and blood sugar is a simple dietary monosaccharide found in plants. It is one of the three dietary monosaccharides, along with fructose and galactose, absorbed directly into the bloodstream during digestion.

Glucose

The name “glucose” is derived from the Greek word γλευχος,  meaning “sweet wine, must”. The suffix “-ose” denotes a sugar.

In a biological sense, glucose is found everywhere. It occurs naturally in fruits and plant juices. It is the primary product of photosynthesis. Most ingested carbohydrates get converted into glucose during digestion and it is the form of sugar transported around the bodies of animals in the bloodstream. It is used as an energy source by most organisms, from bacteria to humans.

Use of glucose maybe by either aerobic respiration, anaerobic respiration, or fermentation. Glucose is the human body’s key source of energy, through aerobic respiration, providing about 3.75 kilocalories (16 kilojoules) of food energy per gram. Aerobic respiration requires oxygen.

Simplified reaction:

C6H12O6 (s) + 6 O2 (g) → 6 CO2 (g) + 6 H2O (l) + heat
ΔG = −2880 kJ per mol of C6H12O6

The negative ΔG indicates that the reaction can occur spontaneously.

Glucose can be manufactured from starch by the addition of enzymes or in the presence of acids. Glucose syrup is a liquid form of glucose that is widely used in the manufacture of foodstuffs.

Fructose

Fructose or fruit sugar, is a simple dietary monosaccharide found in honey, fruits that grow on trees and vines, flowers, berries, and most root vegetables. It is the sweetest of the sugars.

Fructose

Fructose, a 6-carbon polyhydroxy ketone is an isomer of glucose – both have the same molecular formula (C6H12O6) but they differ structurally. It is often bonded to glucose to form the disaccharide sucrose.

Along with glucose and galactose, fructose is absorbed directly into the bloodstream during digestion.

Commercially, fructose is processed from sugarcane, sugar beets, and maize.

Galactose

Galactose (Greek galakt: milk), a monosaccharide sugar, is a constituent of the disaccharide lactose along with the glucose. It does not occur in the free state. It is less sweet than glucose.

Galactose

Galactose is a component of the antigens found on the surface of red blood cells that determine blood groups.

Disaccharides

Sucrose, maltose, and lactose are compound sugars or disaccharides, with the general formula  C12H22O11. They are formed by the combination of two monosaccharide molecules with the exclusion of a molecule of water.

Sucrose

Sucrose is the granulated sugar that we customarily use as additive in our food. It is a disaccharide with one molecule of glucose covalently linked to one molecule of fructose.

Sucrose

Animated sucrose molecule model
Model of a sucrose molecule (Author: RedAndr)

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Sucrose is found in the stems of sugar cane and roots of sugar beet. It also occurs naturally alongside fructose and glucose in other plants, in particular fruits and some roots such as carrots.

After eating, during digestion, a number of enzymes known as sucrase split sucrose into its constituent parts, glucose and fructose.

Maltose

Maltose, also known as maltobiose or malt sugar, is a disaccharide formed during the germination of certain grains, the most notable one being barley, which is converted into malt, the source of the sugar’s name. It is less sweet than sucrose, glucose, or fructose.

Maltose

A molecule of maltose is formed by the combination of two molecules of glucose.

Maltose is formed in the body during the digestion of starch by the enzyme amylase and is itself broken down during digestion by the enzyme maltase.

Lactose

Lactose is the naturally occurring disaccharide derived from galactose and glucose found in milk. A molecule of lactose.is formed by the combination of a molecule of galactose with a molecule of glucose.

Lactose

A molecule of galactose is formed by the combination of a molecule of glucose with a molecule of lactose.

After consuming milk, during digestion, lactose  is broken down into its constituent parts by the enzyme lactase. Children have this enzyme in them. In some adults, the enzyme lactase does not form as they grow up and are unable to digest lactose.

Oligosaccharides

Oligosaccharides (Greek oligos: a few, sacchar: sugar) are polymeric carbohydrate molecules containing a small number, typically three to nine, monosaccharide units. They are commonly found on the plasma membrane of animal cells where they play a role in cell recognition.

Fructo-oligosaccharides (FOS)

Fructo-oligosaccharides, also sometimes called oligofructose or oligofructan, are oligosaccharide fructans. They consist of short chains of fructose molecules.

FOS occur naturally and are found in many vegetables.

FOS exhibit sweetness levels between 30 and 50 percent of sugar in commercially prepared syrups and are used as an alternative sweetener. Due to consumer demand for healthier and calorie-reduced foods, FOS emerged commercially in the 1980s.

The range of sweetness we experience when eating foods is determined by the different proportions of sugars found in them.

Galactooligosaccharides (GOS)

Galactooligosaccharides  occur naturally and consist of short chains of galactose molecules. These compounds can be only partially digested by humans.

Mannan oligosaccharides (MOS)

Mannan oligosaccharides (MOS) are widely used in animal feed to improve gastrointestinal health, energy levels and performance. They are normally obtained from the yeast cell walls of Saccharomyces cerevisiae.

Polysaccharides

Polysaccharides are polymeric carbohydrate molecules composed of long chains of monosaccharide units bound together by glycosidic bonds. Typically, polysaccharides contain more than ten monosaccharide units. Cellulose, starch, glycogen, xanthan gum in plants, etc., are polysaccharides.

3D structure of cellulose, a beta-glucan polysaccharide. (Autho - Ben Mills)
3D structure of cellulose, a beta-glucan polysaccharide. (Autho – Ben Mills)

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Polysaccharides have a general formula of Cx(H2O)y where x is usually a large number between 200 and 2500. Considering that the repeating units in the polymer backbone are often six-carbon monosaccharides, and the general formula can also be represented as (C6H10O5)n where 40≤n≤3000.

Definitions of how large a carbohydrate must be to fall into the categories polysaccharides or oligosaccharides vary according to personal opinions of scientists.

Polysaccharides are an important class of biological polymers. Their function in living organisms is usually either structure or storage-related. Starch (a polymer of glucose) is used as a storage polysaccharide in plants, being found in the form of both amylose and the branched amylopectin. In animals, the structurally similar glucose polymer is the more densely branched glycogen, sometimes called ‘animal starch’. Glycogen’s properties allow it to be metabolized more quickly, which suits the active lives of moving animals.

The different proportions of sugars found in food determine the range of sweetness we experience when eating them.

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Sugar – Part 3: Oh Sweet Poison, Thy Name is Sugar!

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Myself . By T.V. Antony Raj
.

“It seems like every time I study an illness and trace a path to the first cause, I find my way back to sugar.”
– Richard Johnson, Nephrologist, University of Colorado Denver

.

What does the word “sugar” mean to you?

To me, anything that tastes sweet: cane sugar (sucrose), beet sugar, brown sugar, corn syrup, glucose, fructose, corn syrup, honey, syrups, sugary drinks, molasses, agave the popular ingredient for tequila, chocolates, toffees, confectioneries, etc.

Baby and cake icing (Source: tammydeyoungdesigns.com)
Baby and cake icing (Source: tammydeyoungdesigns.com)

Most of us had our first singular experience of sweetness when we licked the dab of cake icing or a drop of honey from the finger of one of our loving parents.

Even though sugar tastes delicious it is not a food. Though it is habit-forming it is not a drug, but many people get addicted to it. The more sugar you taste, the more you want! It gives instant energy and quickens the muscles, but it is not a nutrient.

Old Lady enjoying her huge ice cream (Source: Lupe Clemente/flickr.com)
Old Lady enjoying her huge ice cream (Source: Lupe Clemente/flickr.com)

Sugar is the universal name for a variety of carbohydrates, derived from various sources.

Carbohydrates supply energy for working muscles. They provide fuel for the central nervous system, enable fat metabolism, and prevent protein from being used as energy.

Before learning to grow food, the carbohydrates that our ancestors consumed for energy must have come from whatever plants that were available to them according to the season.

Around 6,000 BC, people in New Guinea cultivated sugarcane. They drank the sweet juice by chewing the stalks of the sugarcane. The cultivation of sugarcane spread gradually from island to island, and around 1000 BC reached the Asian mainland. By 500 BC, the Indians were processing crystalline sugar from sugarcane. By 600 AD sugar found its way to China, Persia, and northern Africa. Eventually by the 11th century, it reached Europe. In England between the 18th and 19th centuries consumption of sugar increased by 1,500 percent.

By the mid 19th century, Europeans, Americans and the people of the civilized world became habituated to the use of refined sugar and considered it as a staple item of food.

Now, we consume sugar daily in one form or another because our body cells depend on carbohydrates for energy. An ingrained love for sweetness has evolved within us and we use sugar generously to sweeten almost all our raw, cooked, baked, frozen food and drinks.

There is good and bad food. Health experts point their finger accusingly at all foods that have sugar and brand them bad. They say that we are in fact poisoning ourselves by satiating our sweet tooth. Some even use the adjective ‘toxic’ to describe sugar and say it disrupts the body’s usual hormonal cycles and endangers our internal and external organs.

All experts say the use of sugar results in high rates of obesity, metabolic disorders like diabetes, high blood pressure, heart disease, and many other ailments.

Testing urine by smelling and tasting was once the primary method used to diagnose diseases. Hippocrates (460-377 BC) of Kos noticed that a patient’s urine smelled differently as the course of fever changed. The Greco-Roman doctor Galen (131-201 AD) of Pergamon believed that urine revealed the health of the liver, where blood was supposedly produced. He stated, evaluating the urine was the best way to find whether or not the body’s four humours – blood, phlegm, yellow and black bile – were in equilibrium.

Thomas Willis (1621–1675) by John Wollaston (Bodleian Libraries, University of Oxford)
Thomas Willis (1621–1675) by John Wollaston (Bodleian Libraries, University of Oxford)

In 1675, Thomas Willis (1621-1675), an English physician who played an important part in the history of anatomy, neurology and psychiatry, and a founding member of the Royal Society of London, was the first in modern medical literature to diagnose diabetes by the taste of urine. He observed that the urine of the diabetics tasted “wonderfully sweet, as if it were imbued with honey or sugar.” His taste test impelled him to append the latin word ‘mellitus‘ for honey to this form of diabetes. Ancient  Hindu, Chinese, and Arab texts also have reports of the same sweet taste in urine of patients suffering from diabetes.

Haven Emerson (1874-1957), Emeritus Professor of Public Health Practice at Columbia University, New York, pointed out that significant increase in deaths from diabetes between 1900 and 1920 corresponded with an increase in sugar consumption.

In the 1960s a series of experiments on animals and humans conducted by John Yudkin, the British nutrition expert revealed that high amounts of sugar in the diet led to high levels of fat that paved the way for heart disease and diabetes. But Yudkin’s warning was not heard because other scientists blamed the rising rates of obesity and heart disease to cholesterol caused by too much saturated fat in the diet.

Even though the Americans changed their diet by consuming less fat than they did 20 years before, obesity increased.

Why?

The culprit was sugar and fructose in particular.

Now, we eat most of our sugar mainly as sucrose or table sugar. Americans include high-fructose corn syrup as well.

One molecule each of two simple sugars – glucose and fructose, having the same chemical formula, but with slightly different molecular structures, bond together to form a molecule of sucrose.

Because fructose is about twice as sweet as glucose, an inexpensive syrup mixing the two was an appealing alternative to sucrose from sugarcane and beets. In the 1960s, the U.S. corn industry developed a new technology to convert corn-derived glucose into fructose from which high fructose corn syrup was produced. Despite its name, the high fructose corn syrup has 55% fructose, 42% glucose, and three percent other sugars.

The various avatars of sugar are metabolized differently in the body. Our body cells prefer the simple sugars fructose and glucose to the heavier disaccharide sucrose. Enzymes such as sucrase in the intestine split sucrose into fructose and glucose instantaneously. Glucose travels through the bloodstream to all of our tissues.

The human body regulates the amount of glucose in the blood. Glucose reaches all the tissues in the body through the bloodstream. It stimulates the pancreas to secrete insulin, the hormone which helps remove excess glucose from  the blood, and boosts production of leptin, the hormone which suppresses hunger.

All body cells convert glucose into energy, but only liver cells can convert fructose to energy by metabolizing it into glucose and lactate.

Too much fructose from sugars and sugary drinks including fruit juices, taxes the liver by making it spend much energy on converting and leaving less for all its other functions. This leads to excess production of uric acid that induces formation of gout, kidney stones and leads to high blood pressure. According to some researchers large amounts of fructose encourage people to eat more than they need since it raises the levels of grehlin, the hormone that stimulates hunger.

Sugar also triggers the body to increase production of Low-density lipoprotein (LDL) cholesterol often informally called bad cholesterol. LDL cholesterol transports their content of many fat molecules into artery walls, attract macrophages, and thus drive atherosclerosis.

Also, excess fructose increases fat production, especially in the liver. The fat converts to circulating triglycerides that are easily stored in fatty tissue, leading to obesity and a risk factor for clogged arteries and cardiovascular diseases.

Some researchers have linked a fatty liver to insulin resistance – a condition in which cells become unusually less responsive to insulin, exhausting the pancreas until it loses the ability to regulate blood glucose levels properly.

Richard J. Johnson, a nephrologist at the University of Colorado Denver has proposed that uric acid produced by fructose metabolism also promotes insulin resistance thought to be a major contributor to obesity and Type 2 diabetes, the disorders that often occur together.

Richard J. Johnson, MD, University of Colorado
Richard J. Johnson, MD, University of Colorado Denver

Rich Cohen in his article “Sugar Love” (A not so sweet story) published in the National Geographic quotes Dr. Richard J. Johnson:

“It seems like every time I study an illness and trace a path to the first cause, I find my way back to sugar.

Why is it that one-third of adults [worldwide] have high blood pressure, when in 1900 only 5 percent had high blood pressure? Why did 153 million people have diabetes in 1980, and now we’re up to 347 million? Why are more and more Americans obese? Sugar, we believe, is one of the culprits, if not the major culprit.”

Now, more than one-third of adults and nearly 12.5 million adolescents and children are obese in the United States. In 1980 about 5.6  million Americans were diagnosed with diabetes. However, in 2011 more than 20 million Americans were found to be diabetic.

Dr. Arun Bal, diabetic foot surgeon warns:

“India is facing an epidemic of diabetes. At present, confirmed diabetes patients in India are 67 million, with another 30 million in prediabetes group. By 2030, India will have the largest number of [diabetic] patients in the world. Diabetes is not only a blood sugar problem, but brings along other complications as well.”

Dr. Suresh Vijan, Interventional cardiologist, also warns:

“The incidence of heart disease is increasing at a rapid rate. It was 1.09% in the 1950s, increased to 9.7 % in 1990, and 11% by 2000. This rising trend will make India the heart disease capital of the world… Indians face a dual risk of heart disease and diabetes. The risk of death due to myocardial infarction is three times higher in diabetics as compared with non-diabetics. Life expectancy too is reduced by 30% in diabetics as compared to non diabetics; this translates into a loss of eight years of life… Increased consumption of dense-rich foods along with increasing sedentary lifestyle has increased the incidence of diabetes and heart disease.”

Robert Lustig of the University of California, San Francisco, is crusading against the use of sugar. His YouTube videos “Sugar: The Bitter Truth,” and “Fat Chance: Fructose 2.0” have gone viral.

It’s not just the heart, diabetes takes a severe toll on vision too.

.

Don't Lick the spoon !(Source: news.discovery.com)
Don’t Lick the spoon ! (Source: news.discovery.com)

.

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#WPLongform, Food, Nutrition, Post A Day 2014, Sugar, tvaraj

Sugar – Part 2: The Different Avatars of Sugar

5 Comments

.
Myself . By T.V. Antony Raj
.

Image source: nourition.com
Image source: nourition.com

Sugar is the universal name for a variety of carbohydrates or saccharides that have a sweet taste.

The word ‘sugar’ immediately brings to our mind the white crystals we add to tea and coffee to make it sweet.

However, scientifically, the term ‘sugar’ refers to various types of substances derived from different sources: simple sugars known as monosaccharides, and compound sugars: disaccharides, oligosaccharides and polysaccharides.

Any word that ends with “-ose” would most probably denote a sugar.

The range of sweetness we experience when eating foods is determined by the different proportions of sugars found in them.

Many chemically-different substances that are non-carbohydrates may also have a sweet taste, but are not classified as sugars. Some of these are used as low-calorie food substitutes for sugar and are categorized as artificial sweeteners.

Saccharides

Saccharides (Greek sacchar: sugar)  are one of the most important biomolecules. They are also known as carbohydrates and control the energy in cells, provide structural integrity, and provide a role in the immune system, development and fertilization in all living things.

Natural saccharides are generally simple carbohydrates called monosaccharides having the general formula (CH2O)n  where n is three or more.

Plants use carbohydrates to store energy and to provide supporting structures. Animals and humans consume plants to get their share of carbohydrates as a source of carbon atoms for synthesis of other compounds.

Carbohydrates supply energy for working muscles. They provide the fuel for the central nervous system, enable fat metabolism, and prevent protein from being used as energy.

Monosaccharides

Monosaccharides (Greek monos: single, sacchar: sugar) or simple sugars are the most basic units of carbohydrates with the general formula C6H12O6 . Examples of Monosaccharides include Glucose (dextrose), fructose (levulose) and galactose. They have one sugar unit with six carbon atoms and five hydroxyl groups (−OH).  They are the building blocks of disaccharides and polysaccharides (such as cellulose and starch). 

Monosaccharides normally found in food (Source: socialphy.com)
Source: socialphy.com

Each carbon atom that supports a hydroxyl group (except for the first and last) is chiral (a molecule that has a non-superposable mirror image), giving rise to a number of isomeric dextro– and laevo-rotatory forms all with the same chemical formula. For instance, galactose and glucose are both aldohexoses, but have different physical structures and chemical properties.

Monosaccharides form an aqueous solution when dissolved in water.

Glucose also known as D-glucose, dextrose, corn sugar, grape sugar and blood sugar is a simple dietary monosaccharide found in plants. It is one of the three dietary monosaccharides, along with fructose and galactose, that are absorbed directly into the bloodstream during digestion.

Glucose

The name “glucose” is derived from the Greek word γλευχος, meaning “sweet wine, must”. The suffix “-ose” denotes a sugar.

In a biological sense, glucose is found everywhere. It occurs naturally in fruits and plant juices. It is the primary product of photosynthesis. Most ingested carbohydrates are converted into glucose during digestion and it is the form of sugar that is transported around the bodies of animals in the bloodstream. It is used as an energy source by most organisms, from bacteria to humans.

Use of glucose may be by either aerobic respiration, anaerobic respiration, or fermentation. Glucose is the human body’s key source of energy, through aerobic respiration, providing about 3.75 kilo calories (16 kilojoules) of food energy per gram. Aerobic respiration requires oxygen.

Simplified reaction:

C6H12O6 (s) + 6 O2 (g) → 6 CO2 (g) + 6 H2O (l) + heat
ΔG = −2880 kJ per mol of C6H12O6

The negative ΔG indicates that the reaction can occur spontaneously.

Glucose can be manufactured from starch by the addition of enzymes or in the presence of acids. Glucose syrup is a liquid form of glucose that is widely used in the manufacture of foodstuffs.

Fructose or fruit sugar, is a simple dietary monosaccharide found in honey, fruits that grow on trees and vines, flowers, berries, and most root vegetables. It is the sweetest of the sugars.

Fructose

Fructose, a 6-carbon polyhydroxyketone is an isomer of glucose – both have the same molecular formula (C6H12O6) but they differ structurally. It is often bonded to glucose to form the disaccharide sucrose.

Along with glucose and galactose, fructose is absorbed directly into the bloodstream during digestion.

Commercially, fructose is processed from sugarcane, sugar beets, and maize.

Galactose (Greek galakt: milk), a monosaccharide sugar, is a constituent of the disaccharide lactose along with the glucose. It does not occur in the free state. It is less sweet than glucose.

Galactose

Glactose, is a component of the antigens found on the surface of red blood cells that determine blood groups.

Disaccharides

Sucrose, maltose, and lactose are compound sugars or disaccharides, with the general formula  C12H22O11. They are formed by the combination of two monosaccharide molecules with the exclusion of a molecule of water.

Sucrose is the granulated sugar that we customarily use as additive in our food. It is a disaccharide with one molecule of glucose covalently linked to one molecule of fructose.

Sucrose

Animated sucrose molecule model
Model of a sucrose molecule (Author: RedAndr)

Sucrose is found in the stems of sugar cane and roots of sugar beet. It also occurs naturally alongside fructose and glucose in other plants, in particular fruits and some roots such as carrots.

After eating, during digestion, a number of enzymes known as sucrase split sucrose into its constituent parts, glucose and fructose.

Maltose also known as maltobiose or malt sugar, is a disaccharide formed during the germination of certain grains, the most notable one being barley, which is converted into malt, the source of the sugar’s name. It is less sweet than sucrose, glucose, or fructose.

Maltose

A molecule of maltose is formed by the combination of two molecules of glucose.

Maltose is formed in the body during the digestion of starch by the enzyme amylase and is itself broken down during digestion by the enzyme maltase

Lactose is the naturally occurring disaccharide derived from galactose and glucose found in milk. A molecule of lactose.is formed by the combination of a molecule of galactose with a molecule of glucose.

Lactose

A molecule of galactose is formed by the combination of a molecule of glucose with a molecule of lactose.

After consuming milk, during digestion, lactose is broken down into its constituent parts by the enzyme lactase. Children have this enzyme in them. In some adults the enzyme lactase does not form as they grow up and are unable to digest lactose.

Oligosaccharides

Oligosaccharides (Greek oligos: a few, sacchar: sugar) are polymeric carbohydrate molecules containing a small number, typically three to nine, monosaccharide units. They are commonly found on the plasma membrane of animal cells where they play a role in cell–cell recognition.

Fructo-oligosaccharides (FOS), also sometimes called oligofructose or oligofructan, are oligosaccharide fructans. They consist of short chains of fructose molecules.

FOS occur naturally and are found in many vegetables.

FOS exhibit sweetness levels between 30 and 50 percent of sugar in commercially prepared syrups and are used as an alternative sweetener. Due to consumer demand for healthier and calorie-reduced foods, FOS emerged commercially in the 1980s.

The range of sweetness we experience when eating foods is determined by the different proportions of sugars found in them.

Galactooligosaccharides (GOS) occur naturally, and consist of short chains of galactose molecules. These compounds can be only partially digested by humans.

Mannan oligosaccharides (MOS) are widely used in animal feed to improve gastrointestinal health, energy levels and performance. They are normally obtained from the yeast cell walls of Saccharomyces cerevisiae.

Polysaccharides

Polysaccharides are polymeric carbohydrate molecules composed of long chains of monosaccharide units bound together by glycosidic bonds. Typically, polysaccharides contain more than ten monosaccharide units.

Cellulose, starch, glycogen, xanthan gum in plants, etc., are polysaccharides.

3D structure of cellulose, a beta-glucan polysaccharide. (Autho - Ben Mills)
3D structure of cellulose, a beta-glucan polysaccharide. (Autho – Ben Mills)

Polysaccharides, have a general formula of Cx(H2O)y where x is usually a large number between 200 and 2500. Considering that the repeating units in the polymer backbone are often six-carbon monosaccharides, and the general formula can also be represented as (C6H10O5)n where 40≤n≤3000.

Definitions of how large a carbohydrate must be to fall into the categories polysaccharides or oligosaccharides vary according to personal opinions of scientists.

Polysaccharides are an important class of biological polymers. Their function in living organisms is usually either structure or storage-related. Starch (a polymer of glucose) is used as a storage polysaccharide in plants, being found in the form of both amylose and the branched amylopectin. In animals, the structurally similar glucose polymer is the more densely branched glycogen, sometimes called ‘animal starch’. Glycogen’s properties allow it to be metabolized more quickly, which suits the active lives of moving animals.

The range of sweetness we experience when eating foods is determined by the different proportions of sugars found in them.

 

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