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At Hampton Court, one of King Henry VIII’s sixteenth century palaces outside London, tour guides regale visitors with tales of Henry’s obesity and the miseries he suffered during flare-ups of gout – exquisitely painful episodes of arthritis that come from the buildup of uric acid crystals in joints. Gout was known as “the king’s disease,” because it afflicted wealthy people who could afford the meats and sea foods that trigger uric acid crystal formation. The guides also point out the “confectionary,” a corner room near the kitchen wing, and describe the sugar-rotted royal teeth produced by the then scarce sweetener. The guides do not link Henry’s gout to the royal sweets, but perhaps they should. Sugar is composed of equal parts glucose and fructose, and scientists are now beginning to link increased fructose intake not only to obesity and type II diabetes, but also to increased uric acid in the blood – a risk factor for gout.

What is uric acid

Some uric acid in the blood is normal, because every cell in the body makes uric acid out of purines, chemical compounds that come from the regular breakdown of DNA and RNA as cells recycle themselves. Purines also come from many foods, but are particularly concentrated in red meat, organ meats like liver, many fish and shellfish, and yeasty beverages like beer and red wine. Uric acid in the blood is not bad – it serves as a powerful antioxidant. However, in some genetically susceptible people, uric acid levels become too high because they make too much, or because their kidneys don’t excrete enough into the urine.

When uric acid crystallizes

Abnormally high uric acid levels in the blood, a condition called hyperuricemia, can be present for 10-20 years without any symptoms. But just as minerals crystallize out of water in caves and form stalagmites and stalactites, uric acid can crystallize out of fluids in the body, forming microscopic deposits in tissues, especially kidneys, joints, tendon sheaths and skin. The painful part comes with the inflammation that ensues when the body attempts to eliminate the crystals. The classic case of gout, also known as podagra, begins suddenly with exquisitely painful, bright red swelling in the joint space between the foot and the big toe. Symptoms last from days to weeks.

The swelling comes from inflammatory fluid in the joint space. Diagnosis of gout depends on withdrawing some of this fluid through a needle and examining it under a microscope, where the uric acid crystals show up as pointy spicules which bend light waves in an identifiable way. Fluid withdrawal can also relieve some of the pain, but the mainstays of treatment during acute attacks are anti-inflammatory drugs such as Indocin, ice and or heat, and plenty of water. Prevention of attacks depends on efforts to lower uric acid levels, by diet, weight loss and use of medications that block uric acid production or increase its elimination in the urine.

Fructose is a building block for uric acid

For centuries, dietary advice about gout has revolved around foods high in protein. But as numbers of gout cases climbed steadily over the last forty years and average uric acid levels in people without gout also increased, a correlation with increased sugar consumption began to emerge. Scientists are now studying the relationship of sugar intake to uric acid and gout and also attempting to tie uric acid to hypertension, obesity and heart disease.

Sugar consumption was once rare to non-existent. Table sugar, a mixture of the two simple sugars sucrose and fructose, came only from sugar cane, which originally grew only tropical regions. Sugar’s spread around the world followed trade routes, and accelerated markedly after the discovery of the beet as a sugar source in the 18^th C. But the most dramatic rise in sugar consumption followed the invention of high fructose corn syrup (HFCS) in the 1970s. From work done so far, it appears that sugar’s fructose is a bigger culprit than its glucose in aggravating the metabolic syndrome (obesity, high blood pressure, heart disease and diabetes). And the metabolism of fructose actually produces uric acid.

When the glucose/fructose mix of sugar enters the body, glucose is transported directly into cells for use, but fructose requires processing. This requires energy, provided by ATP (adenosine triphosphate), and ATP breakdown produces uric acid. Eating fructose regularly also makes fructose easier to metabolize because it “induces,” or makes the body produce specific enzymes required to break it down. For someone prone to overproducing uric acid, or someone whose kidneys excrete it inefficiently, a diet chronically high in fructose may not only provide the building blocks for uric acid, but also speed its production.

Cutting fructose may help – and will do no harm

Cutting purine-rich foods down in a diet helps many susceptible people remain gout free. There is no data yet on the effectiveness of limiting fructose intake on gout or hyperuricemia, but such a diet can do no harm. Limiting fructose sources to whole fruits would dramatically lower total fructose intake for most people. Fructose is the major sugar in fruits, but it is combined with fiber and vital nutrients and present in much lesser quantities than in sugar-sweetened beverages, soft drinks, baked goods and many processed foods. Even ketchup contains HFCS.

When dietary modification is not enough to keep people gout free, drugs that block uric acid production or increase its elimination help. Ideally, uric acid levels should be in the range of 3-6 mg/dl. Diet is important not only for those who have suffered acute gout attacks, but also for those who have high uric acid levels without any symptoms. Hyperuricemia warrants a good look at the amount of dietary fructose.

Henry VIII’s confectionary was a clue to the relationship of girth to gout. As uric acid research progresses, blood tests for uric acid will probably become routine, because high levels often precede the development of high blood pressure and Type II diabetes, even in people not susceptible to gout.

Other Gout Facts

Many diuretics in common use raise uric acid levels and can trigger gout, especially the thiazide group.

Gout attacks commonly follow trauma or surgery because tissue breakdown produces purines.

Cancer treatments may also raise uric acid levels as tumor cells break down.

Uric acid levels increase in women after menopause and women rarely suffer from gout before then.

Uric acid levels in men rise at the time of puberty.

For the last half a century or more we have believed the dietary cholesterol theory about heart disease, a hypothesis (idea to be tested by experiment) that found favor with researchers, grant makers, doctors and drug makers. What if this theory is wrong? What if cholesterol in artery walls has less to do with dietary fat than with the way the body processes carbohydrates? What if refined sugars and grains are the dietary culprits? Could insulin, the master hormone at the center of all energy processing, be a better marker than cholesterol for heart disease?

What is blood sugar?

The first thing to understand about sugar is that the blood sugar is not the same thing as the sugar in your pantry. Or the sugar in soft drinks or the sugar in fresh fruit. Blood sugar is a simple molecule called glucose – a product of plants’ ability to convert the energy of the sun into starches, long chains of glucose linked together. When you eat a starch, the digestion process breaks down the chains into simple glucose molecules which circulate in your blood. Glucose is used by every cell in the body for energy, and is also made into glycogen for storage in liver and muscle.The sugar in your pantry is sucrose extracted from plants, specifically cane grasses and beets, by a refining process that concentrates and crystallizes it. Each sucrose molecule is a combination of one glucose molecule with another of fructose, a chemically different plant sugar molecule.

The taste for sweetness is innate and possibly addictive. Before the advent of refined sugar, indulging the sweet tooth was difficult. The only edible sources were berries and fruits and small amounts of honey guarded by nasty bees – all confined by climate and geography. Sugar made its way into the human diet slowly, spreading from the East to the West as the secret of this “liquid gold” made its way along routes of commerce.

Sugar and the diseases of civilization

With time and commerce, consumption of sugar and refined grains skyrocketed. The diseases of civilization – diabetes, heart disease and obesity – followed refined sugar, flour and rice around the world, appearing wherever old dietary staples were replaced by these “white” foods. By the 1920s, the Americans averaged 110-120 pounds of sugar per person per year. We inched up to 124 pounds by the late 1970s. Then came the Japanese chemical innovation that made high-fructose corn syrup (HFCS) a dietary staple. By 2000, HFCS bumped sugar consumption up to 150 lbs. per year, largely in the form of sweetened drinks.

High fructose corn syrup

HFCS differs from sucrose because the ratio of fructose to glucose in corn syrup is 10% higher than in table sugar – 55:45 instead of 50:50. Some scientists believe that it is the remarkable increase in fructose consumption in modern times that correlates with the appearance of the metabolic syndrome – abdominal obesity, high fasting blood sugar, high triglycerides, abnormal lipoprotein levels and high blood pressure. If so, a 10% increase in fructose combined with a recent, large jump in overall sugar consumption may spell real trouble.
How can fructose cause trouble? Isn’t it the primary sugar of fruits? Yes, but eating an apple with a small amount of fructose combined with absorption-slowing fiber hardly nudges blood sugar up – a far cry from the blood sugar spike after 20 ounces of an HFCS sweetened beverage. Drink a coke, and about 60% of the glucose in the HFCS goes directly into the blood for immediate use, and 40 % into the liver for storage as glycogen. The fructose all goes to the liver for conversion into fat – released into the blood as triglycerides. The higher the fructose in the diet, the higher the triglycerides in the blood. Fructose is a “lipogenic” or fat-producing sugar, and long term consumption also raises LDL or bad cholesterol.

The problems with too much sugar

Once sugar consumption exceeds the small amounts nature provides without refining techniques, trouble begins. The different ways the body processes fructose and glucose combine to produce very efficient fat production. A rise in blood glucose prompts the pancreas to put out insulin to help ferry glucose into cells for energy use or storage. Insulin, like fructose, is “lipogenic” because it helps move fats into storage depots in three areas – the liver, fat tissue, and the walls of arteries. And as triglycerides are formed from fructose, insulin busies itself shuttling them around the liver and out into the blood. The pancreas then produces even more insulin to take care of the glucose – this is the phenomenon known as insulin resistance, part of the metabolic syndrome associated with heart disease.

Is it the cholesterol or the sugar?

The theory that cholesterol in dietary fat is the direct cause of cholesterol deposits in arteries requires a leap over the metabolic pathways that process simple sugars and are intimately involved in fat formation and storage – and over the fact that many people with low cholesterol levels have heart disease. Over the last half century, many researchers and doctors made the leap because they believed the theory. Just as important to widespread acceptance, though, were less scientific influences like the cheap availability of a test for blood cholesterol, the difficulty and expense of measuring insulin, and the dominance of researchers devoted to the dietary cholesterol theory over those who questioned it.

Medical history books contain an embarrassing array of once-unassailable theories and practices that have fallen by the wayside. Despite a modern sense of scientific invincibility, current medical ideas are not immune from error. Sugar and refined carbohydrates are not yet the poster children for the scourge of heart disease, but they may be a far better target than cholesterol. If the dietary fat theory gives way to the sugar theory, the massive push to lower cholesterol by diet and drugs may go into the books as one of those once-unassailable ideas that eventually fell.

Posted by medical plaintalk

Posted by medical plaintalk