Saturday, March 19, 2011

Gout and Carbs - Taubes Via Ferriss

This is like so many of the other stories in Good Calories Bad Calories - it just makes you shake your head that it happened this way.  If this summary is correct - perhaps there's someone in our audience that can refute it - the path of treatment over the last 30 to 40 years is astonishing.

If you don't have gout, be thankful, and if you do have gout, this excerpt will provide an easy blueprint for how to avoid it.

What is gout?
The pathology of gout has been understood since the British physician Alfred Garrod, in the mid-19th century, identified uric acid as the causative agent; the idea being that uric acid accumulates in the circulation to the point that it falls out of solution, as a chemist would put it, and so crystallizes into needle-sharp urate crystals. These crystals then lodge in the soft tissues and in the joints of the extremities – classically, the big toe — and cause inflammation, swelling and an excruciating pain that was described memorably by the 18th century bon vivant Sydney Smith as like walking on one’s eyeballs.(3)

So how should gout be treated?
Because uric acid itself is a breakdown product of protein compounds known as purines – the building blocks of amino acids – and because purines are at their highest concentration in meat, it has been assumed for the past 130-odd years that the primary dietary means of elevating uric acid levels in the blood, and so causing first hyperuricemia and then gout, is an excess of meat consumption.
The actual evidence, however, has always been less-than-compelling: Just as low cholesterol diets have only a trivial effect on serum cholesterol levels, for instance, and low-salt diets have a clinically insignificant effect on blood pressure, low-purine diets have a negligible effect on uric acid levels. A nearly vegetarian diet, for instance, is likely to drop serum uric acid levels by 10 to 15% percent compared to a typical American diet, but that’s rarely sufficient to return high uric acid levels to normality, and there is little evidence that such diets reliably reduce the incidence of gouty attacks in those afflicted.(4) Thus, purine-free diets are no longer prescribed for the treatment of gout, as the gout specialist Irving Fox noted in 1984, “because of their ineffectiveness” and their “minor influence” on uric acid levels.(5) Moreover, the incident of gout in vegetarians, or mostly vegetarians, has always been significant and “much higher than is generally assumed.”

So What Does Work To Treat Gout?
The short answer is, a carb restricted diet, and especially a diet very low in fructose.
...eating more protein increases the excretion of uric acid from the kidney and, by doing so, decreases the level of uric acid in the blood.(7)  The alternative hypothesis is suggested by the association between gout and the entire spectrum of diseases of civilization, and between hyperuricemia and the metabolic abnormalities of Syndrome X. In the past century, gout has manifested all of the now-familiar patterns, chronologically and geographically, of diseases of civilization, and so those diseases associated with western diets.
...a series of studies in the 1960s, as clinical investigators first linked hyperuricemia to glucose intolerance and high triglycerides, and then later to high insulin levels and insulin resistance.(14) By the 1990s, Gerald Reaven, among others, was reporting that insulin resistance and hyperinsulinemia raised uric acid levels, apparently by decreasing uric acid excretion by the kidney, just as they raised blood pressure by decreasing sodium excretion. “It appears that modulation of serum uric concentration by insulin resistance is exerted at the level of the kidney,” Reaven wrote, “the more insulin-resistant an individual, the higher the serum uric acid concentration.” (15)
...simply put, fructose increases serum levels of uric acid. The “striking increase” in uric acid levels with an infusion of fructose was first reported in the Lancet in the late 1960s by clinicians from Helsinki, Finland, who referred to it as fructose-induced hyperuricemia.(20) This was followed by a series of studies through the late 1980s confirming the existence of the effect and reporting on the variety of mechanisms by which it came about. Fructose, for instance, accelerates the breakdown of a molecule known as ATP, which is the primary source of energy for cellular reactions and is loaded with purines. (ATP stands for adenosine triphosphate; adenosine is a form of adenine, and adenine is a purine.) And so this in turn increases formation of uric acid. Alcohol apparently raises uric acid levels through the same mechanism, although beer also has purines in it.(21) Fructose also stimulates the synthesis of purines directly, and the metabolism of fructose leads to the production of lactic acid, which in turn reduces the excretion of uric acid by the kidney and so raises uric acid concentrations indirectly by that mechanism.(22)
These mechanistic explanations of how fructose raises uric acid levels were then supported by a genetic connection between fructose metabolism and gout itself. Gout often runs in families, so much so that those clinicians studying gout have always assumed the disease has a strong hereditary component. In 1990, Edwin Seegmiller, one of the few veteran gout researchers in the U.S., and the British geneticist George Radda, who would go onto become director of the Medical Research Counsel, reported that the explanation for this familial association seemed to be a very specific defect in the genes that regulate fructose metabolism. Thus, individuals who inherit this defect will have trouble metabolizing fructose and so will be born with a predisposition to gout.
...sugar (sucrose) and high fructose corn syrup would constitute the worst of all carbohydrates when it comes to uric acid and gout. The fructose would increase uric acid production and decrease uric acid excretion, while the glucose, though its effect on insulin, would also decrease uric acid excretion. Thus, it would be reasonable to assume or at least to speculate that sugar is a likely cause of gout, and that the patterns of sugar consumption explain the appearance and distribution of the disease.
This is another potentially harmful effect of fructose that post-dates the official reports exonerating sugar in the diet. And it is yet another mechanism by which sugar and high fructose corn syrup could be a particularly unhealthy combination. The glucose in these sugars would raise insulin levels, which in turn would raise blood pressure by inhibiting the kidney’s secretion of sodium and by stimulating the sympathetic nervous system, as we discussed in an earlier chapter, and the fructose would do it independently by raising uric acid levels and so damaging the kidney directly. If this were the case, which has never been tested, it would potentially explain the common association of gout and hypertension and even of diabetes and hypertension.(31)

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