Correlations are not causes

Consider the following possibilities:

  1. Higher organisms have better DNA repair and live longer than lower organisms. A correlation exists but it is neither causal nor contributory (neither a major nor a minor contributor).
  2. Higher organisms have better DNA repair than lower organisms, and in part because of this, live longer. Better DNA repair contributes to or drives (is the major contributor to) greater longevity.
  3. Higher organisms have better DNA repair than lower organisms, and solely because of this, live longer. Better DNA repair is the sole cause of their greater longevity. DNA damage is solely responsible for senescence and death.

Of the three possibilities listed, #2 is the most likely. The effect on longevity might be small, medium, or large. The best experiment is hard to do:

  1. Create a sufficiently large cohorts of different types of higher organisms whose DNA repair is no better than that of a mouse, and compare their longevity with mice and with other members of the higher species whose DNA repair is wild type. If possible, change nothing else. Of course, it is not possible to change nothing else. Intrinsic complexity rules! Interpretations are always suspect even when most people think they are crystal clear.
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Rule: Correlations are not causes

Hyperuricemia correlates most strongly with gout and less strongly with a number of other medical conditions, including elevated BP and elevated blood sugar.

Is hyperuricemia the cause of any of them?

No – but the underlying problems, kidney and liver insufficiency, are contributors to all of them.

Kidney and liver insufficiency are short of outright diseases and are more common than outright diseases.

A healthy liver balances the toxic loads on the body. It directs a portion of the toxins toward the circulatory system, the kidneys, the ureters, the bladder, and the urethra, and each of these things suffers the consequences, depending roughly on the product of the toxicity per unit concentration, the concentration of the toxins, and the time spent in contact with these organs/tissues. The liver directs the rest of the toxins to the gall bladder, which stores and concentrates the toxins, taking a real beating, to the small intestine, large intestine and the anus. Nothing gets the full load of toxicity that the liver was processing.

Any degree of liver insufficiency can increase total toxicity and exacerbate problems with the body’s management of total toxic loads and especially unbalanced toxic loads,

Kidney insufficiency increases the concentration of a large number of circulating toxins, and of some nutrients (the kidneys do not ordinarily reabsorb 90% of toxins; they do ordinarily reabsorb 90% of uric acid in the filtrate, consistent with uric acid being a nutrient, whose concentration in blood will rise when kidney filtration is subpar), like uric acid, and thus all sorts of medical conditions will correlate with kidney insufficiency. It is a real problem, a real menace to health.

High circulating uric acid, due mostly to kidney insufficiency, increases the odds of gout. But gout starts long before that with the development of an arthritic joint, itself a long and complicated tug of war process, followed by some kind of injury (like stubbing the toe), or insult (a recent surgery), or an infection in or near the joint, (could mild acidification of the joint be a common denominator in these triggers?) and given kidney insufficiency, too high a concentration of uric acid increases the odds of an acute gouty attack, most often in one synovial joint of one big toe.