Humans and Gorillas Can Get Gout, But We Can Both Get By With Very Little Salt!

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Gouty arthri­tis results from the buildup of crys­tals of uric acid in the joints.

Peo­ple who eat a lot of meat are at risk for gout—one of the most painful con­di­tions known to med­ical sci­ence. Gout results when crys­tals of a uric acid salt build up in the joints. These crys­tals can also build up in the uri­nary sys­tem, pro­duc­ing kid­ney stones—another of the most painful con­di­tions known to med­ical sci­ence. A recent the­o­ry sug­gests that our high risk for gout is a side effect of an adap­ta­tion that enabled human beings, goril­las, and the oth­er great apes to sur­vive a short­age of sodi­um.

Although eat­ing meat and seafood caus­es gout in peo­ple, it doesn’t cause gout in a nat­ur­al car­ni­vore like a cat. That’s because cats, like most mam­mals, pro­duce an enzyme called uri­c­ase, which breaks uric acid down into some­thing that dis­solves eas­i­ly in water and pass­es right out through the kid­neys. Human beings and the great apes are prac­ti­cal­ly the only mam­mals that can’t make uri­c­ase. This fact sug­gests that peo­ple, like goril­las, should prob­a­bly be eat­ing a high­ly plant-based diet.

In the wild, apes are free from gout because their plant-based diet is low in purines, which the body con­verts to uric acid. Fruit and veg­eta­bles are also mild­ly alka­lin­iz­ing, and the mild meta­bol­ic alka­lo­sis enables the blood to keep more uric acid dis­solved. So the great apes can live gout-free even though they can’t make uri­c­ase. Sim­i­lar­ly, human beings can avoid gout sim­ply by eat­ing a plant-based diet with a heavy empha­sis on fruit and veg­eta­bles.

It’s sur­pris­ing that human beings and the great apes can’t make uri­c­ase. We’re prac­ti­cal­ly the only mam­mals that don’t. The gene for uri­c­ase has sur­vived almost unchanged through hun­dreds of mil­lions of years of evo­lu­tion. That’s gen­er­al­ly a sign that the gene does some­thing impor­tant. Yet the lack of uri­c­ase might actu­al­ly be an advan­tage for wild apes. The extra uric acid in their blood might enable them to sur­vive on a diet that would oth­er­wise be dan­ger­ous­ly low in sodi­um.

As we’ve seen, goril­las eat a very low-sodi­um diet. Meat-eaters don’t run a risk of sodi­um defi­cien­cy, because meat and oth­er ani­mal-based foods are high in sodi­um.

Gout Hurts!

Gout is one of the most painful con­di­tions known to med­ical sci­ence. As you can see in this 1799 car­toon by James Gill­ray, a gout suf­fer­er, gout tends to strike the big toe. Back then, gout was a dis­ease of the rich, who could afford to eat lots of meat and drink lots of booze.

Another cartoon by gout sufferer James Gillray.
Anoth­er car­toon by gout suf­fer­er James Gill­ray.

Gout results from the buildup of crys­tals of uric acid in the joints. Some­times, this buildup can be very severe. If you want to see how bad it can get, click here.

The good news is that gout can be pre­vent­ed and treat­ed by prop­er diet. Sci­en­tists have known for cen­turies that gout results from eat­ing too much meat. Gout is com­mon in the Unit­ed States but is vir­tu­al­ly unknown in soci­eties where peo­ple eat a starchy, plant-based diet. The best way to pre­vent and con­trol gout is to cor­rect the diet. One word of cau­tion: rapid weight loss, even from a switch to a healthy diet, can trig­ger an attack of gout, because of the sud­den release of uric acid result­ing from the loss of body fat.

In an upcom­ing post, I’ll explain why peo­ple get gout, why goril­las could but don’t get gout, and why real car­ni­vores like dogs and cats and real omni­vores like rats can’t get it.