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.