Gout

I hate to admit it, but there are some potential downsides to the low-carb diet. One of them is an increased risk of gout. Gout is not life-threatening, but I'm here to tell you, it's painful. I first got it many years ago, long before I had even heard of low-carb diets, but once you get it you're far more prone to it thereafter.

It's caused by a buildup of uric acid crystals in the joints. These things hurt. The joint becomes stiff and swollen, probably due to tissue damage caused by the crystals. This might explain why it has such a strong tendency to return once you've had it: to oversimplify, you now have uric-acid-crystal-shaped holes in the tissues where the crystals can easily reform under the right conditions.

The traditional treatment is a diet low in purines (a class of organic compound of which our reviled uric acid is a member), which by definition is a diet high in carbohydrates.  This is also effective at preventing it in the first place.  The "perfect storm" created by the low-carb diet is a consequence of first being very high in purines, and second, diminishing the ability of your kidneys to eliminate uric acid, leading to buildup and crystalization under some circumstances.

It's been known for a long time that it's not the ketosis that sets this up, but the large amount of fat in the diet.  Now, while eating a low-carb, high-fat diet does increase your risk of experiencing this unpleasantness, it's still relatively uncommon.  That's because other contributing factors seem to be required, and there are a lot of things that help protect against it.  For example, if you're getting plenty of fluids, your kidneys are generally active enough to get rid of the excess uric acid produced by your diet.  And if you're getting plenty of exercise, the crystals likely won't have a chance to form in the joints in the first place.

There also seem to be some specific foods you can consume to lower your risk.  Dairy products, for example, tend to decrease the amount of uric acid in your blood.  Coffee has been shown to decrease your risk of getting gout in the first place, but no one seems to know why.  Anecdotally, I'm pretty sure I can vouch for coffee as an effective treatment and preventative even after getting it, and this is possibly explained by the effects of caffeine on uric acid levels.

And still other foods further increase your risk.  These include organ meats such as liver and kidneys, which are very high in purines, and alcohol.  The flare-up I'm presently suffering from happened to occur after an expense-account night at the bar, but I'm sure that's completely unrelated.

This is the first of a short list of "gotchas" that I'll be covering.  The takeaway lesson?  More dairy products, more coffee, less alcohol.  Milk, by the way, has lactose, a sugar that's not compatible with a low-carb diet in high doses, so I recommend regular coffee with lots of heavy cream for two powerful nearly-carb-free preventatives at once.