Got gout? Try milk -- or cherries
In 1842, the English writer Sydney Smith wrote, “Gout is the only enemy that I do not wish to have at my feet.”
Anyone who has suffered a painful attack of gouty arthritis would probably agree.
Gout is the result of an imbalance between the production and excretion of urate, the metabolic end product of dietary purines that are found in abundance in animal proteins.
If blood levels of urate rise high enough, the chemical can settle as crystallized deposits in joints. Most frequently, the big toe is affected -- becoming so swollen and sensitive that even the weight of a sheet or blanket on the area can cause excruciating pain.
Gout has a long history. It’s often called “the disease of kings and the king of diseases,” because in the past only the wealthy could afford to overindulge on purine-rich organ meats, gravies and seafood.
Most mammals have low blood levels of urate due to the activity of an enzyme, uricase, which converts urate into the more soluble chemical, allantoin. We humans are different. Millions of years ago, our hominoid ancestors experienced several mutations in the gene responsible for uricase, rendering it nonfunctional. Lacking the active enzyme, humans and great apes have higher urate levels than other mammals.
A research group at Baylor College of Medicine suggests that this genetic mutation may have helped ancient humans survive. Elevated urate levels increase salt sensitivity, helping to maintain blood pressure when the sodium content of the diet is low. And although we may be swimming in salt today, it’s been estimated that the fruit- and leaf-based diet of our ancestors a million years ago supplied a paltry 225 milligrams to 700 milligrams of sodium per day.
But a chronically high urate level is a disadvantage to the average American today, who consumes a whopping 4,000 milligrams of sodium daily. It contributes to hypertension, which is often seen in association with gout.
Not surprisingly, diets rich in animal protein increase the risk of gout, which strikes seven to nine times more males than females. So does high alcohol intake and obesity. In parallel with rising obesity rates, the prevalence of the disease has doubled over the last twenty years.
Because of this strong relationship, the primary emphasis of dietary treatment for gout is placed on weight reduction and less on drastically slashing purine intake. Low purine diets are quite limiting (animal proteins, many vegetables, whole grains and beans are restricted) and thus can be hard to follow. They’re also only moderately effective in lowering blood urate levels because most gout sufferers are poor urate excreters.
However, a balance of animal and plant protein sources (and moderation of beer and hard alcohol consumption) are still advisable as part of the overall treatment plan.
Sometimes dairy foods, which are naturally low in purines, are recommended: These induce excretion of urate in the urine and also reduce the overall quantity of purine in the diet when substituted for higherpurine proteins.
Cherries have had a long-standing reputation for controlling the inflammation associated with gout. The reported benefits have been largely anecdotal, but in 2003 a clinical study of 10 healthy women, published in the Journal of Nutrition, confirmed that after a single serving of about 45 Bing cherries, blood urate levels decreased significantly for five hours. Similar doses of grapes, strawberries or kiwifruit had no effect.
A recent report published in Arthritis and Rheumatism in June evaluated the relationship between coffee intake and the risk of gout in a large group of 45,000-plus men followed for more than 12 years. Compared with men who never drank coffee, the risk of developing gout was 40% lower for men who drank four to five cups a day, and 59% lower for those who drank six or more cups.
Since the levels of caffeine intake weren’t associated with gout incidence, the researchers speculate that other components in coffee -- chlorogenic acid, a strong antioxidant -- may be responsible for the benefit.
Nearly 400 years ago, when gout had reached epidemic proportions in England, the philosopher (and gout sufferer) John Locke encouraged milk drinking and “eating very little flesh but abundance of herbs.”
Future research will undoubtedly help to refine the dietary recommendations for gout sufferers -- but this ancient wisdom still rings true.
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Susan Bowerman is a registered dietitian and assistant director of the UCLA Center for Human Nutrition.
