Physicians routinely see elevated uric acid levels in gout patients. Crystals of uric acid form if uric acid levels rise too high. These crystals tend to deposit themselves in the large joint of the big toe. Once there they produce inflammation and pain. Before the advent of modern drugs the only way to treat gout was with a low purine diet.
Purines are a type of protein found in a variety of vegetables and meats.
Since purines are converted into uric acid, patients with gout are frequently prescribed a diet that excludes these purine rich foods. Those that have inherited a Mixed or Hunter-gatherer metabolism will show relatively low uric acid values. These types of metabolism actually use purines as a required intermediate in the production of energy. Mixed and Hunter-gatherer metabolisms burn the great majority of purines that they consume and excrete the rest as uric acid. Agriculturists are metabolically built so that they can only utilize very small amounts of purines.