Purines are a type of chemical compound found in foods and drinks that are part of a normal diet. A small number of foods contain concentrated levels of purines, such as seafood, organ meats and alcoholic beverages, especially beer.
People who have trouble metabolizing purines, such as people with hyperuricemia or gout, are advised to limit consumption of these foods.
Purines Are in All Living Things
Purines can be found in the nucleus of any plant or animal cell. The name "purines" refers to a specific type of molecule made up of carbon and nitrogen atoms, and these molecules are found in cells' DNA and RNA.
Essentially, purines are the building blocks of all living things. In the human body, purines can be divided into two categories:
- Endogenous purines that are manufactured by the body
- Exogenous purines that enter the body via food
Exogenous purines, the purines that a person eats, are metabolized by the body. Specifically, the liver breaks down the purines and produces a waste product called uric acid. The uric acid is released into the bloodstream and is eventually filtered by the kidneys and excreted in the urine.
If too much uric acid builds up in the bloodstream it is called hyperuricemia. In some people, hyperuricemia can cause kidney stones or lead to an inflammatory joint condition called gout. Other people have absolutely no symptoms of high uric acid levels, and they are referred to as "asymptomatic."
People with hyperuricemia are encouraged to eat foods with low purine concentrations and avoid foods with high purine concentrations. In addition, foods and drinks that inhibit the body's ability to metabolize purines, such as alcohol and saturated fats, should be limited or avoided altogether.
The table below shows foods that have relatively high, moderate and low concentrations of purines.
|High Purine Foods||Moderate Purine Foods: Eat Limited Quantities||Low Purine Foods|
|Meats, especially organ meats or "sweetmeats," such as liver, brains, and beef kidneys, as well game meats, such as venison, which are typically fatty||Certain vegetables, including asparagus, spinach, mushrooms, green peas and cauliflower (no more than ½ cup per day)||Any vegetables that are not listed as moderately high in purines, such as leafy greens, carrots and tomatoes|
|Foods containing saturated fats: these tend to inhibit the body's ability to metabolize purines||Beef, pork, lamb, fish and poultry (no more than 4-6 oz daily)||Condiments that contain oils, spices, and vinegars are generally acceptable|
|Seafood, particularly scallops and other shellfish, anchovies, sardines, herring, and mackerel||Wine* (1-2 glasses, when gout symptoms are absent)||Rice, enriched pastas and breads, potatoes, and popcorn|
|Foods and drinks made with high fructose corn syrup, such as sodas1||Wheat bran and wheat germ (1/4 cup dry daily)||Nuts and nut products, such as peanut butter|
|Supplements containing yeast or yeast extract||Dried beans, lentils and peas (1 cup cooked)||Dairy products (preferably low- or no-fat)|
|Gravy||Oatmeal (2/3 cup dry daily)||Eggs, particularly egg whites|
|Beer*||Fruit juice (no corn syrup)||Coffee and tea|
|Meat-based soup stocks||Fruits|
*Alcoholic drinks can inhibit the body's ability to eliminate uric acid, so people with gout are advised to avoid alcohol or drink in moderation. Beer is notorious for bringing on gout attacks because it contains both alcohol and brewers yeast, which is high in purines.
People on a low-purine diet should drink plenty of water to aid with digestion and lower uric acid concentrations in the blood.