|
What are Purines? Purines are nucleotide bases found in plant and animal cells. Purines comprise adenine, guanine, hypoxanthine, and xanthine. They make up important components of the genetic materials, DNA and RNA, and energy molecules such as ATP, GTP and coenzyme A. Therefore, purines are essential constituents of life. Purine Rich Diet and Gout In the body, purines are metabolized to uric acid, for instance when cells die. Purines are among the factors that are causes of elevated uric acid in the blood. With the consumption of high purine foods, serum uric acid may rise above the normal level. Even though uric acid acts as an antioxidant and has a free-radical scavenging effect, when it accumulates to a high level in the blood it can cause gout and other health problems. Gout is a form of arthritis caused by the accumulation of uric acid in joints, especially in the big toe. In a 12-year study that followed eating habits and gout incidence in large number of men it was found that eating food rich in purine, such as meat and seafood, was associated with high risk of gout, whereas a higher level of consumption of dairy products was associated with a reduced risk. Moderate intake of purine-rich vegetables or protein was not associated with an elevated risk of gout. Food High or Low in Purines In the following table are estimates of purine content in a variety of food items. Purine rich foods are on the top of the table. Meat and meat products appear to have high total purine content, where as cereal foods contain low purine content. Generally, there seems to exist a positive association between protein and purine content in diet. Table 1: High or low purine food sources | Food Sources of Purine | Total purine content (mg of purine/100 g food) | | Liver | 286.4 | | Kidney | 230.8 | | Poultry | 130.7 | | lamb, roasted, chop | 127.5 | | Pork, roasted, chop | 119.0 | | Fish, white, fresh | 115.9 | | Mushroom, fresh | 46.9 | | Bread, crusted | 15.7 | | Bread, white | 12.2 | | Wheat flour | 11.5 | | Cottage cheese | 8.0 | | Plain yogurt | 7.0 | | Rice, cooked | 5.9 | Table 2: Purine content in meat organs, seafoods (fresh and canned), and vegetables (legumes). | Purine food sources | Total purine content (mg/100 gram food) | | Organ meats | Total purines | | Pork liver | 289 | | Chicken liver | 243 | | Chicken heart | 223 | | Beef kidney | 213 | | Beef liver | 197 | | Beef heart | 171 | | Lamb heart | 171 | | Beef brain | 162 | | Lamb liver | 147 | | | | | Fresh seafoods | | Anchovies | 411 | | Sardines | 345 | | Salmon | 250 | | Mackerel | 194 | | Clams | 136 | | Squid | 135 | | Canned seafoods | | Sardines | 399 | | Herring | 378 | | Anchovies | 321 | | Mackerel | 246 | | Shrimp | 234 | | Tuna | 142 | | Oysters | 107 | | Salmon | 88 | | Clams | 62 | | Dried legumes | | Blackeye peas | 230 | | Lentils | 222 | | Great northern bean | 213 | | Small white bean | 202 | | Split peas | 195 | | Pinto bean | 171 | | Red bean | 162 | | Large lima bean | 149 | | Baby lima bean | 144 | | Cranberry bean | 75 | | Garbanza bean | 56 | According to a study that compared free and total purine bases content in meat products (steak, beef liver and haddock fillets) before and after cooking, cooking appears to increase the level of free and total purine bases in a diet. Total purine content is based on the sum of all the four purine bases. Table 3: Purine content in raw and cooked foods. | Meat products | Total purine content (mg of purine/food) | | Liver, raw | 202.2 | | liver, boiled | 237.0 | | liver, broiled | 236.1 | | Steak, raw | 105.9 | | Steak, boiled | 107.8 | | Steak, broiled | 121.0 | | Haddock, raw | 101.7 | | Haddock, boiled | 94.7 | | Haddock, broiled | 118.7 | Table 4: Purine content in chicken parts (listed high to low). | Purine sources | Total purine content (mg of purine/food) | | Liver, chicken | 236.1 | | Drumstick, chicken | 132.3 | | Breast, chicken | 130.7 | | Gizzard, chicken | 130.5 | | Thigh, chicken | 126.5 | | Skin, chicken | 104.6 | Alcohol drinks also contain purines. There is strong association between high consumption of alcoholic drinks and uric acid levels in the blood, and consequently gout. Below are estimates of purine content in alcoholic drinks analysed by British researchers. Table 5: Purine content in alcoholic drinks (beer). | Alcohol drink | Total purine content (mg of purine/Litre) | | Traditional British beers | 20.3 - 27.5 | | Guinness | 23.8 | | Lager beer | 17.7 | | Home-brewed beer | 3.9 | | Cider | 0.4 | More on gout and diet: Gout causes, diagnosis, symptoms, and cure
Food high/low in uric acid
Gout Causes: Food High in Purines and Uric Acid, and Alcohol
Gout and diet: Serum uric acid level and coffee and tea intake
Low purine diet cookbooks and gout related books
Blood uric acid, cardiovacular disease and diabetes:
Uric acid, cardiovascular disease and diabetes mellitus
uric acid, background
Serum uric acid, hypertension and metabolic syndrome
Serum uric acid, obesity and hyperglycemia
Serum uric acid and antioxidant or pro-oxidant activity
Serum uric acid, inflammation and renal disease
Hyperuricemia and nutritional approach References: Brule, D. Sarwar, G., and Savoie, L. 1988. Purine content of Selected Canadian Food Products. Journal of Food Composition and Analysis 1(2): 130-138.
Brule, D., Sarwar, G. and Savoie, L. 1989. Effects of methods of cooking on free and total purine bases in meat and fish. Can. Insti. Food Sci. Technol. J. Vol. 22(3): 248 - 251.
Choi, H. K., Atkinson, K., Karlson, E. W., Willett, W., and Curhan, G.. 2004. Purine-Rich Foods, Dairy and Protein Intake, and the Risk of Gout in Men. The New England Journal of Medicine, Vol. 350(11):1093-1103.
Clifford, A. J. and Stroy, D. L. 1976. Levels of purines in foods and their metabolic effects in rats. Journal of Nutrition 106: 435-442.
Gibson, T., Rodgers, A. V., Simmonds, H. A. and Toseland, P. 1984. Beer drinking and its effect on uric acid. British Journal of Rheumatology, 23: 203 - 209.
Young, L. L. 1980. Evaluation of four purine compounds in poultry products. Journal of Food Science 45: 1064-67. |
