Xanthines are produced by all human cells, as well as by certain plants and animals. You can find them in coffee, tea, chocolate products and anything caffeinated because caffeine is a type of xanthine. These substances may have some health benefits, although research on this is still in the preliminary stages. If you need to watch your purine intake, however, you'll want to limit xanthines in your diet because they're a type of purine.
Xanthines in Coffee and Other Caffeinated Foods
If you opt for caffeinated coffee, you'll get some xanthines in your beverage because caffeine is one of the three main types of xanthines. Too much caffeine can cause an increased heart rate, trouble sleeping, headaches, depression, nausea, tremors and increased urination, so stick to a moderate amount of caffeine, or about 200 to 300 milligrams per day, recommends MedlinePlus. This is the amount in two to three 8-ounce cups of coffee. A moderate amount of caffeine may help you limit your risk of Parkinson's disease, Alzheimer's disease, dementia, suicide, stroke and oral cancer, according to an October 2013 article on the AARP website.
Any food or drink containing caffeine provides xanthines. This means colas and other caffeinated soft drinks, energy drinks and gums and snacks with added caffeine are all sources of xanthines. Some pain relievers, cold medications and diet pills also provide caffeine.
Xanthines in Tea
Tea contains the xanthines caffeine and theophylline, but isn't a good source of theobromine, the third main type of xanthine. Theophylline may help treat asthma and other respiratory diseases, according to a review article published in Food Research International in 2009. It helps relax and open your airways so you can breathe better. Due to the relatively small amounts of xanthines in tea, you'd need to drink between 2 and 10 cups per day to reap the potential respiratory health benefits.
Keep in mind that herbal teas and rooibos do not come from the Camellia sinensis plant and thus don't contain xanthines. Mate tea, however, contains a significant amount of caffeine and also contains some theobromine, even though it isn't a "true" tea, so it's another source of xanthines.
Xanthines in Chocolate
Chocolate contains both caffeine and theobromine. A review article published in The FASEB Journal in November 2004 noted that theobromine may help to relieve coughing, but the evidence for this is still preliminary. Unlike caffeine, theobromine may contribute to a better night's sleep, according to a review article published in Nutrients in October 2013. The darker the chocolate, the more caffeine and theobromine it contains.
People who have gout or kidney stones are sometimes put on a low-purine diet to limit the formation of uric acid, which can worsen these conditions. The total amount of purines found in coffee, tea and hot chocolate is small enough that the University of Pittsburgh Medical Center permits them on a low-purine diet, but doesn't recommend chocolate due to its high fat content.