Oxalates In Tea: Concern or Not?
Got kidney stones? Diagnosed with hyperoxaluria? Reducing your consumption of foods high in oxalates may be necessary. The first step is a 24-hour urine test for oxalates and a consultation with your medical practitioner. If there is a concern, you may need to eat less chocolate, nuts, green leafy veggies like kale, chard or spinach, berries, and our favorite beverage, Camellia sinensis.
Are Teas a Concern for Oxalates?
The answer is “probably not.” True teas fall into Group 2 of oxalate plants, those that contain far less than Group 1 produce like rhubarb or spinach which are highest in oxalates. For example, a cup of brewed black tea could range from 2.98 milligrams to 15.61 milligrams of oxalate acid; a 100 gram serving of spinach contains a whopping 970 milligrams.
NOTE: As shocking as this comparison may be, it’s important to remember that the valuable nutrients in greens like spinach or other produce are important to include in a healthful diet yet they must be managed by consuming modest portions. Eating ½ to 1 ½ cups cooked greens or 1 to 3 cups raw greens per day would be ideal and rarely make any serious impact on one’s health. A person would have to consume 16 cups of spinach a day to seriously impact one’s oxalate levels or become vulnerable to kidney stones.
Overall, the flavonoids, catechins, and other healthful elements in true teas and Rooibos far outweigh any concerns for oxalates because they appear in tiny quantities.
Tea Types Matter
Processing teas as black also elevates oxalates, so if oxalates are a concern, always add milk or cream to your black teas.
Greens and oolongs contain much less oxalate acids. In fact, green teas average only 2.36 milligrams per cup; oolongs have .58 milligrams per cup, and herbals about .84 milligrams of oxalates per cup; all modest amounts and rarely of concern to healthy adults.
Japanese teas which are shaded like Tencha and Gyokuro, contain more oxalates than Sencha, Genmaicha, or Hojicha. The shading used for the premier Japanese greens increases the chlorophyll for both taste and appearance and that process also increases the oxalate activity slightly. The one exception for high oxalates in Japanese green teas is Matcha so it should be consumed in moderation if oxalates are a diet concern.
What About Herbals?
Herbal teas made from fruits are a concern only for those people susceptible to developing kidney stones. Also, be aware that brewing herbals in hot boiling water greatly reduces the oxalic acid because the addition of water dilutes the full dose of oxalates.
The fruity herbals that are concerning for those sensitive to oxalates are berries like blueberries, raspberries, and strawberries; apricots, pineapples, and black currants plus nuts and ginger. Oranges, and peels from lemons and oranges, should also be avoided.
Some herbal brews are ideal for anyone, including those with oxalate sensitivity: Rooibos (green or red); honeybush, lavender, spearmint, chamomile, peppermint, and hibiscus.
Final Words
To sum, oxalic acids or oxalates appear naturally in most fruits and vegetables, teas, and herbals and are easily digested by most people. The only way to determine oxalate sensitivity is through a medically-supervised urine test and other medical consultation. Unless you have been diagnosed with kidney stones or renal health issues, please drink a cup or two of your favorite teas or herbals with enthusiasm and joy.