Fruit is the friendliest food group in the oxalate table: the large majority of fresh fruits measure between 0 and 6 mg per serving, and several sit at literal zero. But the group has exceptions that surprise people — a few fruits climb into double digits, dried versions concentrate everything, and one tropical fruit is a hard stop for anyone with reduced kidney function. Here is the measured map of the whole group.
| Food | Oxalate (mg) | Serving | Rating |
|---|---|---|---|
| Apple, fresh | 1-5 mg | 1 medium | Safe |
| Banana | 3-6 mg | 1 medium | Safe |
| Watermelon | 1-2 mg | 1 cup cubes | Safe |
| Peaches, fresh or canned | 0-3 mg | 1 fruit | Safe |
| Mango | 1-7 mg | 1 cup | Safe |
| Pears | 2-7 mg | 1 fruit | Safe |
| Strawberries | 2-6 mg | 1/2 cup | Safe |
| Melons (cantaloupe, honeydew) | 1-2 mg | 1 cup | Safe |
Eight fruits a stone-former can eat without arithmetic. They also carry fluid and potassium — the two columns that help — which makes the fruit bowl the easiest yes in the entire oxalate table. Two portions of any of these plus the rest of a normal day stays far under a conservative budget.
The middle band — pineapple (~4-8 mg), cherries (~2-6 mg), grapes (~3 mg), limes and lemons (~1-4 mg, with the citrate bonus) — still fits easily. The watch list is short: kiwi (~27 mg), blackberries (~45 mg per cup), raspberries (~21 mg), oranges (~14-18 mg), and every dried fruit, where a half cup concentrates multiple whole servings of fruit. Dried figs, dried pineapple, and prunes are the highest-energy items in the fruit aisle for oxalate.
Two fruits deserve their own warning labels. Rhubarb is the extreme — over 500 mg per serving by Harvard's measurement, in the spinach league. And star fruit (carambola) carries a toxin that damaged kidneys cannot clear; it is a documented cause of neurologic crises in kidney patients, which is a categorically different concern than oxalate arithmetic — anyone with reduced kidney function should avoid it outright.
Three practical lines. Build the daily fruit intake from the free tier — eight fruits, no arithmetic, real potassium and water. Treat dried fruit as a condiment rather than a snack, since a half cup can carry five fresh servings' load. And keep the two warnings in circulation at home: rhubarb with the spinach-level numbers, and star fruit for any household member watching their kidneys for a different reason.
See how oxalate values are measured and verified on our data methodology page.