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Draft: not yet reviewed by a clinician

Use this page to prepare questions for your care team. It does not replace their advice. Your own targets and doses come from your nephrologist, diabetes team and renal dietitian.

Potassium

In short

Potassium keeps your nerves, muscles and heart rhythm working. Healthy kidneys remove most of the potassium you eat, so as kidney function falls, blood potassium can rise. A very high level can cause a dangerous heart rhythm (KDIGO 2024). Only limit potassium if your blood potassium is high; your care team sets the number (KDOQI 2020, statement 6.4.1). When a limit is needed, the biggest wins are portion size, processed foods with potassium additives, and a few very high foods such as bananas, potatoes, tomato sauce and orange juice.

Your numbers

Starting points, not your prescription

These numbers are typical starting points from guidelines. Your nephrologist, diabetes team and renal dietitian set your own numbers from your blood tests, urine output and medicines, and change them as your labs change. If your lab report or your team says something different, they win.

Blood potassium is the same number in mmol/L and mEq/L, so one table covers both unit systems.

Typical
Blood potassium about 3.5–5.1 mmol/L (= mEq/L); your lab's range wins (MedlinePlus)
High (hyperkalemia) above 5.0–5.5 mmol/L
Call your team today 6.0–6.4 mmol/L; if you feel unwell, get checked in hospital now (KDIGO 2024, Table 28)
Emergency 6.5 mmol/L or more (KDIGO 2024, Table 28)
Food, when a limit is ordered usually 2,000–3,000 mg a day; AKF suggests aiming for 2,500 mg and no more than 3,000 mg (AKF; DaVita)
Peritoneal dialysis often 3,000–4,000 mg; some people run low and need more (DaVita)
The app's starting ceilings 4,000 mg (stages 1–3a), 3,500 (3b), 3,000 (4), 2,500 (5 and hemodialysis), 3,500 (peritoneal dialysis): review ceilings, not prescriptions

Why it rises. In people with diabetes, high potassium affects 8.8 % at stage G3 with little albumin in the urine and 34.4 % at G5 with a lot (KDIGO 2024, Figure 30). Food is only one cause. Not enough insulin, high blood glucose, ACE inhibitors and ARBs, finerenone, constipation and acid build-up push it up too (KDIGO 2024; Sousa 2016). So a run of high glucose readings, a missed basal insulin dose, or a new blood-pressure or kidney-protecting medicine is a reason to be stricter that week and to expect a blood test (KDIGO 2022). High glucose or a missed basal dose also means checking ketones and following your sick-day plan. See Blood potassium.

How much is in a serving

Per serving you actually eat Potassium
Low (AKF) 150 mg or less
Medium (AKF) 151–250 mg
High (AKF) 251 mg or more
High (NKF) 200 mg or more

(AKF potassium guide; NKF; NKF's shopping cue is 200 mg or less per serving, NKF label guide.) The app marks a single food "medium" at 101–200 mg and "high" above 200 mg.

Portion size matters most. "A large amount of a low-potassium food can easily turn it into a high-potassium food" (NKF). Half a cup of cantaloupe is about 214 mg; a full cup is 427 mg (FDC).

Potassium is on the label. Since 2020 (2021 for smaller companies) the US Nutrition Facts label must show potassium in milligrams (FDA). The % Daily Value is based on 4,700 mg (FDA: Daily Values), far more than a kidney limit, so read the milligrams (Reading food labels).

Hidden potassium

Not all potassium is absorbed the same way (KDIGO 2024, Figure 33, from Picard 2021):

Source How much your body absorbs
Fresh fruit, vegetables, beans and grains about 50–60 %
Meat, fish and dairy about 70–90 %
Potassium additives (potassium chloride, potassium lactate and other potassium salts) about 90 %

KDIGO notes that processed foods, meats, dairy, juices and salt substitutes are "actually higher in absorbable potassium than many plant-based fresh foods". It advises limiting foods rich in bioavailable potassium, such as processed foods, when potassium runs high (KDIGO 2024, practice point 3.11.5.2). Where hidden potassium turns up:

  • Salt substitutes such as NoSalt and Nu-Salt (potassium chloride) and Lite Salt (a mix of salt and potassium chloride) (NoSalt and Nu-Salt labels; Morton Lite Salt label; Sodium).
  • "Reduced-sodium" soups, broths, sauces and deli meats, which often swap salt for potassium chloride.
  • "Enhanced" fresh meat and poultry, injected with a salt and phosphate solution. In one study, 5 of 25 enhanced products had at least 692 mg of potassium per 100 g, against under 387 mg in plain meat, and 8 of the 25 did not list the additives (Sherman and Mehta 2009).

What to do

  • Ask what your last blood potassium was and whether you need a limit at all.
  • If you do: keep fruit and vegetables to ½-cup portions and pick from the low list (Food lists).
  • Swap the few very high foods (table below) before cutting healthy fruit and vegetables.
  • Read ingredient lists for "potassium chloride" and other potassium salts.
  • Buy plain meat and poultry, not "enhanced" or "contains up to X % of a solution".
  • Never use salt substitutes such as NoSalt, Nu-Salt or Lite Salt unless your team says so.
  • Drain the juice from canned fruit and vegetables; it holds potassium (NKF).
  • Leach potatoes and other root vegetables if you eat them (Potassium leaching).
  • Keep your bowels moving and your glucose in range: constipation and high glucose raise potassium.
  • Never delay treating a low because of potassium. Glucose tablets have none, and a 4-oz glass of orange juice (about 250 mg) still fits a day's budget (Treating a low).

Examples: swaps that save the most

Instead of Potassium Try Potassium
Banana, 1 medium 422 mg Blueberries, ½ cup 57 mg
Baked potato with skin, 1 medium 926 mg White rice, ½ cup 28 mg
Orange juice, 1 cup 496 mg Apple juice, ½ cup 125 mg
Tomato sauce, ½ cup 365 mg Olive oil and garlic on pasta about 0–25 mg
Spinach, cooked, ½ cup 419 mg Cabbage, cooked, ½ cup / green beans, ½ cup 147 / 92 mg
Milk, 2 % fat, 1 cup 342 mg Almond milk, unsweetened, 1 cup / rice milk, 1 cup 176 / 65 mg
Avocado, ¼ 242 mg Cucumber, ½ cup 76 mg
Potato chips, 1 oz 335 mg Air-popped popcorn, 3 cups 79 mg

Values from USDA FoodData Central (SR Legacy), as in the app's food list (FDC). Rice milk is low in potassium but not in phosphorus, so check both if you limit phosphorus.

Example: one day, two ways

The same four meals, with the high-potassium foods swapped (FDC):

Meal Higher-potassium version K mg Swapped version K mg
Breakfast 1 cup oatmeal, 1 medium banana, 1 cup 2 % milk 928 1 cup Cream of Wheat, ¾ cup blueberries, 1 cup unsweetened almond milk, 1 slice toast 338
Lunch 6-inch deli sub, 1 oz potato chips 884 Sandwich with 2 oz turkey you roast yourself, lettuce and mayonnaise, ½ cup grapes 413
Dinner 3 oz chicken, baked potato with skin, ½ cup cooked spinach 1,565 3 oz chicken, ¾ cup white rice, ½ cup green beans 353
Snack 1 cup cantaloupe 427 3 cups air-popped popcorn 79
Day about 3,800 about 1,200

The swapped day saves about 2,600 mg, which leaves room for fruit and vegetables you enjoy. The carbohydrate changes too (about 177 g against 161 g), so count each meal as usual (Carb counting).

In the app

Every food shows a potassium warning per serving, and your day shows how close you are to your potassium target. If you add a potassium result under Labs, the app adjusts its review ceiling: a normal result relaxes it one step (unless you have had high potassium before), a high result tightens it, and a low result removes it (design note 05). See Targets and warnings and Logging food.

Ask your care team

  1. What was my last potassium result, and do I need a limit? What number?
  2. Which of my medicines raise potassium, and when is my next blood test after a change?
  3. Can I eat more fruit and vegetables while my potassium is normal?
  4. Should I take a potassium binder, and how does it fit with my meals?
  5. What should I do if my potassium comes back high but I feel fine?

Get help now if…

Call 911 (or your local emergency number)

Your lab potassium is 6.5 mmol/L or more (KDIGO 2024, Table 28), or you have fainting, a very slow or irregular pulse, chest pain or sudden severe weakness and your potassium has been high (MedlinePlus).

Call your care team today

A result of 6.0–6.4 mmol/L: if you feel unwell, go to hospital now to be checked and treated; if you feel well, call your team today for a repeat test within 24 hours (KDIGO 2024, Table 28). Also call if vomiting or diarrhea stops you eating or drinking. Full list: Get help now.

Sources

Not yet reviewed by a clinician. Facts and sources last checked 2026-10-06.