Kidney diet · Potassium and phosphorus
If your care team has you watching both minerals, the tricky part is that they do not line up: some foods low in potassium are high in phosphorus, and the other way round. Here are the foods that keep both down, the ones that fool you, and the numbers to tell them apart.
By the MedMenu Editorial Team · Published July 20, 2026
Egg whites lead the list; around them, refined grains, berries and light vegetables keep both minerals low.
Milligrams per typical portion. K = potassium, P = phosphorus.
As kidney function declines, the kidneys clear both minerals less well. High potassium affects the heart; high phosphorus pulls calcium from the bones and hardens blood vessels over time. Many people in later-stage CKD are asked to keep an eye on both. The problem is that the low-potassium list and the low-phosphorus list are not the same list, so a food that solves one can quietly worsen the other.
| Food | Portion | Potassium | Phosphorus |
|---|---|---|---|
| Egg white | 1 large | 54 mg | 5 mg |
| White rice | 1/2 cup | 28 mg | 34 mg |
| White bread | 1 slice | 32 mg | 24 mg |
| Corn flakes | 1 cup | 30 mg | 9 mg |
| Blueberries | 1/2 cup | 57 mg | 9 mg |
| Cauliflower | 1/2 cup | 88 mg | 20 mg |
| Green beans | 1/2 cup | 99 mg | 20 mg |
| Cucumber | 1/2 cup | 76 mg | 12 mg |
These are the traps. Each is genuinely low in potassium, which is why they slip through, but each carries real phosphorus.
| Food | Portion | Potassium | Phosphorus |
|---|---|---|---|
| Cheddar cheese | 1 oz | 21 mg | 127 mg |
| Whole egg | 1 large | 63 mg | 86 mg |
| Almonds | 1 oz | 205 mg | 135 mg |
| Oatmeal | 1/2 cup | 82 mg | 90 mg |
The worst trap is the one with a small number: cola and processed foods. Dark colas and many packaged foods carry added phosphate, which the body absorbs almost completely, unlike the phosphorus in whole foods. A can of cola looks modest on paper, but its phosphate is the kind that counts most. Read ingredient lists for anything with "phos" in the name.
A whole egg has about 86 mg phosphorus, almost all of it in the yolk, and about 63 mg potassium. An egg white has about 5 mg phosphorus and 54 mg potassium. So when you are limiting both minerals, egg whites, or an omelet made with one yolk and two whites, give you the protein without the phosphorus load.
Several foods that are low in both minerals, white rice, white bread and corn flakes, are high on the glycemic index, so on their own they raise blood sugar. This is where egg white earns its place: it is low in potassium, low in phosphorus, and has no carbohydrate, so it anchors a plate and slows the rise from the grains around it. An egg-white scramble with a slice of toast covers all three concerns at once.
Potassium and phosphorus values are from USDA FoodData Central (Standard Reference legacy), for the portions shown. Whole-food phosphorus is absorbed less completely than the added phosphate in processed foods, so ingredient lists matter as much as the milligrams. For scale, kidney diets often work around 2,000 mg potassium and 1,000 mg phosphorus a day as common references, so the portions above leave room. Neither mineral has a single limit that fits everyone; how much you limit is set from your blood test results, which your care team tracks.
Sources
MedMenu is an information tool, not medical advice, and does not diagnose, treat, or manage any condition. Your nephrologist and renal dietitian set your personal targets from your labs and stage. Published July 20, 2026 · Last updated July 20, 2026.
This is a comprehensive website! Recipes look great and represent a variety of cuisines. You have emphasized the appropriate nutrients. Guidance tips are helpful. Science tab provides evidence-based references and are appropriate for the diseases addressed. Links to Drugs.com, WebMD & Medline are nice. As a registered dietitian, I feel comfortable recommending MedMenu.
Susan G. Rodder, MS, RDN, LD
Registered Dietitian
MedMenu offers all the data you need to plan meals based on specific dietary needs. There are lot of great recipes from a variety of cuisines to choose from, or you can test your own recipe to see how well it fits into your dietary guidelines.
Valerie B.
MedMenu user
Diabetically Speaking with SmartMove360
Egg whites, white rice, pasta and bread, corn flakes, berries, and vegetables like cauliflower, green beans and cucumber. Egg white is the standout, at about 54 mg potassium and just 5 mg phosphorus.
Cheese, cola, egg yolks, nuts and oats. Cheddar is very low in potassium but high in phosphorus, and dark cola adds phosphate that is nearly fully absorbed. Easy to miss if you only watch potassium.
In small amounts. Cheese is low in potassium but high in phosphorus and sodium, so a light sprinkle works better than a thick slice. Cream cheese is lower in phosphorus than hard cheese.
Rather not count?
A printable week with potassium, phosphorus and sodium worked out for every meal, so both minerals stay in range without the math.
See the meal plan →