How Much Calcium Is In Potatoes? | Mineral Facts

Potatoes get plenty of attention for their potassium content — one medium spud delivers around 15% of your daily needs. That reputation sometimes makes people wonder whether potatoes are a solid source of other minerals, including calcium.

The honest answer is that potatoes are not a significant calcium source. A medium skin-on russet provides about 22 mg of calcium, roughly 2% of the daily target. Here is what that number means alongside your overall calcium needs.

How Much Calcium a Single Potato Actually Delivers

The exact calcium count depends on the potato size and variety, but the numbers stay consistently low across the board. A small raw russet potato (about 1-3/4 to 2-1/4 inches across) contains roughly 22 mg of calcium when you leave the skin on.

Potato Skin and Calcium

The potato flesh itself averages around 5 mg of calcium per 100 grams. The skin does hold more minerals than the flesh, but calcium is not one of them in significant amounts. The skin is a better source of fiber, potassium, and magnesium.

Compare that to a medium potato’s 620 mg of potassium or 39 mg of magnesium. Calcium simply isn’t a mineral potatoes accumulate in meaningful amounts.

Why People Assume Potatoes Are a Calcium Source

Several nutritional myths contribute to the idea that potatoes deliver calcium. Here is where the confusion usually starts.

• Potassium vs. calcium confusion: Potatoes are a high-potassium food, and many people lump all minerals together. A medium potato provides about 18% of the daily value for potassium, but only 2% for calcium.
• The skin-as-nutrient-dense idea: Potato skin does contain more minerals than the flesh, but that doesn’t mean it is rich in calcium. The skin holds fiber and potassium far more than it does calcium.
• Dairy side dishes create an illusion: Baked potatoes loaded with butter, sour cream, or cheese feel like a calcium-rich meal. But the potato itself contributes very little to the total calcium count.
• White vegetable bias: People tend to assume colorful vegetables have more nutrients, but white vegetables like potatoes still get credit for being a healthy option. That health halo sometimes overstates their mineral profile.

The reality is that potatoes excel at providing potassium, vitamin C, and vitamin B6, but calcium is not part of their strong suit.

Why Bioavailability Matters in Potato Calcium

Even the modest calcium in a potato may not be fully available to your body. Potatoes contain oxalates, naturally occurring compounds that can bind to calcium in the digestive tract and limit absorption.

The NCBI table on oxalate-rich foods with low calcium notes that rhubarb and sweet potatoes have oxalates but not enough calcium for it to matter much. Potatoes follow a similar pattern.

WebMD notes a medium baked potato may contain around 97 mg of oxalates, with a good portion concentrated in the skin. That oxalate load may keep the potato’s own calcium from being fully usable.

Food	Calcium (mg)	Oxalate Content
Medium baked potato (skin on)	~22 mg	~97 mg (moderate)
1 cup spinach (cooked)	240 mg	Very high
1/2 cup rhubarb (cooked)	175 mg	Very high
1 cup whole milk	300 mg	Negligible
4 oz canned salmon (with bones)	240 mg	Negligible
1 cup cooked kale	90 mg	Low

The takeaway here is that the calcium-to-oxalate ratio matters. Foods with low calcium relative to their oxalate content may not contribute meaningful absorbable calcium.

How to Get the Most Out of Potato Calcium

If you enjoy potatoes and want to support your calcium intake, a few simple strategies can help your body use what little calcium is there.

1. Pair potatoes with a calcium-rich food: Some dietitians suggest eating a baked potato with a dairy or non-dairy calcium source. The calcium from milk, cheese, or fortified plant milk can bind to excess oxalate in the digestive tract.
2. Don’t rely on potatoes for calcium: A medium potato gives only 2% of your daily calcium needs. Get the bulk of your calcium from dairy, fortified plant milks, leafy greens, or canned fish with bones.
3. Vary your vegetable intake: Rotate potatoes with low-oxalate vegetables like broccoli, zucchini, or bell peppers to keep oxalate load moderate and maintain mineral diversity.
4. Consider cooking methods: Boiling potatoes can reduce oxalate content slightly compared to baking, since some oxalates leach into the water. Discarding the cooking water may help.

These steps don’t turn potatoes into a calcium powerhouse, but they support overall mineral balance.

How Potato Calcium Compares to Real Sources

To put the 22 mg of calcium in a medium potato into perspective, comparing it to foods that actually move the needle on your daily intake is helpful. The recommended daily value for calcium is around 1,000 mg for most adults.

An NIH review of calcium absorption research found that the food matrix matters a great deal — absorption can range from less than 10% to over 50%. Dairy products tested in premenopausal women showed an average absorption rate of 31.2%, making them efficient sources compared to most plant foods.

A medium Idaho potato provides about 620 mg of potassium and 22 mg of calcium. That mineral split means potatoes work well as a potassium vehicle, but they are not a calcium vehicle.

Food	Serving Size	Calcium (mg)
Russet potato (skin on)	1 medium	~22 mg
Whole milk	1 cup	300 mg
Plain yogurt	1 cup	300-450 mg
Cooked kale	1 cup	90 mg
Canned sardines (with bones)	3 oz	320 mg

The contrast is clear. One cup of milk provides roughly 13 times the calcium of a medium potato, and the calcium from milk is highly absorbable.

The Bottom Line

Potatoes contain calcium, but the amount is modest enough that they shouldn’t be counted as a calcium source. A medium russet provides about 22 mg — roughly 2% of the daily target — and the oxalates in the potato may reduce how much of that calcium is actually absorbed.

For bone health, kidney stone prevention, or dietary planning, focus on dairy, fortified plant milks, kale, or canned fish with bones for your calcium. If you have kidney stone concerns or dietary restrictions, a registered dietitian can help you balance your specific oxalate tolerance and calcium needs without eliminating foods you enjoy.