How many carbs are in 1 cup of homemade mashed potatoes?

Mashed potatoes are a classic comfort food that can be a tasty side dish or meal on their own. While delicious, mashed potatoes are also high in carbohydrates. Knowing how many carbs are in mashed potatoes can help you make informed choices about portion sizes and overall nutrition.

Quick Answer

One cup of homemade mashed potatoes contains approximately 30-35 grams of net carbs.

What Are the Macronutrients in Mashed Potatoes?

Mashed potatoes are made by boiling and then mashing potatoes. The main macronutrients in one cup of mashed potatoes are:

  • Carbohydrates: 35-40 grams
  • Protein: 3-4 grams
  • Fat: 0.5 grams

As you can see, carbohydrates make up the majority of calories in mashed potatoes. The exact carb count can vary slightly depending on the type and size of potatoes used.


The carbohydrates in mashed potatoes come mostly from starch. Potatoes are almost entirely made up of starch, with a small amount of sugar. Starch is a complex carb that the body breaks down into glucose.

One medium baked potato with the skin on contains about 30-35 grams of total carbohydrates. When boiled and mashed, the amount of carbs remains similar at around 35-40 grams per cup.


Potatoes also contain fiber, which is a type of carbohydrate that isn’t digested. The skin of the potatoes contains the majority of the fiber.

One medium baked potato with skin provides 3-4 grams of fiber. When the potatoes are peeled and mashed, the fiber content decreases to around 1-2 grams per cup.

Net Carbs

Net carbs refer to the number of digestible carbs that impact blood sugar levels. You calculate net carbs by subtracting the grams of fiber from the total carbohydrates.

Since one cup of mashed potatoes made from peeled potatoes contains about 35-40 grams of total carbs and 1-2 grams of fiber, the net carb amount comes to around 30-35 grams.

Factors That Affect Carb Count

Several factors can alter the exact carbohydrate content in one cup of homemade mashed potatoes:

Type of Potato

The most common types of potatoes used for mashing include:

  • Russet – A starchy potato that makes fluffier mashed potatoes.
  • Yukon Gold – A waxy potato that makes creamier mashed potatoes.
  • Red potatoes – Lower in starch and calories compared to Russets.

Russet potatoes contain slightly more carbs than Yukon Gold or red potatoes. Using a different potato variety can alter the carb amount by a few grams per cup.

With Skin or Peeled

Leaving the potato skin on adds additional fiber, which lowers the net carbs. Peeling the potatoes before boiling increases the carb content since you lose that extra fiber.

Added Ingredients

Ingredients like butter, cream, cheese, bacon, and sour cream are often added to mashed potatoes. This can increase the calories and fat but doesn’t significantly impact the amount of carbohydrates per cup.

Cooking Method

The cooking method can also affect the nutrient composition. Mashed potatoes tend to have a similar carb count whether they are boiled, baked, or microwaved prior to mashing.

Glycemic Index

The glycemic index (GI) is a scale that ranks carbohydrate-containing foods by how much they impact blood sugar levels. Potatoes have a high GI, meaning they cause a rapid rise in blood sugar compared to other carb sources.

Boiled potatoes have a GI around 78, while mashed potatoes are slightly higher at around 85. Foods with a high GI may lead to spikes and crashes in energy levels.

Comparing Mashed Potatoes to Other Carb Sources

Here’s how the net carbs in 1 cup of mashed potatoes compare to other carb-containing foods:

Food Net Carbs
Mashed potatoes (1 cup) 30-35 grams
Pasta – cooked (1 cup) 40-50 grams
Rice – cooked (1 cup) 45-55 grams
Bread – sliced (1 slice) 12-15 grams
Oatmeal – cooked (1 cup) 20-25 grams

Mashed potatoes have a medium carb count compared to other common starch foods. Pasta and rice both contain more net carbs per cooked cup. Bread and oatmeal have fewer carbs than mashed potatoes in typical serving sizes.

Tips for Managing Carbs in Mashed Potatoes

Here are some tips for keeping mashed potatoes as part of a healthy diet:

Watch Portions

Stick to sensible portions of around 1 cup. Larger portions will substantially increase the carb intake.

Increase Fiber

Leaving the potato skins on or mixing in extra vegetables boosts fiber, which lowers net carbs. Try making mashed cauliflower potatoes by replacing half the potatoes with cauliflower.

Pair with Protein and Fat

Eating potatoes alongside meat, fish, eggs, cheese, or other proteins and fats helps slow digestion and prevents blood sugar spikes.

Choose Lower-Carb Toppings

Rather than butter, cream, or gravy, opt for heart-healthy toppings like plain Greek yogurt, olive oil, or avocado.

Reduce Portion of Other Carbs

If enjoying mashed potatoes as a side, cut back on other high-carb foods at the meal like grains or bread to keep total carbs moderate.

Cooking Low-Carb Mashed Potatoes

There are also some easy substitutes to reduce the net carbs in mashed potato recipes:


Replace about half the potatoes with cauliflower when boiling and mashing. Cauliflower is very low in carbs.

Turnips or Rutabagas

Turnips and rutabagas make delicious lower-carb additions to mashed potatoes, providing more nutrients as well.

Cheese and Sour Cream

Mix in high-protein ingredients like shredded cheese, Parmesan, and sour cream to lower the ratio of carbs to other nutrients.

Garlic and Herbs

Boost flavor with garlic, chives, dill, parsley and other fresh herbs so less butter and salt are needed.

Unsweetened Almond Milk

For a dairy-free option, use unsweetened almond milk instead of regular milk when making the mash.

Mashed Potato Nutrition Facts

Here are the full nutrition facts for a 1-cup serving of basic homemade mashed potatoes made with peeled, boiled potatoes and milk:

Nutrient Amount
Calories 220
Fat 0.5 g
Sodium 25 mg
Carbohydrates 40 g
Fiber 2 g
Sugar 3 g
Protein 4 g

Vitamins and Minerals

Mashed potatoes also provide vitamins and minerals, including:

  • Vitamin C
  • Vitamin B6
  • Potassium
  • Iron
  • Magnesium
  • Phosphorus

The exact amounts vary based on preparation methods. Leaving the skins on boosts the vitamin, mineral, and fiber content.

Health Benefits of Potatoes

Despite their high carb count, potatoes do offer some health benefits. Potatoes provide:

  • Vitamins and minerals – Especially when eaten with skin on.
  • Fiber – Most is found in the skin, which helps regulate digestion.
  • Antioxidants – Potatoes contain antioxidants like carotenoids and phenolic acids.
  • Resistant starch – Raw or cooled mashed potatoes contain resistant starch linked to digestive health.

There are also unique types like purple potatoes that contain antioxidants called anthocyanins. Potatoes, including mashed varieties, can be part of a nutritious diet in moderation.

Risks and Concerns

There are some potential downsides to potatoes worth noting:

  • High glycemic index – Can affect blood sugar control.
  • Nightshade vegetable – Potatoes are nightshades, which some people can’t tolerate.
  • Acrylamide – A potential carcinogen formed when potatoes are fried or baked at high temperatures.
  • Solanine poisoning – Green potatoes contain the toxin solanine that can cause illness if consumed in large amounts.

These risks mainly apply to potatoes that are prepared unhealthily at high temperatures. Enjoying boiled mashed potatoes in reasonable amounts is unlikely to pose risks in healthy people.

Mashed Potato Recipe Ideas

Beyond basic mashed potatoes, there are many delicious recipes to try:

Garlic Mashed Potatoes

Roast garlic cloves and mash them into potatoes along with olive oil or butter for added flavor.

Loaded Mashed Potato Bake

Top mashed potatoes with cheese, bacon, scallions, and sour cream then bake until browned and bubbly.

Mashed Potato Pancakes

Combine mashed potatoes with egg, flour, and any mix-ins to make tasty potato pancakes or latkes.

Cheddar and Green Onion

Stir in shredded cheddar cheese, sliced green onions, garlic powder, salt, and pepper for easy flavor.

Mashed Potato Bowls

Scoop mashed potatoes into bowls and top with sautéed veggies, shrimp, chicken, or beef for a hearty meal.


Mashed potatoes are a treasured comfort food, but with a significant carb load. One cup of homemade mashed potatoes made with peeled, boiled potatoes contains approximately 30-35 grams of net carbs.

The exact amount of carbs can vary based on potato type, added ingredients, and cooking method. Potatoes do provide fiber, vitamins, minerals, and antioxidants when not prepared unhealthily. Enjoy mashed potatoes in sensible portions alongside other nutritious foods to balance your diet and blood sugar level.

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