What Nutrients Are Potatoes Deficient In?

December 21, 2025 •

2 min read

Despite being a staple food for centuries, a medium white potato contains virtually no Vitamin A. This popular vegetable, when eaten as the sole food source, lacks several key vitamins and minerals necessary for long-term health.

Quick Summary

Potatoes, while rich in vitamin C and potassium, have notable deficiencies in vitamins A, E, K, and B12, as well as calcium, selenium, and omega-3 fatty acids.

Key Points

Fat-Soluble Vitamin Shortfall: White potatoes are significantly deficient in vitamins A, E, and K, which are vital for vision, immune health, and blood clotting.
No Vitamin B12: As with most plant foods, potatoes contain no Vitamin B12, a nutrient essential for nerve and red blood cell health, making supplementation necessary for vegans.
Low in Essential Fatty Acids: Potatoes lack omega-3 fatty acids, which are crucial for brain and heart health and must be obtained from other dietary sources.
Mineral Gaps: They provide insufficient amounts of calcium and selenium, requiring diverse food sources to meet daily needs for these minerals.
High-Quality but Low Quantity Protein: The protein in potatoes is complete, containing all essential amino acids, but the overall amount is very low, making it an insufficient sole protein source.
Preparation Matters: Boiling potatoes can cause water-soluble nutrients like Vitamin C and potassium to leach out, while baking with the skin on preserves more vitamins.
Not a Complete Diet: While nutritious in moderation, relying on potatoes alone for sustenance is not viable long-term and can lead to severe malnutrition.

Key Nutrient Deficiencies in Potatoes

While potatoes offer a solid foundation of carbohydrates and are a good source of vitamin C and potassium, relying on them exclusively would lead to several nutrient deficiencies over time. To achieve a balanced diet, it is crucial to supplement potatoes with other foods to provide a wider spectrum of vitamins, minerals, and macronutrients.

Vitamin Deficiencies

White potatoes are notably low or entirely lacking in several fat-soluble and water-soluble vitamins. They offer less than 1% of the daily value for Vitamin A, essential for vision and immune function, unlike sweet potatoes which are packed with it. Potatoes are also deficient in Vitamin E, an antioxidant, and Vitamin K, important for blood clotting and bone health. A potato-focused plant-based diet would also lack Vitamin B12, primarily found in animal products.

Mineral and Fat Deficiencies

Potatoes are insufficient in critical minerals like calcium, vital for bone health. While containing potassium, they can be low in calcium. A long-term potato-only diet would also lead to a selenium deficiency. Additionally, potatoes contain minimal fat and lack essential omega-3 fatty acids, crucial for brain and heart function.

Protein Quality vs. Quantity

Potatoes contain all nine essential amino acids, making their protein high quality. However, the quantity is very low, providing only a few grams per medium potato. Consuming enough potatoes for sufficient protein is impractical due to the caloric load.

Nutrient Comparison: White Potatoes vs. Sweet Potatoes

Comparing a medium-sized, baked white potato with a medium sweet potato highlights their differing nutritional profiles. Baking with the skin on preserves most vitamins compared to boiling.


Nutrient	White Potato (approx. 150g)	Sweet Potato (approx. 150g)
Calories	~130-160 kcal	~130-160 kcal
Protein	~3g	~2g
Carbohydrates	~30-37g	~23-24g
Dietary Fiber	~3-4g	~4g
Vitamin A	<1% Daily Value	>100% Daily Value
Vitamin C	Good source	Good source
Potassium	Excellent source	Good source
Calcium	Low	Moderate

How to Create a Balanced Meal with Potatoes

Incorporating potatoes into diverse meals is key for complete nutrition.

Vitamin A: Combine with colorful vegetables or sweet potatoes.
Vitamins E and K: Add healthy fats, nuts, seeds, or leafy greens.
Calcium: Pair with dairy, fortified plant-based milk, or kale.
Protein: Add lean protein like chicken, fish, lentils, or beans.
Omega-3s: Use olive oil or include salmon or walnuts.

Conclusion

Potatoes are nutritious but not a complete food. A diet solely of potatoes leads to deficiencies in vitamins A, E, K, B12, calcium, selenium, and omega-3s. Enjoy potatoes as part of a varied diet for optimal health.

For more nutritional details, see the University of California - Davis Health blog.

Frequently Asked Questions

Yes, white potatoes contain virtually no Vitamin A. Sweet potatoes, however, are an excellent source of this nutrient, which is essential for vision and immune function.

No, while the protein in potatoes is considered 'complete' because it contains all essential amino acids, the overall amount is very low. You would need to eat an impractical number of potatoes to meet your daily protein needs.

No, potatoes do not contain Vitamin B12. This vitamin is primarily found in animal products, and plant-based diets typically require supplementation or fortified foods to obtain sufficient amounts.

A diet of only potatoes would lead to malnutrition over time, as it lacks several key vitamins (A, E, K, B12), minerals (calcium, selenium), and essential fatty acids. While some individuals have done it for short periods, it is not sustainable or recommended by health professionals.

To balance a potato-based meal, combine it with foods that provide the missing nutrients. Add lean protein like chicken or legumes, leafy greens for Vitamin K and calcium, and healthy fats like olive oil for omega-3s and Vitamin E.

Baking or steaming potatoes with their skin on is the best method to preserve their nutrient content. Water-soluble vitamins like Vitamin C and potassium can be lost if potatoes are boiled for too long.

Potatoes are a good source of some minerals like potassium, magnesium, and phosphorus, but they are notably low in others like calcium and selenium. Different minerals are concentrated in the skin.