Are Boiled Potatoes Acidic or Alkaline?

October 23, 2025 •

4 min read

While the raw pH of a potato is mildly acidic, its effect on the body is largely alkalizing. This surprising distinction is important for those managing acid reflux or following an alkaline diet, making a simple boiled potato a beneficial addition to many meal plans.

Quick Summary

Despite a mildly acidic raw pH, potatoes are considered an alkaline-forming food based on their low potential renal acid load (PRAL). Cooking methods like boiling do not significantly alter this alkalizing effect on the body's chemistry.

Key Points

PRAL vs. pH: Raw potatoes are mildly acidic (pH 5.4-5.9), but are highly alkalizing in the body due to their negative PRAL score.
Alkalizing Effect: Potatoes are rich in potassium, which is an important mineral that contributes to their alkalizing effect after digestion.
Cooking Method is Key: Boiling does not compromise the potato's alkalizing properties, but high-fat preparations like frying can trigger acid reflux.
Good for Digestion: Plain boiled potatoes are low in fat and easy to digest, making them a safe choice for those with sensitive stomachs or acid reflux.
Part of a Healthy Diet: Eating more fruits and vegetables, including potatoes, is a key component of a healthy, balanced diet, regardless of strict alkaline diet claims.
Rich in Nutrients: Potatoes provide valuable vitamins and minerals, and cooking methods like boiling can retain or even enhance some of their nutritional value.

Understanding the Difference: pH vs. PRAL

To determine if boiled potatoes are acidic or alkaline, we must first understand the two different ways to measure this property: the food's inherent pH and its effect on the body after digestion, known as the Potential Renal Acid Load (PRAL).

The Food's pH: A Raw Measurement

The pH scale measures how acidic or alkaline a substance is, ranging from 0 (most acidic) to 14 (most alkaline), with 7 being neutral. In its raw state, a potato has a pH of approximately 5.4 to 5.9, which makes it mildly acidic. This is due to the presence of natural organic acids like citric, malic, and oxalic acids. This inherent acidity is a minor factor in cooking and nutrition, and boiling does not substantially change this fundamental property.

The PRAL: The Body's Reaction

For dietary purposes, the PRAL score is far more relevant. It measures the acid or alkaline load a food places on the kidneys after it is metabolized. The body tightly regulates blood pH within a very narrow, slightly alkaline range (around 7.35–7.45). To do this, the kidneys filter out excess acid or base load. A negative PRAL score indicates that a food has an alkalizing effect on the body, while a positive score indicates an acidifying effect. With a PRAL value of around -6, potatoes are firmly considered an alkaline-forming food. This is because they are rich in alkalizing minerals such as potassium, which helps the body neutralize metabolic acids.

The Effect of Cooking on Potato Alkalinity

Boiling potatoes does not diminish their alkalizing effect and, in some cases, can even enhance the availability of certain nutrients. Contrary to the misconception that boiling leaches out all beneficial properties, studies have shown that antioxidant capacity and other nutrients are well-retained or even increased in cooked potatoes. While some water-soluble vitamins might be lost, the overall alkalizing effect remains consistent.

Comparing Boiled and Other Potato Preparations

Cooking method is key when considering digestive health, especially for those with acid reflux. While plain boiled or baked potatoes are excellent choices, some preparations can negate the benefits.


Comparison of Potato Preparation and Digestive Impact	Cooking Method	Fat Content	PRAL Effect	Impact on Digestion (Acid Reflux)
Boiled	Very Low	Alkalizing	Excellent; easy to digest.
Baked	Very Low	Alkalizing	Excellent; low in fat.
Fried (French Fries)	High	Still Alkalizing	Poor; high fat can trigger reflux.
With Butter/Sour Cream	High	Still Alkalizing	Poor; fatty toppings can worsen symptoms.

Why Alkaline Foods are Important for Health

The concept of an alkaline diet is based on the idea of reducing the body's acid load, which proponents claim can improve health outcomes. While science does not support that food can significantly alter the body's blood pH, there is ample evidence that eating more fruits and vegetables is beneficial.

Bone Health: Consuming more alkalizing fruits and vegetables, like potatoes, which are rich in potassium, may help protect against decreased bone strength and muscle wasting as we age.
Cardiovascular Health: An increased intake of plant-based, alkalizing foods may improve cardiovascular health and help protect against issues like hypertension.
General Wellbeing: An emphasis on fresh, unprocessed, and plant-based foods, which is central to an alkaline-focused diet, has been shown to provide other health benefits, including reducing inflammation and improving overall nutritional intake.

How to Incorporate Boiled Potatoes into an Alkaline-Focused Diet

Adding boiled potatoes to a health-conscious diet is simple and effective. Here are a few ways to include them:

Simple Side Dish: Serve plain boiled potatoes as a nutritious side to a lean protein and green vegetables. Season with a sprinkle of sea salt and herbs like parsley or dill.
Potato Salad (Healthy Style): Create a healthy potato salad by mixing cooled, boiled potato chunks with a yogurt-based dressing (non-dairy options are available) and plenty of vegetables like celery, bell peppers, and fresh herbs.
Creamy Potato Soup: For a soothing meal, blend boiled potatoes with vegetable broth and a splash of non-dairy milk or cream to create a rich and creamy, yet alkaline-friendly, soup. Avoid heavy cream and excess butter.
Mashed Potatoes (Dairy-Free): Prepare mashed potatoes using non-dairy milk or a little olive oil for flavor, keeping the dish low in fat and still highly alkalizing.

Conclusion: The Balanced View on Boiled Potatoes

Ultimately, when asking are boiled potatoes acidic or alkaline?, the answer depends on the context. Based on their raw pH, they are mildly acidic. However, in terms of their effect on the body's metabolism, they are decidedly alkalizing. The key takeaway is to focus on the nutritional impact rather than just the raw chemical properties. A plain boiled potato is a low-fat, easy-to-digest food that can contribute positively to overall health, especially for those focusing on an alkaline-rich diet or seeking relief from acid reflux. Avoiding high-fat cooking methods and toppings is the most important factor for maximizing these digestive benefits. Incorporating boiled potatoes is a simple, whole-food step towards a balanced and nutritious diet, regardless of how you interpret their acid-alkaline profile.

Can you eat potatoes on an alkaline diet?

Yes, potatoes are considered a foundational food in an alkaline-focused diet because of their strong alkalizing effect on the body.

The Effect of High-Fat Preparations

It is important to remember that adding high-fat ingredients like excess butter, sour cream, or frying the potatoes can trigger acid reflux and other digestive issues, regardless of the potato's alkalizing properties. The healthy aspects of the potato are best preserved when cooked simply through boiling or baking.

Authoritative Link

For further information on the potential renal acid load and its implications for kidney health, you can consult this article: Potential Renal Acid Load and Its Impact on Kidney Disease.

Frequently Asked Questions

Boiling does not significantly change the potato's inherent pH. However, in terms of its effect on your body, the potato remains a strongly alkalizing food regardless of whether it is boiled, baked, or microwaved.

Yes, plain boiled potatoes are considered an excellent food for acid reflux sufferers because they are low in fat and easy to digest. High-fat cooking methods, however, should be avoided.

Potatoes have a negative Potential Renal Acid Load (PRAL) score, typically around -6, which indicates they have a strong alkalizing effect on the body after digestion.

The PRAL score is more relevant for dietary purposes because it measures a food's effect on your body's overall acid-base balance, rather than just its raw acidity. Your body tightly regulates its internal pH, and PRAL reflects how food impacts that metabolic process.

There is no scientific evidence that a strict alkaline diet can cure diseases. However, the diet's emphasis on consuming more nutrient-dense fruits and vegetables is widely recognized as a healthy eating pattern that can help reduce inflammation and lower the risk of chronic diseases.

Examples of other alkaline-forming foods include most vegetables (e.g., broccoli, spinach), fruits (e.g., bananas, avocados), nuts, and legumes.

Yes, different potato cultivars can have slightly different pH levels, but they generally all fall into the mildly acidic range when raw. For example, sweet potatoes are also mildly acidic but have an alkalizing effect on the body.