You probably learned about the pH scale in your high school chemistry class. What seemed like information you would never use back then is actually relevant when it comes to an alkaline diet plan and the alkaline vegetables list you should stick to.
To understand the alkalinity in certain foods, you must be familiar with the following pH scale:
- Acidic: 0.0 to 6.9
- Neutral: 7.0
- Alkaline (Basic): 7.1 to 14.0
The pH level throughout your body affects various bodily functions. For example, the stomach is highly acidic, which is necessary to break down and digest food. Blood, on the other hand, is slightly above neutral leaning towards alkalinity. The pH of these systems is tightly regulated and is not something to be changed.
Some people stick to alkaline fruits and vegetables for the proposed health benefits and reduced risk of diseases. Fortunately, the alkaline vegetables list is extensive, but the evidence is mixed. The pH of food does not and should not change the pH of the body, though it may alter the pH of urine. Whether the alkalinity of vegetables is beneficial is uncertain, though it is certain that vegetables are proven sources of beneficial nutrients.
Low- Versus High-Alkaline Veggies
Alkaline fruits and vegetables naturally have a higher pH value. However, some are more alkaline than others. There are low alkaline vegetables and high alkaline vegetables. Most vegetables are at least slightly alkaline.
To determine whether veggies are acidic, neutral or a varying degree of alkaline, they must be tested for their potential renal acid load. This is also known as a PRAL score, and it indicates the acidity of a food.
In a July 1995 study published in the Journal of the American Dietetic Association, it was discovered that PRAL scores affect the pH level of urine. This study was the first of its kind, and explains why people who follow the alkaline diet plan test their urine on pH strips.
To make it onto the high alkaline vegetables list, a veggie must have a very low PRAL score. These scores go into the negative, which some vegetables — such as spinach — have a score as low as negative 16.
Read more: What Is an Alkaline Diet?
Are Alkaline Veggies Beneficial?
Vegetables are high in vitamins, minerals and antioxidants, and they are linked to various health benefits. However, the alkaline diet plan proposes that high alkaline vegetables are superior to acidic or low alkaline veggies.
The alkaline trend dates back to the 1800s, and it was believed that certain foods leave behind "ash" or metabolic waste. According to this theory, high alkaline foods should remove that waste while also encouraging overall health. Today, followers of the alkaline diet hope to protect against diabetes, heart disease, cancer and other diseases.
There is very little scientific evidence that supports these claims. The American Institute for Cancer Research acknowledges that acidic foods can promote cancer in an isolated lab setting, but this claim is unsupported in the human body. They do not recommend you consume only alkaline foods but rather incorporate a variety of vegetables, fruits, legumes and grains.
The health benefits of high alkaline vegetables may be due to the nutritional content instead of the pH value. An October 2012 study published in the Journal of Environmental and Public Health concluded that the alkaline diet may improve bone health and improve the conditions of chronic diseases due to increased fruit and vegetable intake.
A more alkaline diet may also help patients with kidney disease due to greater vegetable consumption, according to a May 2017 study published in the Journal of Renal Nutrition.
Cruciferous Vegetables Are Alkaline
The majority of veggies, including cruciferous vegetables, are alkaline. Some cruciferous veggies are slightly alkaline, such as cauliflower, brussels sprouts and cabbage. Broccoli and radishes are higher on the alkalinity scale.
There is speculation that these high alkaline veggies help reduce the formation of kidney stones and address calcium deficiency. Increasing your intake of broccoli may help with both of these health concerns.
Read more: Acid vs. Alkaline in the Body
Alkaline Leafy Greens
Dark leafy greens are at the top of the alkaline vegetables list. Spinach is one of the most alkaline foods, while other leafy greens follow closely behind: kale, arugula, collard greens, mustard greens, beet greens and watercress are a few.
Claims of cancer prevention contribute to the popularity of the high alkaline diet plan, and leafy greens are at the forefront of these proposed benefits. Leafy vegetables are high in antioxidants called carotenoids, especially lutein and zeaxanthin.
A February 2014 study published in Nutrients found that these antioxidants can reduce the risk of certain cancers, including lung, prostate and throat. However, more research is needed.
Read more: List of Natural Alkaline Drinks
High-Alkaline Root Vegetables
Root vegetables like onions and potatoes are a staple in American diets. These roots along with chicory, beets and parsnips are also high alkaline.
One trait that high alkaline root vegetables exhibit is their polyphenol content. Polyphenols are phytochemicals known for exhibiting antioxidant, anti-inflammatory and anti-cancer properties. In a September 2016 study published in Nutrients, researchers found that dietary polyphenols are linked to a reduced risk of breast cancer. They recommend five servings of fruits and vegetables, which are naturally alkaline, per day as part of a healthy eating pattern similar to the Mediterranean diet.
A November 2010 study was published in the European Journal of Clinical Nutrition identified the 100 richest sources of dietary polyphenols. Sixteen of them were vegetables, and five of those are alkaline root vegetables: chicory, onions, shallots, potatoes and carrots.
Read more: Is Milk Alkaline or Acidic?
Other High-Alkaline Vegetables
The remaining high alkaline veggies include celery, cucumber, eggplant, mushrooms and peppers. Due to their high alkalinity, some of these vegetables may be associated with the prevention of muscle loss.
A June 2013 study published in Osteoporosis International found a significant positive association between an alkaline diet plan and muscle mass index. They noted that consuming vegetables high in potassium and magnesium is a contributing factor.
High alkaline veggies like celery, cucumbers and mushrooms are naturally high in potassium, and leafy greens provide magnesium. According to the USDA, mushrooms are the eighth highest source of potassium. USDA data also yields spinach as the number one source of magnesium.
Read more: Alkaline Foods for Breakfast
Eat Alkaline Fruits and Vegetables
It is unclear if alkaline fruits and vegetables are beneficial strictly because of their pH value. However, their health benefits have been confirmed due to other factors, such as vitamins, minerals, antioxidants and polyphenols.
Many high alkaline veggies have proven health benefits — such as the prevention of kidney stones, some cancers and muscle loss — but these benefits are not attributed strictly to the alkalinity scores.
More research is needed to confirm the relationship between alkalinity and health, but scientific evidence points to consuming more veggies, regardless of pH value, as part of a healthy eating pattern.
- Journal of the American Dietetic Association: “Potential Renal Acid Load of Foods and Its Influence on Urine pH”
- American Institute for Cancer Research: “Alkaline Diets”
- Journal of Environmental and Public Health: “The Alkaline Diet: Is There Evidence That an Alkaline pH Diet Benefits Health?”
- Journal of Renal Nutrition: “Reducing the Dietary Acid Load: How a More Alkaline Diet Benefits Patients With Chronic Kidney Disease.”
- Mayo Clinic: “Boost Your Calcium Levels Without Dairy? Yes You Can!”
- Nutrients: “Potential Role of Carotenoids as Antioxidants in Human Health and Disease”
- European Journal of Clinical Nutrition: “Identification of the 100 Richest Dietary Sources of Polyphenols: An Application of the Phenol-Explorer Database”
- Nutrients: “Reducing Breast Cancer Recurrence: The Role of Dietary Polyphenolics”
- Osteoporosis International: “A Higher Alkaline Dietary Load is Associated With Greater Indexes of Skeletal Muscle Mass in Women”
- MyFoodData: “Top 10 Foods Highest in Potassium”
- MyFoodData: “Top 10 Foods Highest in Magnesium”