Which food has a high pH level?

December 21, 2025 •

2 min read

While most foods are naturally acidic, some have a pH value greater than 7, which makes them alkaline. Understanding which food has a high pH level is particularly useful for those interested in the alkaline diet or managing conditions like acid reflux.

Quick Summary

A high pH food, or alkaline food, includes many fruits, vegetables, nuts, and legumes. The body's metabolic response, not just the food's raw pH, determines its alkalizing effect.

Key Points

High pH Foods Explained: While few natural foods have a pH over 7, the term often refers to 'alkaline-forming' foods like many fruits and vegetables.
Top Alkalizing Foods: Excellent sources include spinach, kale, broccoli, cucumbers, avocados, and watermelon.
Citrus Is Alkalizing: Surprisingly, acidic fruits like lemons and limes have an alkalizing effect on the body after digestion, not an acid-forming one.
Health Benefits: A diet rich in alkalizing plant-based foods can improve digestion, reduce inflammation, and provide antioxidants, though it doesn't alter blood pH.
Food Safety Importance: A food's pH level is critical for safe preservation, especially canning, as it dictates the required processing method to prevent botulism.

The Science of pH and Food

The pH scale measures acidity or alkalinity, with 7 being neutral. Below 7 is acidic, and above 7 is alkaline. While many foods are acidic, their impact on the body's pH after metabolism is key. For instance, acidic citrus fruits like lemons become alkalizing in the body. The body maintains a stable blood pH regardless of diet.

Common High pH (Alkaline) Foods

Foods considered to have a high pH or an alkalizing effect (high PRAL score) are often plant-based.

Alkaline Vegetables

These include leafy greens like spinach (pH 6.6-7.2 when cooked) and kale, as well as broccoli, cucumbers (pH 7.5-8.0), celery, asparagus, and bell peppers.

Alkaline Fruits

Watermelon, avocado, ripe bananas, and even acidic fruits like lemons, limes, and grapefruit are considered alkalizing after digestion.

Alkaline Nuts, Seeds, and Legumes

Almonds, pumpkin seeds, lentils, soybeans, and tofu are also in this group.

Comparison of Alkaline vs. Acidic Foods


Food Category	Typical Alkaline Foods (High pH / Alkalizing Effect)	Typical Acidic Foods (Low pH / Acid-Forming)	Notes
Vegetables	Leafy greens (spinach, kale), broccoli, celery, cucumber	None (most are alkaline-forming)	Raw spinach is more alkaline than cooked.
Fruits	Watermelon, avocado, ripe bananas, lemons (metabolized)	Citrus (raw), most berries, pomegranates	Despite their initial acidity, many fruits are metabolically alkalizing.
Proteins	Almonds, tofu, most legumes (soybeans, lentils)	Most meats (beef, poultry, fish), dairy (cheese, milk)	Animal proteins leave an acidic ash after metabolism.
Grains	Quinoa, millet, wild rice	Wheat products (bread, pasta), most standard rice varieties	Sprouted grains are often more alkaline-forming.
Beverages	Herbal teas, mineral water, lemon water	Coffee, alcohol, sodas, sweetened fruit juices	Lemon water is alkalizing despite lemons being acidic.

The Role of pH in Digestion and Health

While the alkaline diet is popular, eating high-pH foods doesn't change blood pH, which the body tightly regulates. However, a diet rich in alkalizing plant-based foods offers health benefits, including antioxidants, fiber, and minerals, which can help reduce inflammation and support heart health. For acid reflux sufferers, consuming less acidic foods can alleviate symptoms.

pH in Food Processing and Safety

Food pH is crucial for safety and preservation, especially in canning. It dictates the heat needed to eliminate dangerous microbes like Clostridium botulinum, which cannot survive below pH 4.6. Low-acid foods require pressure canning, while high-acid foods can use a boiling water bath.

Conclusion

Understanding which food has a high pH level points to the broader concept of alkaline-forming foods. While few raw foods exceed a pH of 7, the metabolic effect of foods, particularly whole plant-based options, is what matters for an alkalizing diet. Incorporating more of these foods provides significant health benefits, from improved digestion to reduced inflammation.

Sources

WebMD: https://www.webmd.com/diet/alkaline-diets
NIH: https://pmc.ncbi.nlm.nih.gov/articles/PMC3195546/
OK State University: https://extension.okstate.edu/fact-sheets/the-importance-of-food-ph-in-commercial-canning-operations.html

Frequently Asked Questions

No, the alkaline diet does not change your body's blood pH. The body has a highly effective system to keep blood pH within a narrow, healthy range, and diet does not alter this.

Not in terms of their effect on the body. While most fruits are acidic in their raw state, many, like lemons and watermelons, have an alkalizing effect on the body after metabolism.

A food's pH is critical for safety, especially in canning. Low-acid foods (pH > 4.6) require pressure canning to destroy bacteria like Clostridium botulinum, whereas high-acid foods (pH < 4.6) can be processed with a boiling water bath.

Yes, for many individuals, eating more alkaline-forming foods, such as certain vegetables and fruits, can help manage acid reflux symptoms. It often involves balancing or limiting highly acidic trigger foods.

Common acid-forming foods include meat, dairy products (especially hard cheeses), many grains, processed foods, and sugary drinks.

A food's pH is its raw acidity or alkalinity level, while its metabolic effect is how the body responds after it has been digested and metabolized. Some acidic foods, like lemons, become alkaline-forming in the body.

Most vegetables have an alkaline-forming effect on the body. However, some can be slightly acidic, and their preparation (e.g., cooking) can sometimes alter their pH.