Food pH and Alkalinity Calculator
pH in foods determines whether they are acidic (<7), neutral (=7), or alkaline (>7). While the alkaline diet theory is controversial—your body regulates blood pH independently—food pH does impact dental health, acid reflux symptoms, and kidney stone formation. This calculator shows the pH of 15 common foods and beverages based on FDA and FAO measurements. It's useful for people managing gastritis, teeth grinding, cavities, or kidney health.
When to use this calculator
- You have acid reflux and want to avoid foods that trigger symptoms.
- You're getting frequent cavities and want to identify acidic drinks and foods.
- Your doctor mentioned acidic urine and you want to adjust your diet.
- You're curious about alkaline diet claims and want real data.
- You preserve food at home and need pH data for safe canning.
Example: Cola Soda vs. Pure Water
- Cola soda: pH = 2.5 (highly acidic).
- Pure water: pH = 7.0 (neutral).
- Cola is ~30,000× more acidic than water (logarithmic scale).
- Erodes tooth enamel with frequent consumption.
How it works
1 min readWhat is pH?
pH measures acidity or alkalinity on a 0–14 scale. It's logarithmic: each point = 10×.
Food pH Reference Chart
| Food | pH |
|---|---|
| Lemon | 2.3 |
| Cola soda | 2.5 |
| Vinegar | 2.9 |
| Apple | 3.5 |
| Tomato | 4.3 |
| Coffee | 5.0 |
| Banana | 5.0 |
| Red meat | 5.8 |
| Broccoli | 6.3 |
| Avocado | 6.4 |
| Spinach | 6.5 |
| Milk | 6.7 |
| Pure water | 7.0 |
| Almonds | 7.2 |
| Baking soda | 9.0 |
Source: FDA Food pH Database.
Health Impact
1. Tooth enamel: erodes at pH <5.5.
2. Acid reflux: foods with pH <4 worsen symptoms.
3. Kidney stones: acidic diets increase oxalate and uric acid risk.
4. Stomach: stomach pH is always 1.5–3.5; food doesn't change it.
The Alkaline Diet—Myth vs. Science
Myth: "Eating alkaline foods alkalinizes your blood."
Science: blood pH stays 7.35–7.45 due to homeostasis. Your urine pH does change, which can help people with uric acid kidney stones.
Key Takeaways
Consult a nutritionist or gastroenterologist for personalized dietary advice based on your health condition.
Frequently asked questions
Is the alkaline diet real?
Yes, as an eating style, but it doesn't change blood pH—blood pH is tightly regulated by your body. However, it does affect urine pH, which matters for some kidney stone types.
What's the most acidic food?
Pure lemon juice at pH 2.3 is among the most acidic common foods, followed by vinegar at 2.9.
Does diet really affect your blood pH?
No. Your body maintains blood pH at 7.35–7.45 regardless of diet. However, diet does change urine pH.
What pH erodes tooth enamel?
Tooth enamel starts to erode at pH below 5.5. Very acidic drinks like cola (pH 2.5) cause rapid erosion with frequent exposure.
Is diet soda less acidic than regular soda?
No. Diet soda is just as acidic (pH ~2.9–3.2) despite having no sugar. The phosphoric acid erodes enamel equally.
Can an alkaline diet prevent cancer?
No scientific evidence supports this. The WHO, NIH, and American Cancer Society do not recommend alkaline diets for cancer prevention.
How does food pH relate to acid reflux?
Very acidic foods (pH <4) can trigger or worsen acid reflux symptoms. People with reflux often do better choosing foods with pH >5.
What's the pH of mineral water?
Most mineral water has pH 7–8 (slightly alkaline). Branded 'alkaline water' can reach pH 9–10, though health benefits are debated.