Which is the most acidic fruit juice?

November 21, 2025 •

4 min read

With an approximate pH level as low as 2.0, lemon juice is a strong contender for the title of the most acidic fruit juice. Understanding the acidity of different juices can be crucial for managing health concerns such as acid reflux and protecting tooth enamel from erosion.

Quick Summary

The acidity of various fruit juices, measured by the pH scale, can significantly affect dental health and digestion. Extremely acidic juices like lemon and lime have the lowest pH, while others like orange and apple are less so. Consumers can learn about specific pH values to make informed choices.

Key Points

Lemon and lime juice are the most acidic: With pH levels potentially as low as 2.0, these citrus juices have the highest acidity among common fruit juices.
Acidity can cause dental erosion: The low pH of these juices can soften and wear down tooth enamel, increasing sensitivity and cavity risk.
Acid reflux can be triggered: For those with GERD, highly acidic juices can irritate the esophagus and worsen symptoms.
Dilution is an effective strategy: Mixing juice with water can lower its acidity, making it less harsh on the teeth and stomach.
Choose lower-acid alternatives: Juices like pear, peach, and watermelon have higher pH levels and are gentler on the digestive system.

Understanding the pH Scale and Fruit Juice Acidity

Acidity is measured using the pH scale, which ranges from 0 to 14. A pH of 7 is neutral (pure water), values below 7 are acidic, and values above 7 are alkaline. The scale is logarithmic, meaning each whole number change represents a tenfold difference in acidity. For example, a juice with a pH of 3 is ten times more acidic than one with a pH of 4. Most fruit juices are naturally acidic due to the presence of organic acids like citric, malic, and ascorbic acid.

The sour taste we associate with citrus fruits, in particular, is a direct result of their high citric acid content. However, acidity is not just about taste; it has real health implications, particularly for dental enamel and individuals with sensitive digestive systems.

And the Most Acidic Fruit Juice Is...

While many people might guess lemon juice, the title for the most acidic fruit juice is often a close race between lemon juice and lime juice. Multiple reputable sources confirm that these two citrus giants have the lowest pH range among common fruit juices.

Lemon Juice: Typically has a pH range of 2.0 to 2.6. This extremely low pH is due to its high concentration of citric acid, which can be up to 8%.
Lime Juice: Shares a very similar, and sometimes even lower, pH range, typically between 2.0 and 2.35. The total acid content is also comparable to lemons.

Another surprisingly acidic fruit juice is cranberry juice. Unsweetened varieties can have a pH as low as 2.3, making them highly acidic and often comparable to or slightly less acidic than pure lemon or lime juice. The pH level in cranberry juice, especially commercial cocktails, can vary widely based on added sugars and other ingredients.

Comparison of Common Fruit Juice Acidity

To put the acidity of various fruit juices into perspective, here is a comparison table based on typical pH ranges reported by sources like Clemson University.


Fruit Juice	Typical pH Range	Primary Acid	Notes
Lemon Juice	2.00–2.60	Citric Acid	Very high citric acid content; most acidic.
Lime Juice	2.00–2.35	Citric Acid	Extremely acidic, closely rivaling lemon juice.
Cranberry Juice	2.30–2.52	Citric Acid, Malic Acid	Can vary based on brand and added sugars.
Grapefruit Juice	3.00–3.75	Citric Acid	A popular but still highly acidic choice.
Pineapple Juice	3.20–4.00	Citric Acid	Also contains bromelain enzyme.
Apple Juice	3.30–4.00	Malic Acid	Less acidic than citrus, but still low pH.
Orange Juice	3.69–4.34	Citric Acid	pH can vary with orange variety and ripeness.
Peach Juice	3.30–4.05	Malic Acid	Considered a lower-acid option relative to citrus.
Pear Juice	3.50–4.60	Malic Acid	Often recommended for low-acid diets.
Watermelon Juice	5.20–5.60	Citric Acid	One of the least acidic juices.

The Impact of Acidic Juices on Your Health

While acidic fruits and juices are often rich in beneficial nutrients like vitamin C, their low pH levels pose potential health risks, primarily to dental and digestive health.

Dental Erosion: The high acid content in these juices can soften and wear down tooth enamel over time. This leaves the sensitive dentin layer exposed, leading to increased tooth sensitivity and a higher risk of cavities. Dentists recommend waiting at least 30 minutes after consuming acidic foods before brushing your teeth to give enamel a chance to resettle.
Acid Reflux and GERD: For individuals who suffer from gastroesophageal reflux disease (GERD), highly acidic drinks can trigger or worsen symptoms. Citrus and tomato juices are common culprits, irritating the esophageal lining and contributing to heartburn and indigestion.

How to Mitigate the Effects of Acidic Juices

Fortunately, you don't have to completely abandon acidic juices. Several strategies can help reduce their negative effects:

Dilute with Water: Mixing juice with water lowers its acidity, making it gentler on your teeth and stomach. This is a simple and effective method for those with sensitivity issues.
Use a Straw: Drinking juice through a straw minimizes direct contact with your teeth, protecting the enamel.
Pair with Alkaline Foods: Consuming acidic juice with alkaline foods, such as cheese, nuts, or bananas, can help neutralize the acid in your mouth and stomach.
Rinse with Water: After drinking, rinsing your mouth with water can help wash away the acid and restore your mouth's natural pH balance.
Choose Lower-Acid Options: If you are particularly sensitive, opting for less acidic juices like pear or watermelon can provide hydration and nutrients without the high acid load.

Conclusion

For those wondering which is the most acidic fruit juice, the data consistently points to lemon and lime juice, with pH values often dropping to 2.0 or lower. While offering nutritional benefits, their high acidity requires mindful consumption to protect against dental erosion and digestive discomfort. By understanding the relative acidity of various juices and implementing simple mitigating strategies, you can continue to enjoy a variety of juices responsibly. For further information on oral hygiene and the effects of acidic foods, consult resources like the Colgate Oral Health website.

Frequently Asked Questions

Yes, unsweetened cranberry juice is highly acidic, with a pH range often comparable to citrus juices. However, commercial cranberry juice cocktails are often mixed with water and sugar, which can slightly raise the pH.

Yes, regular consumption of highly acidic juices can weaken and erode tooth enamel over time. This makes teeth more susceptible to sensitivity and decay.

Yes, several fruit juices are less acidic than citrus options. Juices from fruits like pear, watermelon, and some types of apples are considered lower in acid.

Adding a small pinch of baking soda can neutralize acidity in a glass of juice. However, this method should be used sparingly, as excessive consumption of baking soda can have other health implications.

Using a straw, rinsing your mouth with water after drinking, and waiting at least 30 minutes before brushing your teeth are effective ways to protect your enamel from acid.

While not the direct cause, highly acidic juices can irritate the esophagus and trigger or worsen symptoms of acid reflux, especially in individuals with GERD.

The pH scale provides a standardized measurement for acidity, allowing for accurate comparison between different juices. It helps consumers understand the potential effects on their health, such as dental erosion and digestive issues.