Most fruits are acidic, with pH levels falling between 2.0 and 5.0 on a scale where 7.0 is neutral. Lemons and limes sit at the extreme end (pH 2.0–2.8), while bananas, melons, and avocados are among the few fruits that land closer to neutral. Understanding where common fruits fall on this spectrum matters for your teeth, your digestion, and how you choose to eat them.
The Most Acidic Fruits (pH Below 3.0)
The fruits with the lowest pH pack the sharpest punch, and you can usually taste it. Lemons and limes top the list, with lemon juice measuring pH 2.0–2.6 and lime juice pH 2.0–2.35. These are among the most acidic foods you’ll encounter in a kitchen.
Several fruits you might not expect land in this highly acidic range. Concord and Niagara grapes measure pH 2.80–3.27, considerably more acidic than many people realize. Blue plums come in at 2.80–3.40, pomegranates at 2.93–3.20, and loganberries at 2.70–3.50. Cranberries, grapefruit (pH 3.00–3.75), and strawberries (pH 3.00–3.90) also dip into this territory.
Moderately Acidic Fruits (pH 3.0–4.5)
This is where most popular fruits cluster. The moderate range includes many everyday staples:
- Apples: pH 3.30–4.00, varying by variety (McIntosh at 3.34 is more acidic than Delicious at 3.9)
- Blueberries: pH 3.12–3.33
- Pineapple: pH 3.20–4.00
- Peaches: pH 3.30–4.05
- Raspberries: pH 3.22–3.95
- Oranges: pH 3.69–4.34
- Mangoes (ripe): pH 3.40–4.80
- Pears: pH 3.50–4.60
- Cherries: pH 4.01–4.54
- Nectarines: pH 3.92–4.18
- Apricots: pH 3.30–4.80
- Blackberries: pH 3.85–4.50
Notice the wide ranges. A single fruit type can span a full pH point depending on variety, growing conditions, and ripeness. A tart Granny Smith apple is a different experience from a sweet Fuji, and the pH reflects that.
Low-Acid and Near-Neutral Fruits
A small group of fruits sit well above the acidic range, closer to neutral on the pH scale. These are the ones that matter most if you’re trying to limit acid intake:
- Cantaloupe: pH 6.13–6.58
- Honeydew melon: pH 6.00–6.67
- Avocado: pH 6.27–6.58
- Watermelon: pH 5.18–5.60
- Papaya: pH 5.20–6.00
- Bananas: pH 4.50–5.20
- Tomatoes: pH 4.30–4.90
Bananas and melons are specifically recommended as safe choices for people managing acid reflux. Green (unripe) mangoes are also surprisingly neutral at pH 5.80–6.00, far less acidic than their ripe counterparts.
What Makes Fruit Acidic
The sour taste in fruit comes from organic acids, primarily citric acid and malic acid. Citrus fruits rely heavily on citric acid, which dominates the pulp in ripe oranges, lemons, and grapefruit. Apples and stone fruits lean more on malic acid. Most fruits contain a blend of several organic acids, including smaller amounts of tartaric acid, oxalic acid, and naturally occurring vitamin C.
Ripening generally reduces acidity. As a fruit matures, its sugar content rises while its total acid content drops, shifting the balance toward sweetness. This is why a ripe peach tastes mellower than a firm one picked early. The green mango example is an interesting exception: it starts near neutral (pH 5.80–6.00) and actually becomes more acidic as it ripens to pH 3.40–4.80, as citric acid accumulates in the flesh.
Acidic Fruits and Your Teeth
Tooth enamel begins to soften when exposed to a pH below about 5.5, which means nearly every fruit on this list is acidic enough to affect enamel over time. But pH alone doesn’t tell the whole story. The total acid content of a food, not just the concentration of free acid, plays a bigger role in how much damage actually occurs. A fruit with a moderate pH but high total acid can be more erosive than one with a lower pH and less acid overall.
Citric and malic acids are the primary culprits in fruit-related enamel erosion. Fruit juices tend to be worse than whole fruit because the liquid bathes your teeth more thoroughly and lingers in the mouth longer. Drinking acidic juice through a straw, rinsing with water afterward, or waiting at least 30 minutes before brushing (to avoid scrubbing softened enamel) are practical ways to reduce the effect.
Acidic pH Doesn’t Mean Acid-Forming
One of the most counterintuitive facts about fruit acidity: a fruit can be highly acidic going in and still have an alkalizing effect on your body once digested. When researchers measure the actual metabolic impact of foods using a system called potential renal acid load (PRAL), nearly every fruit scores as base-forming, meaning it shifts your body chemistry in an alkaline direction.
Raisins have one of the strongest alkalizing effects of any food, with a PRAL value of -21.0 (the more negative, the more alkalizing). Apricots score -4.8, kiwi -4.1, oranges -2.7, and strawberries -2.2. Even lemon juice, with its intensely acidic pH of 2.0–2.6, scores -2.5 on the PRAL scale, meaning it is alkaline-forming once metabolized. This is because the organic acids in fruit are broken down during digestion, leaving behind alkaline mineral compounds.
So if you’ve heard claims that lemons are “alkalizing,” that’s technically accurate in terms of their metabolic effect, even though the juice itself is strongly acidic.
How Processing Changes Acidity
Cooking, canning, and juicing can shift pH in either direction. Applesauce (pH 3.10–3.60) often measures slightly more acidic than a fresh eating apple (pH 3.30–4.00) because cooking concentrates the acids and added ingredients can lower pH. Canned cherries packed in water (pH 3.25–3.82) are more acidic than fresh California cherries (pH 4.01–4.54), partly because the packing liquid absorbs acid from the fruit.
Orange juice (pH 3.30–4.19) falls in roughly the same range as whole oranges (pH 3.69–4.34) but tends to skew toward the lower, more acidic end. Frozen blueberries (pH 3.11–3.22) are slightly more acidic than fresh ones (pH 3.12–3.33), though the difference is minimal. In general, processed fruit products land at the more acidic end of their fresh counterparts’ range, making whole fruit the gentler option for anyone watching their acid intake.