Yes, Fuji apples are acidic, but their sweetness hides it well. In a 2018 study of 11 apple varieties, Fuji measured pH 3.21 to 3.34 with about 5.3 to 6.6 grams of total acid per liter of juice (Mezey and Serralegri, 2018). That’s a moderate acid level, similar to Gala and well below tart apples like Granny Smith. What sets Fuji apart is sugar: it had the highest sugar reading of every apple in that study, about 14.4 °Brix (Mezey and Serralegri, 2018).

So what does that mean for acid reflux? Fuji is one of the lower-risk apple choices, thanks to its moderate acid. But sweet doesn’t mean acid-free, and no apple is guaranteed to be reflux-safe. This guide breaks down Fuji’s pH, why it tastes so sweet, how it compares with other apples, and how to enjoy it if you’re prone to heartburn.

Key Takeaways

• Fuji apples are acidic, with a pH of about 3.2 to 3.3 in one study.
• Their acid is moderate, about the same as Gala, roughly half to two-thirds of Granny Smith’s, and less than Pink Lady’s.
• Fuji is one of the sweetest apples. It had the highest sugar of 11 varieties in one study and the most sugar per 100 grams of the USDA apple entries we compared.
• Sweetness masks acid. Fuji tastes mild, but it still has a pH well below neutral.
• For reflux, Fuji is one of the gentler apple choices, though individual triggers vary.
• Because Fuji is high in natural sugar, it’s smart to pair it with protein if you’re watching blood sugar.

For other varieties, see our guides to Gala, Honeycrisp, Pink Lady, and Granny Smith, or start with Are Apples Acidic?

Are Fuji Apples Acidic or Alkaline?

Fuji apples are acidic. On the pH scale, anything below 7 is acidic, 7 is neutral, and anything above 7 is alkaline. Fuji juice measured pH 3.21 to 3.34 in the 2018 study (Mezey and Serralegri, 2018).

Like all apples, Fuji’s tang comes mainly from malic acid. Fuji just has a lot of sugar to balance it.

What about apples being “alkaline-forming”?

Apples often appear on “alkaline food” lists. That label describes the estimated acid load a food leaves after digestion, not its pH. Most fruits and vegetables are considered alkaline-forming because of their potassium and other minerals (Remer and Manz, 1995). Either way, food doesn’t change your blood pH, which your body keeps at about 7.35 to 7.45 (Hopkins et al., StatPearls).

What Is the pH of Fuji Apples?

Fuji isn’t listed separately in the FDA’s food pH table, but several studies have measured it.

Study 1: The 2018 apple comparison

Researchers measured Fuji apples from both organic and conventional farms (Mezey and Serralegri, 2018):

Source: Mezey and Serralegri, Athens Journal of Sciences, 2018.

The authors noted that Fuji had the highest soluble solids (14.41 °Brix) and total sugar content of the apples tested.

Study 2: Fuji juice from Brazil

A study of juices from Brazilian Fuji and Gala apples found Fuji’s titratable acidity averaged about 0.25 grams per 100 mL, ranging from roughly 0.14 to 0.43. Fuji also had more reducing sugar than Gala, about 12.75 vs. 11.06 grams per 100 mL (Vieira et al., 2011).

Study 3: Fuji among Chinese apple cultivars

A 2023 study of 15 apple cultivars grown in China found that Shandong Fuji had the second-highest soluble solids, 15.60 °Brix, of all the cultivars tested (Zhang et al., 2023).

What the studies agree on

• Fuji’s pH is about 3.2 to 3.3, typical for apples.
• Its acid is moderate, not especially high or low.
• Its sugar is consistently high, often the highest in the group.

Why Fuji Apples Taste So Sweet

Fuji’s sweetness comes from high sugar combined with moderate acid. USDA FoodData Central lists raw Fuji apples at about 13.3 grams of sugar per 100 grams, the most of the USDA apple entries we compared (USDA FDC 1750340):

Sources: USDA FoodData Central Foundation Foods: Fuji (1750340), Honeycrisp (1750343), Gala (1750341), Granny Smith (1750342).

Most of Fuji’s sugar is fructose (about 8.6 grams per 100 grams), the main sugar in apples.

The sugar-to-acid balance

How sweet an apple tastes depends on its balance of sugar and acid. Using the 2018 study’s conventional samples, we divided each apple’s sugar reading (°Brix) by its total acid (g/L) to get a rough sugar-to-acid ratio. A higher number means the apple tastes sweeter relative to its acidity:

Calculated from conventional-production data in Mezey and Serralegri, 2018. These ratios are our own simple calculation for comparison, not values reported by the study.

Fuji isn’t the lowest-acid apple. Golden Delicious, Red Delicious, Red Chief, and Envy have less. But Fuji pairs moderate acid with the most sugar, which is why so many people describe it as one of the sweetest apples available.

Where Fuji came from

Fuji was developed in Japan. Researchers at the Tohoku Agricultural Experiment Station in Fujisaki, Aomori Prefecture, crossed Ralls Janet and Delicious (Red Delicious) and introduced the result in 1962. It was named after Fujisaki and Mount Fuji, and by 1990 it made up about half of Japan’s apple production (Sawamura et al., Plant Disease, 1993). Its Red Delicious parent is one of the lowest-acid apples, which may help explain Fuji’s mild, sweet character.

Sweetness Can Hide Acidity

This is the most important point for anyone with heartburn or sensitive teeth: your taste buds read the balance of sugar and acid, not the pH.

Fuji tastes mild because its sugar overpowers the sour notes. But its pH of about 3.2 to 3.3 is nearly the same as much tarter apples. For example, Granny Smith measured pH 3.12 to 3.20 in the same study (Mezey and Serralegri, 2018). The real difference is total acid: Granny Smith had about 1.6 to 1.9 times as much.

We’ve seen this pattern with other foods too. Sweet cherry tomatoes, for example, can contain plenty of acid despite tasting sweet. The lesson: don’t judge acidity by taste alone.

Fuji vs. Other Apples: Acidity Comparison

Here’s how Fuji compares with nine other varieties in the 2018 study (Mezey and Serralegri, 2018):

Source: Mezey and Serralegri, Athens Journal of Sciences, 2018, Tables 3 and 4.

Fuji vs. Gala

They’re almost twins on acidity. In the 2018 study, Fuji and Gala had nearly identical pH and total acid, and the Brazilian juice study found similar average acidity for both (Vieira et al., 2011). The difference is sugar: Fuji consistently tested sweeter. See Are Gala Apples Acidic?

Fuji vs. Honeycrisp

Honeycrisp wasn’t in the 2018 study. Other research found Honeycrisp juice at about pH 3.11 at harvest (Gao and Rupasinghe, 2012), with titratable acidity of 0.3% to 0.7% at harvest (Good Fruit Grower). Since the numbers come from different studies, the comparison is approximate, but Fuji is generally in a similar or slightly milder range, and it has more sugar per USDA (13.3 g vs. 12.4 g per 100 g). See Are Honeycrisp Apples Acidic?

Fuji vs. Pink Lady

Pink Lady had about 24% to 40% more total acid than Fuji in the 2018 study. Pink Lady tastes sweet-tart, while Fuji tastes sweet. See Are Pink Lady Apples Acidic?

Fuji vs. Granny Smith

Granny Smith had about 1.6 times (conventional) to 1.9 times (organic) as much total acid as Fuji, and less sugar. That’s why Granny Smith tastes sour and Fuji tastes sweet. See Are Granny Smith Apples Acidic?

Fuji vs. other foods

Sources: FDA, Approximate pH of Foods and Food Products; Fuji value from Mezey and Serralegri, 2018.

For a complete list, see our guide to acidic foods.

Fuji Apples and Reflux Risk

So how risky are Fuji apples if you have acid reflux or GERD? Here’s a realistic picture.

The good news

• Apples aren’t a common trigger. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) lists citrus fruits, tomatoes, alcohol, chocolate, coffee and caffeine, high-fat foods, mint, and spicy foods as foods that may worsen reflux. Apples aren’t on that list (NIDDK).
• Fuji has moderate acid. It contains less acid than Granny Smith, Pink Lady, Kanzi, and Braeburn, which makes it one of the gentler apple choices.
• Fuji is naturally low in fat, and fat is one of the foods NIDDK lists as a possible trigger.

The caveats

• Sweet doesn’t mean acid-free. Fuji’s pH is still about 3.2 to 3.3.
• Triggers are personal. The American College of Gastroenterology’s 2022 guideline recommends that people with GERD identify their own trigger foods (Katz et al., 2022). Some people react to any acidic fruit.
• No apple treats reflux. There’s no research showing that Fuji, or any apple, prevents or relieves heartburn.

Our take on Fuji’s reflux risk

Among common apples, Fuji sits in the lower-risk group, alongside Gala, Golden Delicious, Red Delicious, and Envy. Tart apples like Granny Smith and Pink Lady are more likely to bother acid-sensitive people. For a full ranking, see our guide to GERD-friendly apple varieties.

Tips for eating Fuji apples with reflux

1. Eat them with a meal or snack, such as with oatmeal, yogurt, or cottage cheese.
2. Keep portions moderate, like half an apple to start.
3. Avoid eating close to bedtime. NIDDK suggests eating meals at least 3 hours before lying down if you have nighttime symptoms (NIDDK).
4. Watch apple drinks. Apple juice has a pH of 3.35 to 4.00 (FDA) and is easy to overdo. See Is Apple Cider Safe for Acid Reflux?
5. Track your symptoms in a simple food diary.

For more, read foods to avoid with GERD. If you have heartburn more than twice a week, trouble swallowing, or symptoms that don’t improve, see your doctor.

Fuji Apples and Your Teeth

Fuji combines natural sugar with moderate acid, so frequent snacking can expose your teeth to both. The American Dental Association recommends eating acidic foods as part of a meal, not by themselves, rinsing with water or having milk or cheese afterward, and waiting about an hour before brushing (American Dental Association).

A Fuji apple with a piece of cheese is a simple, tooth-friendly snack. Read more in Are Apples Good for Your Teeth?

Fuji Apples and Blood Sugar

Because Fuji is one of the sweetest apples, people managing blood sugar often ask about it. A few practical points:

• Fuji has more sugar per 100 grams than Gala, Honeycrisp, or Granny Smith, according to USDA data. The difference is a couple of grams, so portion size matters more than variety.
• Whole apples include fiber, about 2.1 grams per 100 grams of Fuji with skin (USDA FDC 1750340).
• Pairing apples with protein or fat, like nuts or cheese, is a common way to make a more balanced snack.

For more, see Are Apples Good for Diabetics? If you have diabetes, your doctor or a registered dietitian can help you fit fruit into your meal plan.

Cooking and Baking with Fuji Apples

Fuji’s sweetness makes it a natural choice for snacking, salads, and desserts:

• Raw snacking: Crisp, juicy, and sweet, it’s a favorite fresh-eating apple.
• Salads and slaws: Thin Fuji slices add sweetness without much tang.
• Baking: Because Fuji is so sweet, you may be able to use a little less added sugar in recipes. For more tang, mix it with a tarter apple like Granny Smith.

Cooking doesn’t remove an apple’s acid. The FDA lists applesauce at pH 3.10 to 3.60 (FDA).

Recipes to try with Fuji apples

• Honeycrisp apple salad: Fuji makes a sweet substitute.
• Maple apple muffins: Sweet Fuji pairs well with maple.
• Apple cinnamon raisin pancakes: A cozy weekend breakfast.
• Pumpkin apple scones: A fall favorite.
• Apple cupcakes with apple spice buttercream: A sweet treat for apple lovers.

A sprinkle of cinnamon complements Fuji’s natural sweetness.

Are Fuji Apples Healthy?

Yes. Fuji apples are a low-fat fruit with fiber and natural sugars. Here’s what USDA FoodData Central lists for 100 grams of raw Fuji with skin (USDA FDC 1750340):

Tip: Keep the skin on for more fiber.

Frequently Asked Questions

Are Fuji apples acidic or alkaline?

Fuji apples are acidic, with a pH of about 3.21 to 3.34 in one study. Like most fruits, apples are considered alkaline-forming after digestion, but that doesn’t change your blood pH.

What is the pH of a Fuji apple?

About 3.2 to 3.3. In a 2018 study, conventional Fuji apples measured pH 3.21 and organic Fuji apples measured pH 3.34.

Are Fuji apples less acidic than other apples?

Fuji has less acid than Granny Smith, Pink Lady, Kanzi, and Braeburn, and about the same as Gala. Golden Delicious, Red Delicious, Red Chief, and Envy contain slightly less.

Are Fuji apples good for acid reflux?

They’re one of the gentler apple choices because of their moderate acid, but no apple treats reflux. Eat them with meals and in moderate portions.

Why are Fuji apples so sweet?

Fuji combines high sugar, about 13.3 grams per 100 grams according to USDA, with only moderate acid. It had the highest sugar of 11 varieties in one study.

Is Fuji or Gala less acidic?

They’re nearly the same. Studies found very similar pH and total acid for Fuji and Gala. Fuji usually tastes sweeter.

Is Fuji or Honeycrisp better for acid reflux?

Both have moderate acid. Fuji is generally in a similar or slightly milder range, but individual apples vary. Try each and see how you feel.

Are Fuji apples healthy?

Yes. They’re low in fat, provide fiber, and make a satisfying snack. Because they’re high in natural sugar, pair them with protein if you’re watching blood sugar.

The Bottom Line

Fuji apples are acidic, with a pH of about 3.2 to 3.3, but their high sugar content makes them taste sweet and mild. Their total acid is moderate, about the same as Gala, roughly half to two-thirds of Granny Smith’s, and less than Pink Lady’s.

For people with acid reflux, Fuji is one of the lower-risk apple choices, but it isn’t acid-free, and triggers vary from person to person. Enjoy Fuji apples with meals, keep portions reasonable, and pay attention to how your body responds.

Want to compare more apples? Read Are Gala Apples Acidic?, Are Honeycrisp Apples Acidic?, Are Pink Lady Apples Acidic?, Are Granny Smith Apples Acidic?, or Are Apples Acidic?

Medical disclaimer: This article is for general information only and isn’t a substitute for professional medical or dental advice. If you have frequent heartburn, GERD, diabetes, or dental sensitivity, talk with your doctor, dentist, or a registered dietitian.

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