Does OJ Dehydrate You? The Truth About Orange Juice and Hydration

December 16, 2025 •

3 min read

Surprisingly, a study published in the American Journal of Clinical Nutrition found 100% orange juice to be more hydrating than plain water. This notion that OJ might dehydrate you is a common misconception that largely ignores its significant water and electrolyte content, focusing instead on its sugar.

Quick Summary

Pure orange juice is more hydrating than water due to its electrolytes, but its high sugar content necessitates moderate consumption. It's an effective rehydrator, especially after exercise.

Key Points

Hydrating, Not Dehydrating: 100% orange juice is primarily water and contains electrolytes, making it a net hydrating beverage.
Electrolytes Aid Absorption: The potassium in orange juice helps the body absorb and retain fluids more efficiently than plain water, which lacks electrolytes.
Sugar is the Main Concern: Excessive consumption of orange juice can be counterproductive due to its high natural sugar content, which can increase urination.
Moderation is Essential: To maximize hydration benefits and minimize the negative effects of sugar, 100% orange juice should be consumed in moderation as part of a balanced diet.
Effective Post-Exercise Drink: Studies show that 100% orange juice is as effective as water or sports drinks for rehydration and recovery after exercise.

Understanding the Myth: Is Orange Juice a Diuretic?

The misconception that orange juice is dehydrating often stems from a misunderstanding of how the body processes sugar and the mild diuretic effects of certain compounds. It's true that high sugar intake can lead to increased urination as the body works to flush out excess glucose, potentially leading to dehydration if consumed in excessive quantities. However, this effect is largely counteracted by the high water content and beneficial electrolytes found in 100% orange juice.

The Science of Orange Juice and Hydration

Far from being dehydrating, 100% orange juice is composed of approximately 90% water. Beyond just water, it contains a combination of naturally occurring sugars, vitamins, and minerals that aid in fluid absorption and retention. Scientists have even developed a tool called the 'beverage hydration index' to measure how effectively different drinks hydrate the body. Studies have shown that orange juice ranks higher than plain water on this index, performing similarly to milk and oral rehydration solutions.

This is primarily due to its electrolyte content, which is crucial for maintaining fluid balance and muscle function. While plain water is essential, it lacks these mineral ions. When consumed in moderation, the electrolytes in orange juice, such as potassium, help the body absorb and retain water more efficiently.

The High-Sugar Conundrum

The most significant drawback of relying on orange juice for hydration is its high sugar content. Even without added sugars, a single 8-ounce glass contains a considerable amount of natural sugar. The body uses water to metabolize this sugar, so if you consume too much, particularly without other sources of hydration, the high sugar load can indeed diminish some of the hydrating benefits. For healthy individuals, a glass of orange juice isn't going to cause dehydration, but relying on it as a primary fluid source or consuming it excessively is not recommended.

Smart Ways to Incorporate Orange Juice for Hydration

Dilute with water: For a lower-sugar, flavorful drink, try mixing 100% orange juice with an equal amount of water. This is a great way to get electrolytes without the full sugar load.
Replenish after exercise: After an intense workout, orange juice is an effective post-exercise rehydration tool. The combination of natural sugars for quick energy and electrolytes for fluid replacement makes it a comparable option to sports drinks, as studies have shown.
Freeze into popsicles: For a refreshing, hydrating summer treat, freeze 100% orange juice into popsicles. This is a kid-friendly way to boost fluid intake.

Comparison of Hydrating Beverages


Feature	100% Orange Juice	Plain Water	Sports Drinks
Hydration Index	Higher than water due to electrolytes and natural sugars	Baseline for hydration index; lacks electrolytes	Can be higher than water, but varies greatly by brand and formula
Sugar Content	High (naturally occurring), can be detrimental in excess	Zero grams	Often high (added sugars); lower-sugar options exist
Electrolyte Source	Potassium and magnesium	None naturally unless from a mineral-rich source	Added electrolytes like sodium and potassium
Best Use Case	Post-exercise recovery in moderation, or diluted for general hydration	Everyday hydration, no added calories or sugar	Intense, prolonged exercise to replenish lost electrolytes
Key Considerations	Moderation is key due to sugar content; check for 100% juice only	Most efficient for general hydration; no nutritional extras	Can have very high sugar; not ideal for casual hydration

Conclusion

In conclusion, the claim that orange juice dehydrates you is a myth driven by an oversimplification of its effects. While high sugar intake from any source can stress the body's fluid balance, 100% orange juice is inherently hydrating due to its high water content and beneficial electrolytes like potassium and magnesium. For general, day-to-day hydration, plain water remains the most straightforward and healthiest option. However, in moderation, or for targeted rehydration after exercise, 100% orange juice is an effective and nutrient-rich choice. The key lies in consuming it mindfully as part of a balanced and healthy hydration strategy, rather than treating it like plain water. A smart approach is to limit intake to a reasonable portion size or to dilute it to reduce the sugar concentration. For an in-depth look at the science of beverage hydration, studies published in reputable journals like the American Journal of Clinical Nutrition provide valuable insights.

Frequently Asked Questions

Yes, 100% orange juice is good for hydration because it has high water content (almost 90%) and contains electrolytes like potassium, which aid in fluid balance and retention.

The myth comes from its sugar content. Consuming large amounts of sugar can cause the body to increase urination to flush out the excess, which can lead to fluid loss. However, this is primarily a risk with overconsumption.

Studies using a beverage hydration index have shown that 100% orange juice can be more hydrating than plain water due to its combination of water, sugars, and electrolytes that improve fluid retention.

To minimize the impact of sugar, drink orange juice in moderation, typically an 8-ounce serving per day. You can also dilute it with water to reduce the overall sugar concentration while maintaining the flavor and electrolyte benefits.

Yes, 100% orange juice can be a viable option for post-exercise rehydration. The combination of natural carbohydrates provides energy, and the electrolytes help replenish what was lost during physical activity.

The key difference is the nutritional content. Water provides fluid without added calories or sugar, making it the most basic form of hydration. Orange juice provides fluids along with electrolytes and sugars, which can be beneficial in certain situations, but require mindful consumption due to the sugar.

Yes, but moderation is key. A single 8-ounce serving of 100% orange juice can provide valuable nutrients like Vitamin C and potassium. It's best to balance juice intake with whole fruits and other hydration sources like plain water.