Can 10 Ounces of Prune Juice Cause Dehydration?
No, 10 ounces of prune juice will not dehydrate a person—it provides hydration and fluid intake, though it may have a mild laxative effect due to its sorbitol content.
Understanding Prune Juice Composition and Effects
Prune juice is primarily composed of water with dissolved sugars (sorbitol and fructose) and contains approximately 6.1 g of sorbitol per 100 g, which gives it mild laxative properties 1. The key distinction here is that prune juice adds fluid to the body, not removes it.
Hydration vs. Laxative Effect
- Prune juice contributes to total fluid intake and helps maintain hydration status, as it is fundamentally a water-based beverage 1
- The sorbitol in prune juice (approximately 18 g in 10 oz) draws water into the intestinal lumen, which softens stool and may increase stool frequency 2, 3
- This mechanism increases water content in the stool, but does not cause net body water loss that would lead to dehydration 2
When Prune Juice Is Recommended
- The American Academy of Pediatrics specifically recommends prune juice (along with pear and apple juice) for treating constipation in infants because the sorbitol increases stool frequency and water content 2, 3
- When provided in appropriate amounts (10 mL/kg body weight), prune juice is well-absorbed and does not cause malabsorption issues 2
Appropriate Beverage Selection for Hydration
- For general rehydration in healthy adults with simple low-intake dehydration, fruit juices (including prune juice) are acceptable beverages alongside water, tea, and other preferred fluids 4
- Fruit juices are appropriate for mild diarrhea without significant dehydration, as they provide both fluid and electrolytes 4
- Oral rehydration solutions are not indicated for simple dehydration from inadequate intake—they are specifically designed for electrolyte replacement during diarrheal illness 4
Important Caveats
- Excessive consumption of prune juice (well beyond 10 oz) could theoretically cause osmotic diarrhea due to high sorbitol content, which if severe and untreated, might lead to dehydration 2
- If someone develops significant diarrhea from any cause (including excessive prune juice intake) and does not replace fluid losses, dehydration could occur—but this is from the diarrhea itself, not the initial juice consumption 2
- The threshold for problematic sorbitol intake is considerably higher than 10 oz in most individuals 2
Clinical Bottom Line
Ten ounces of prune juice provides approximately 300 mL of fluid, which contributes positively to hydration status 1. While it may increase bowel movements due to sorbitol content, this normal laxative effect does not cause dehydration in healthy individuals consuming reasonable amounts 2, 3. The concern about dehydration would only arise if someone developed severe, prolonged diarrhea and failed to maintain adequate fluid intake to replace losses 2.