The low FODMAP diet is a temporary eating plan designed to help manage the common symptoms associated with Irritable Bowel Syndrome (IBS). Many people with digestive sensitivities are confused when navigating dried fruits, which are often recommended for fiber but can be concentrated sources of fermentable carbohydrates. Prunes are a source of frequent inquiry for those following this diet due to their well-known laxative effects. The core question for anyone managing IBS symptoms is whether this popular dried fruit can be included in a low FODMAP eating pattern.
What Defines a Low FODMAP Food
FODMAP is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are small carbohydrates found in many foods that are poorly absorbed in the small intestine, particularly in individuals with IBS. Once they travel to the large intestine, gut bacteria rapidly ferment them, which produces gas. This fermentation, combined with the unabsorbed sugars drawing extra water into the intestines, causes physical symptoms such as bloating, abdominal pain, gas, and diarrhea.
The low FODMAP diet is a short-term process designed to identify specific food triggers, not a permanent lifestyle. It is structured around three distinct phases, beginning with a period of strict elimination. During this first stage, lasting two to six weeks, all high FODMAP foods are removed from the diet. If symptoms improve, the second phase, reintroduction, begins, where FODMAP groups are systematically tested one at a time to determine individual tolerance.
The final stage is personalization, where the individual creates a long-term diet by limiting only the specific FODMAPs that caused symptoms during testing. This strategic approach ensures the diet remains varied and nutritious, preventing unnecessary long-term food restrictions. Foods are classified as low, moderate, or high FODMAP based on laboratory testing, most notably by Monash University.
Prunes and Their FODMAP Classification
Prunes are classified as a high FODMAP food. This determination is made because the concentration of fermentable carbohydrates exceeds the low FODMAP threshold, even in small amounts. Official testing and classification by major authorities, such as Monash University, confirm that prunes should be avoided during the initial elimination phase of the diet.
The dried nature of prunes contributes significantly to their high FODMAP status. The process of drying plums removes water, which concentrates all the sugars and components, including the problematic FODMAPs. This concentration means that even a small serving contains a high load of fermentable carbohydrates that can trigger symptoms in sensitive individuals.
The fresh version of the fruit, plums, also presents a challenge. Plums contain FODMAPs, specifically the polyol sorbitol, and high amounts of excess fructose. Because prunes are dried plums, they carry an even higher concentration of these compounds, classifying them as a high FODMAP food for IBS management.
Navigating Serving Sizes and Individual Tolerance
The specific FODMAP component that makes prunes a high-risk food is the polyol sorbitol. Sorbitol is a sugar alcohol naturally present in many fruits, including apples, pears, and plums. Since sorbitol is poorly absorbed in the small intestine, it travels to the large intestine where it can draw water and be fermented, contributing directly to digestive symptoms. Prunes are also high in fiber; the combination of high sorbitol and high fiber strongly promotes a laxative effect, making them a common trigger for those with IBS.
For people who have completed the reintroduction phase, a very small quantity of prunes might be tolerable, but this must be determined individually. The concept of FODMAP “stacking” is a factor to consider even with foods that are low FODMAP in isolation. Stacking occurs when multiple servings of low or medium FODMAP foods are consumed in the same meal, causing the total FODMAP load to accumulate past an individual’s symptom threshold.
For example, a person might eat a low FODMAP serving of fruit and then combine it with another low FODMAP food containing the same type of polyol, leading to a problematic cumulative dose. Because prunes are already high in sorbitol, a low-FODMAP serving size is not viable, unlike other dried fruits. Raisins, in contrast, are considered low FODMAP in a very small serving size of about one tablespoon (13g), but exceeding this amount quickly raises the FODMAP content.
The goal of the diet is to liberalize restrictions over time, meaning a person might eventually tolerate a single prune or a half-serving mixed into a meal. However, this individual tolerance should only be tested during the personalization phase. It is recommended that this process be guided by a qualified dietitian. This professional guidance ensures that reintroduction is systematic and that the individual can safely gauge their sensitivity to sorbitol and other FODMAPs.