Stool for pH & Reducing Substances

Stool (feces) samples can provide valuable information about gut and digestive system health, especially in cases of malabsorption or digestive illnesses. The Stool for pH & Reducing Substances test is a painless and noninvasive method to detect undigested sugars or other substances, such as fatty acids, in the stool, which can suggest gastrointestinal disorders such as lactose intolerance, carbohydrate malabsorption, or bacterial overgrowth. This test helps pinpoint these underlying issues by identifying imbalances in the digestive process.

The stool's pH might help in understanding the microbial status of the intestine. Typically, the pH of the stool is slightly acidic (meaning healthy digestion), but a low pH might indicate bacterial overgrowth that kills other types of bacteria or does not metabolize carbohydrates, while a high stool pH usually indicates a lack of healthy gut bacteria, or a metabolic issue related to fatty acids. In contrast, reducing substances in the stool are unabsorbed sugars that have not been completely absorbed by the body during the digestion process. The reducing sugars can be glucose or lactose, which may appear in the stool in conditions like lactose intolerance or malabsorption syndromes.

Testing for Stool for pH & Reducing Substances may be considered if symptoms such as chronic diarrhea, bloating, abdominal pain, or unexplained weight loss are present. Doctors may also use this test to monitor the efficacy of dietary changes, current digestive complaints, or malabsorption. The test may also be helpful for differentiating between different causes of digestive symptoms — for example, between lactose intolerance and other forms of carbohydrate malabsorption.

For this test, collect a fresh stool sample in a clean, sterile, leak-proof, screw-capped container, preferably one with a spoon. Only a small portion of about 5–10 grams (1–2 teaspoons) is needed, so avoid overfilling the container. Do not use matchboxes, paper, or other absorbent materials for collection. Ensure the sample is not contaminated with urine or water. Notify the doctor about any medications or supplements, as these may affect the test results.

Test result ranges are approximate and may differ slightly between labs, depending on the methodology and laboratory guidelines. Discuss specific test results with the doctor. Provide a complete medical history to help the doctor correlate clinical and laboratory findings. The results will help determine the medical condition, and formulate the treatment plan.