Gastrointestinal bleeding is blood loss anywhere in the digestive tract from the esophagus to the rectum. It is caused by conditions like peptic ulcers, esophageal varices, inflammatory bowel disease, diverticulosis, or medication-induced damage from NSAIDs and acetaminophen. The Urea Nitrogen (BUN) test is the most important blood test for monitoring GI bleeding because it detects elevated levels when blood is digested and absorbed in the intestines.
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Gastrointestinal bleeding is caused by conditions that damage or erode the lining of the digestive tract. Peptic ulcers from Helicobacter pylori infection or NSAID use are common upper GI causes, while diverticulosis and colorectal polyps frequently cause lower GI bleeding. Esophageal varices from liver disease, inflammatory bowel disease (Crohn's disease and ulcerative colitis), and chronic use of blood thinners or high-dose acetaminophen can also trigger bleeding episodes throughout the digestive system.
The Urea Nitrogen (BUN) test is the most important blood test for gastrointestinal bleeding because it detects elevated BUN levels when blood is digested and absorbed in the intestines. This elevation helps healthcare providers assess the severity and location of bleeding, as upper GI bleeds typically cause more significant BUN increases. The BasoFunction™ HRT Acetaminophen test is also essential if medication-related bleeding is suspected, as it measures acetaminophen metabolism biomarkers that indicate whether chronic high-dose use is contributing to stomach bleeding and ulcer formation.
You should get tested if you notice black, tarry stools (melena), bright red blood in your stool, vomit that looks like coffee grounds, or if you experience persistent abdominal pain with dizziness or weakness. Testing is also important if you take NSAIDs, aspirin, or high doses of acetaminophen regularly and develop stomach discomfort, or if you have a history of ulcers, liver disease, or inflammatory bowel disease. Unexplained anemia with fatigue and pale skin may indicate slow, chronic bleeding that requires immediate evaluation.
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What this means
Your testosterone levels are slightly below the optimal range. While this is not necessarily cause for concern, it may contribute to occasional fatigue, reduced motivation, or lower muscle mass over time.
Recommended actions
Increase resistance or strength training
Prioritize 7–8 hours of quality sleep per night, try to reduce stress
Include more zinc- and magnesium-rich foods (like shellfish, beef, pumpkin seeds, spinach)
Consider retesting in 3–6 months
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