The Tolerable Upper Intake Level (UL) is the maximum daily amount of a nutrient that is unlikely to cause harmful effects in most people. It is established by health organizations to help prevent toxicity and adverse health effects from excessive intake of vitamins and minerals. The UL is particularly important for nutrients that can accumulate in the body, such as vitamin A and iron. The UL is not a recommended intake level but serves as a guideline for safe consumption. It is essential for individuals, especially those taking supplements, to be aware of the UL to avoid exceeding it and risking potential health issues.