Tolerable Upper Intake Level (UL)
Also known as UL, Upper limit
The highest daily intake of a nutrient that is unlikely to cause harm in most people.
The UL is a safety ceiling. Staying below it makes adverse effects unlikely, while regularly exceeding it raises the risk of toxicity, especially for fat-soluble vitamins and trace minerals that accumulate.
Always weigh a supplement's dose against its UL, and remember that intake adds up across food, fortified products, and multiple supplements.