Tolerable Upper Intake Level
Quick Summary
The Tolerable Upper Intake Level (UL) is the highest daily nutrient intake that is unlikely to pose any risk of adverse health effects for nearly all individuals in the general population. This guideline is part of the broader Dietary Reference Intakes (DRIs) established in the United States and Canada to promote healthy eating and prevent excessive nutrient consumption.12
The UL is not intended for individuals under medical supervision. For most nutrients, habitual excess intake can lead to chronic toxicity, and even water can be toxic in very large quantities. The UL values are generally lower for infants, children, and adolescents compared to adults.23
Tolerable Upper Intake Level (UL) for Selected Nutrients for Adults:12
- Calcium: 2,500 mg
- Copper: 10 mg
- Fluoride: 10 mg
- Folic acid: 1,000 mcg
- Iodine: 1,100 mcg
- Iron: 45 mg
- Magnesium: 350 mg
- Manganese: 11 mg
- Niacin: 35 mg
- Phosphorus: 4 g
- Selenium: 400 mcg
- Vitamin A: 3,000 mcg (10,000 IU)
- Vitamin B6: 100 mg
- Vitamin C: 2,000 mg
- Vitamin D: 50 mcg (2,000 IU)
- Vitamin E: 1,000 mg
- Zinc: 40 mg
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