How much vitamin C should you take? continued...
Although many people take much higher doses of vitamin C, it's not clear that high doses have any benefit. Some studies have found that doses above 200 milligrams are not utilized by the body. Instead, the extra vitamin C is excreted in urine.
The tolerable upper intake levels of a supplement are the highest amount that most people can take safely. Higher doses might be used to treat vitamin C deficiencies. But don't take more unless a doctor says so.
|
Category |
Tolerable Upper Intake Levels (UL) of Vitamin C |
|
1-3 years |
400 mg/day |
|
4-8 years |
650 mg/day |
|
9-13 years |
1,200 mg/day |
|
14-18 years |
1,800 mg/day |
|
19 years and up |
2,000 mg/day |
Can you get vitamin C naturally from foods?
Many people get enough vitamin C from their diets. All fruits and vegetables have some vitamin C. Some of the best sources are:
- Green peppers
- Citrus fruits and juices
- Strawberries
- Tomatoes
- Broccoli
- Sweet potatoes
Light and heat can reduce vitamin C levels. Fresh and uncooked fruits and vegetables have the most vitamin C.
What are the risks of taking vitamin C?
- Side effects. At recommended doses, vitamin C supplements are safe. However, they can cause upset stomach, heartburn, cramps, and headaches in some people. High doses of vitamin C can cause more intense symptoms, such as kidney stones and severe diarrhea.
- Interactions. If you take any other regular medicines, ask your doctor if it's safe to take vitamin C. It can interact with drugs like aspirin, acetaminophen, antacids, and blood thinners. Nicotine may reduce the effects of vitamin C.
- Risks. People who are pregnant or have gout, liver disease, kidney disease, and other chronic diseases should check with a doctor before using high doses of vitamin C supplements.
