Vitamin C has been praised as a cold-fighting, immune-boosting, health miracle. But is it possible to get too much of a good thing?
The Need for Vitamin C
Vitamin C, also known as ascorbic acid, is an essential nutrient that helps grow and repair tissue and bone. It also helps prevent diseases such as scurvy, which can be caused by a vitamin C deficiency.
The body requires vitamin C to help absorb iron, another essential nutrient. vitamin C improves cardiovascular health and aids in fighting diseases like cancer and asthma.
Many supplement companies and health experts praise vitamin C for fighting the common cold. Over-the-counter cold remedies like throat lozenges and cough syrups often are enhanced with vitamin C to help stave off and combat colds. However, it's inconclusive whether vitamin C can benefit the immune health of most people.
How Much Vitamin C?
For most people, vitamin C deficiency isn't an issue. A healthy diet rich in fruits and vegetables should provide all of the dietary vitamin C necessary to prevent scurvy, repair tissue and bone, and absorb iron. However, vitamin C intake may need to be supplemented for certain diets and populations.
The National Institutes of Health's Office of Dietary Supplements lists recommendations for daily vitamin C intake for different childhood age groups:
- infants 0-6 months old -- 40 mg;
- infants 7-12 months old -- 50 mg;
- toddlers 1-3 years old -- 15 mg;
- children 4-8 years old -- 25 mg;
- children 9-13 years old -- 45 mg;
- male teens 14-18 years old -- 75 mg; and
- female teens 14-18 years old -- 65 mg.
Men should strive to consume 90 mg of vitamin C per day, and women should aim for 75 mg. Pregnant women need a little more -- 85 mg -- for optimal health, and breastfeeding women should consume 120 mg of natural vitamin C to support their own health and their newborn infant's dietary needs.
Vitamin C Sources
Here's some food for thought. You can also get your daily dose of vitamin C through diet. Vitamin C is a naturally occurring vitamin in many fruits and vegetables. Oranges are perhaps the most well-known source of vitamin C in a fruit; a medium-sized, fresh orange contains an average of 70 mg of vitamin C, which is enough to satisfy children's and teens' daily dietary needs and nearly enough to fulfill women's dietary needs.
Other foods rich in vitamin C include:
- citrus fruits;
- melon;
- red and green peppers;
- broccoli; and
- strawberries.
Vitamin C-fortified foods, such as breads, cereal and dietary supplements are another available source. Many multivitamins contain extra vitamin C, and it is sold in pure form as a capsule or powder.
When taking vitamin C supplements, be careful not to exceed the NIH's recommended upper safe limit (an upper safe level has not been established for infants):
- toddlers 1-3 years old -- 400 mg;
- children 4-8 years old -- 650 mg;
- children 9-13 years old -- 1,200 mg;
- teens 14-18 years old -- 1,800 mg; and
- adults -- 2,000 mg.
The Dangers of Too Much Vitamin C
Like everything, moderation is key. Vitamin C is a water-soluble vitamin excreted in the urine once the body has fulfilled its need. But too much of any substance, from vitamin C to water, can be harmful to health, so doctors caution only to use vitamin C supplements in moderation.
According to the Mayo Clinic, exceeding the recommended dosage of vitamin C could cause:
- nausea;
- vomiting;
- diarrhea;
- abdominal bloating and cramps;
- heartburn;
- headache;
- kidney stones; and
- insomnia.
And that's not all. Too much vitamin C may cause the body to absorb too much iron – a condition that can lead to serious health problems. Researchers have found that excess vitamin C could interfere with the absorption and metabolism of vitamin B12, which is another essential nutrient.
With a doctor's guidance, limit vitamin C supplement intake if you take the following medications -- adverse side effects have been reported:
- acetaminophen;
- aluminum-based antacids;
- aspirin; and
- Warfarin.
A doctor can advise how to modify vitamin C intake, taking medications and diet into consideration.
Remember, the best way to ensure getting enough vitamin C in your diet without risking adverse side effects from over-saturation is to rely on natural sources. Eating fresh fruits and vegetables at every meal will not only will provide vitamin C for daily needs, but it also will help meet your other nutrient goals for a healthy lifestyle!