Can You Take Too Much Vitamin C?
We get it: You want to protect your body from disease, and chugging a ton of orange juice or Emergen-C seems like a tasty and easy way to do it. But can you consume too much vitamin C? The short answer is “yes.”
Here’s what you need to know:
What Is Vitamin C and Where Is It Found?
Vitamin C, also known as ascorbic acid, is an essential nutrient.
Common food sources of vitamin C are citrus fruits, broccoli, kale, sweet potatoes, tomatoes, kiwifruit, cantaloupe, papaya, and peppers.
It’s also often sold as a dietary supplement in pill or tablet forms. Some vitamin C supplements are marketed as immune system-supporting, like Emergen-C and Airborne.
Related: Does Emergen-C Really Work?
Vitamin C Benefits
When consumed in appropriate amounts, vitamin C:
Supports a healthy immune system. Vitamin C is known as an immune-boosting superstar because it encourages white blood cell production and helps these blood cells function more effectively by protecting them against harmful molecules. So why is this so important? White blood cells are essential in protecting your body against infection.
Helps prevent iron deficiency. Vitamin C can help your body more effectively absorb iron, which is essential for transporting oxygen throughout the body. This benefit is especially important for people who don’t eat meat or who are prone to anemia.
Can reduce your risk of heart disease. Heart disease, the leading cause of death in the U.S., is often caused by high blood pressure and/or high cholesterol. Studies have shown that adequate vitamin C consumption may be helpful in reducing those risk factors, thereby reducing your risk of heart disease.
How Much Vitamin C Do You Need?
Most adults should consume 65 to 90 milligrams (mg) of vitamin C per day, according to the Mayo Clinic. You can meet this daily quota with about two oranges. The Office of Dietary Supplements says the upper limit for vitamin C intake is about 2,000 mg for men and women over 19 years old. It would be hard to reach this amount with food alone, but you may accidentally take too much if you rely on supplements for your vitamin C needs—especially chewables or effervescent tablets that taste good.
Related: 10 Vitamin C-Packed Recipes
Too Much Vitamin C Side Effects
While taking megadoses of vitamin C is unlikely to be harmful in the long run, it can cause some pretty unpleasant side effects. Common side effects of too much vitamin C include:
Diarrhea
Vomiting
Bloating
Heartburn
Headache
Insomnia
While these issues are generally more uncomfortable than harmful, more severe side effects can occur. For instance, taking too much vitamin C can cause your body to produce too much iron. This can lead to serious damage to your heart, central nervous system, and liver. This damage is unlikely unless you have a condition that affects iron absorption, however.
Overconsumption of vitamin C can also cause kidney stones. Excess vitamin C is excreted via urine as a waste product known as oxalate, which can bind to minerals and form stones.
