Can You Overdose On Vitamin C? Symptoms & How To Handle It In 2024

You’re not alone if you’re trying to decrease your odds of getting sick. The past few years have shifted how many of us view and value our health. While we’re trying to eat healthier, move a little more, and sleep better, we might also incorporate dietary supplements to help support immune function. Enter vitamin C supplementation.

Vitamin C, also called ascorbic acid,^[1] is one of the best-known and most accessible antioxidants that can help support immunity and keep you from calling in sick. It’s a water-soluble vitamin that plays a critical role in many body functions, and it’s found abundantly in vegetables and many fruits–like citrus fruits. Still, many people take a daily vitamin C supplement to ensure they get enough of it. But can you overdose on vitamin C? 

This article will examine the effects of excess vitamin C and review what to do if you experience overdose symptoms.  

How Much Vitamin C Is Too Much?

Taking vitamin C supplements has become a standard part of many health routines. But to know how much vitamin C is too much, we must first understand our daily needs. According to the research presented by the National Institutes of Health,^[1] the average adult male needs 90 milligrams of vitamin C daily. Adult women need 75 milligrams daily unless they are pregnant or breastfeeding. Breastfeeding women have an increased demand for this essential vitamin and need approximately 120 milligrams daily.

Of course, discussing your needs with your doctor is essential. However, the upper limit, or maximum recommended amount, is 2,000 milligrams per day, including all supplemental vitamin C sources. 

Vitamin C Overdose Symptoms

Vitamin C is water-soluble, meaning your body absorbs what it needs and excretes the rest. We do not store excessive amounts of water-soluble vitamins like fat-soluble ones. And since the human body cannot produce or store vitamin C, we must consume it in our diet. 

Usually, even at high doses, vitamin C is not known to be harmful or cause adverse effects.

However, if you take too much vitamin C at once, your body may have difficulty processing it, and you may experience unwanted symptoms. For example, too much vitamin C may lead to digestive issues like diarrhea or nausea. Some people also report acid reflux, but little evidence supports this claim.

High levels of vitamin C may also contribute to nutrient imbalances, such as iron overload. Vitamin C is known to help enhance iron absorption in the body. It can bind with non-heme iron, found in plant sources, supporting your body’s ability to absorb the mineral.^[2] 

Individuals living with conditions that increase the potential for iron accumulation in the body should use vitamin C supplements cautiously. Iron overload can cause severe heart, pancreas, liver, thyroid, and central nervous system issues. Taking vitamin C may also reduce the amount of other nutrients in the body, like vitamin B12.

Vitamin C Exacerbates Certain Medical Conditions

Additionally, excessive vitamin C may also lead to kidney stones^[3] in men. Our bodies typically excrete excess vitamin C as waste products in the form of oxalate and uric acid. However, in some cases, oxalate may bind to minerals in the body and form crystals that ultimately lead to the formation of kidney stones. 

Consuming more vitamin C than the body needs may also increase a person’s likelihood of developing bone spurs or worsening osteoarthritis.^[4] However, more research is still needed regarding ascorbic acid and its role in bone health.

Lastly, excessive dietary vitamin C intake may interfere with certain medications and over-the-counter drugs. For example, evidence suggests that vitamin C supplementation may interfere with niacin and statins,^[1] like niacin-simvastatin.  

Possible Side Effects

Can too much vitamin C hurt you? Unfortunately, excess amounts of vitamin C may lead to some negative effects. Vitamin C toxicity may cause:

• Abdominal pain.
• Abdominal cramps.
• Headaches.
• Diarrhea.
• Nausea.
• Sleeping issues.

How To Handle Vitamin C Overdose

So, what happens if you overdose on vitamin C? Step one: don’t panic. Our bodies excrete excess amounts of water-soluble vitamins through our urine. In most cases regarding excessive vitamin C intake, simply allowing your body to excrete the excess is enough to address overdose symptoms. 

Drinking more water may also help flush out excess ascorbic acid from your system. But, of course, be mindful of your water intake, as too much water may cause imbalances in other vital nutrients. 

Most importantly, if you exceed the recommended upper limit, consider meeting with trusted health professionals to ensure your action plan best addresses your medical needs based on your medical history. 

Final Thought

Many people rely on ascorbic acid in supplement form to ensure they get enough vitamin C to support their immune system. You’re not alone if you’re wondering, “Can I overdose on vitamin C?” While vitamin C is crucial in keeping our bodies healthy, excess vitamin C side effects can take a toll.

While it’s difficult to overdose on vitamins like ascorbic acid, overconsumption may contribute to the formation of kidney stones, worsening osteoarthritis, gastrointestinal distress, abdominal pain, and other issues. If you experience vitamin C toxicity or overdose concerns, stop taking supplements that contain vitamin C and contact your doctor. 

Of course, vitamin C deficiency presents its concerns. So a supplement regimen designed according to your individualized needs may offer potential health benefits. Your doctor or registered dietitian nutritionist can help you understand your vitamin C deficiency and your needs to ensure you get enough vitamin C daily.

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