Home » How Much Vitamin C Is Too Much? The Best Answer

How Much Vitamin C Is Too Much? The Best Answer

how much vitamin c is too much

In this post, you will find the answer to can you take too much vitamin C daily. Also, how much vitamin C is too much? Plus, learn topics related to excess vitamin C as follows. Click the link below to go straight to a specific section.

Table of Contents

Vitamin C is a water-soluble vitamin taken from the metabolism of glucose.

It is also known as ascorbic acid that plays a crucial role in many health improvement related issues, for example,

  • Protecting the immune system
  • Reducing the intensity of our bodies’ allergic responses
  • Helping your body to fight back infections
  • Enhances iron absorption
  • Neutralizes free radicals and toxins

But, vitamin C deficiency can lead to serious health problems such as:

  • Impaired immunity
  • Higher vulnerability to infections
  • Fatal disease scurvy

Now, given the above facts, is too much vitamin C bad? or can you get sick from too much vitamin C? Let’s find the answers.

Can You Have Too Much Vitamin C?

Taking too much vitamin C seems unlikely to hurt you. But taking too much vitamin C in one day may give you a headache or cause nausea and diarrhea.

Also, excess vitamin C may cause vomiting and heartburn. Plus, other likely symptoms of too much vitamin C are insomnia and abdominal cramps.

What are the benefits of high-dose vitamin C?

Benefits of taking high dose vitamin C supplements

Vitamin C is well-known for its essential antioxidant effects in the human body. That is to say, it protects your body’s cells and tissues from oxidative damages.

But, the level of Vit C during an infection can be drained and you have to increase the turnover of it in your body by daily high dosage intake of C.

Some clinical studies demonstrate that taking a high amount of C can reduce systemic, cerebral, and myocardial ischemia/reperfusion injury.

On the other side, there are laboratory studies that say taking Vit C in a big dose may help fight cancer cells.

Two studies on the effects of high-dose ascorbic acid in patients with cancer show that it improves the quality of those lives.

what happens if you take too much vitamin c?

Too much vitamin c may cause digestive symptoms. Plus, vit C overdose may result in accumulation of iron in your body that is called iron overload or hemochromatosis. That is, it can threaten your health. To illustrate, iron overload can lead to:

  • Joint pain
  • Irregular heart rhythm
  • Fatigue
  • Abdominal pain
  • Liver disease 
  • Diabetes mellitus
  • Heart attack 

Also, Taking high doses of vitamin C supplements may result in kidney stones by increasing oxalate in the urine.

How Much Vitamin C Is Too Much?

In brief, the upper limit is 2,000 milligram (mg) a day, that is considered as a mega dose.

To put it another way, choose a supplement that gives vitamin C not more than 100% of daily needs.

Recommended Dose of Vitamin C

vitamin c dosage for adults

The U.S. Food and Nutrition Board recommends a 45 mg day dietary allowance of vitamin C for adults.

Dietary recommendations by the U.S. Institute of Medicine for vitamin C dosage for adults are 75 to 90 mg per day for both men and women. But during pregnancy, that RDA can increase to 85-120 mg a day.

On the other hand, the upper limit is 2000 mg per day. That is the highest possible intake for adults to avoid any health risks.

Too Much Vitamin C Symptoms

too much vitamin c symptoms

Possible side effects of too much vitamin C on your body are known as vitamin C overdose symptoms, such as:

  • Diarrhea
  • Fatigue: that means too much vitamin C may make you tired
  • Gastritis
  • Nausea
  • Heartburn
  • insomnia
  • Flushing
  • Headache

Daily intake of more than 1,000 mg vitamin C is not allowed in people with chronic health issues such as kidney diseases, liver disorders.


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