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How Much Vitamin C Is Safe

You Could Damage Your Major Organs

How Much Vitamin C Should I Take ? |Dr.Michael Greger

Vitamin C is known to increase iron absorption, but taking too much of it could lead to iron overload. In turn, this can cause serious damage to your heart, liver, thyroid, pancreas, and central nervous system, according to Healthline.

Iron overload is most likely to occur in individuals that have certain medical conditions, like hemochromatosis, which is a hereditary condition that increases iron absorption.

And for more, check out these 108 most popular sodas ranked by how toxic they are.

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The Bowel Tolerance Test Determines How Much Vitamin C To Take

People who have used high doses of traditional Vitamin C often experience a watery diarrhea, called a C-flush. This phenomenon happens whenever a large amount of Vitamin C is not absorbed in the small intestine. The unabsorbed Vitamin C reaches the colon where it draws water into the bowels. At the point of bowel tolerance, a watery diarrhea naturally ensues.

This is not an adverse side effect it happens because the intestines cant handle the volume of water the Vitamin C draws into the large bowel. The Vitamin C dosage that initiates a C-flush is referred to as a bowel tolerance dosage.

Daily bowel tolerance dosing to determine your current need for Vitamin C can be inconvenient and unpleasant, but a good strategy includes periodic utilization of this type of Vitamin C supplementation. Once a month, or even once a week, take spaced doses of Vitamin C powder dissolved in water until the onset of diarrhea. At this point you can determine a baseline dose, and the bowels will benefit from a healthy cleanse.

Please note: Since the liposome formulation enjoys superior absorption, it will not cause a diarrheal flush, so liposomal Vitamin C is not appropriate for this test.

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Fruits And Vegetables With High Levels Of Vitamin C

There are many fruits and vegetables that have high levels of Vitamin C. If youre worried about taking supplements and the side effects, eating fruit ensures you get your daily dose of Vitamin C without the problems.

Guava has 377 milligrams of Vitamin C. Kiwis have 167 mg.

Bell peppers have 190 milligrams per cup and only 46 calories. Berries like blueberries, blackberries, raspberries, and strawberries all contain Vitamin C. Strawberries contain the highest amount at 98 mg per cup.

Surprisingly, oranges, often synonymous with high amounts of Vitamin C have only 96 mg per cup. Clementines, lemons, and grapefruits are also good sources of Vitamin C but contain fewer milligrams than oranges.

Broccoli, cabbage, and Brussel sprouts are also good sources of Vitamin C. Kale is also a good source with 53 mg per cooked cup.

With so many choices, its easy to start your day with a healthy breakfast that contains enough Vitamin C to keep you healthy.

Excessive Intake Of Vitamin C Can Produce Negative Interactions

How Much Vitamin C Is Safe During Pregnancy?

Taking a Vitamin C supplement in a higher dosage than whats recommended can have adverse interactions, especially if youre on certain medications.

Some medicines contain aluminum such as phosphate binders. Taking more than 2,000 mg in supplement form can increase your absorption of aluminum. This can be harmful to people suffering from kidney problems.

If youre taking an oral contraceptive or are on a hormone replacement therapy, taking an excess of Vitamin C in supplement form may increase your estrogen levels.

Talk to your doctor if youre on chemotherapy. Using antioxidants like Vitamin C while undergoing chemotherapy may reduce the drugs effects. However, speak with your physician first as there is a difference in opinion on antioxidants and its effects on chemotherapy.

Taking Vitamin C orally in supplement form may reduce the effects of protease inhibitors. And if youre taking Vitamin C with niacin, Warfarin, Coumadin or Jantoven, it may reduce the effects the prescribed drug is supposed to have on your body.

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How Much Does A Child Need

NIH recommends Adequate Intakes :

  • Infants 0-6 months old, 40 mg per day
  • Infants 7-12 months old, 50 mg per day.

The RDAs of vitamin C for teens and children are:

  • Toddlers 1-3 years old, 15 mg per day
  • Children 4-8 years old, 25 mg per day
  • Children 9-13 years old, 45 mg per day
  • Male teens 14-18 years old, 75 mg per day
  • Female teens 14-18 years old, 65 mg per day

The Health Benefits Of Vitamin C

An important antioxidant, vitamin C supports the immune system and has been shown to not only shorten the duration of the common cold but help reduce the severity of colds. It has also been shown to fight oxidative stress and support the cardiovascular system, especially the heart.

Vitamin C has even been linked to longevity, and who doesn’t want to live a longer, healthier life? But wait, there’s even more. Vitamin C plays a vital role in collagen synthesis, which means smoother, healthier-looking skin.

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The Recommended Dietary Allowance

The recommended dietary allowance for vitamin C is based on the amount of vitamin C intake necessary to maintain neutrophil vitamin C concentration with minimal urinary excretion of vitamin C and is proposed to provide sufficient antioxidant protection . The recommended intake for smokers is 35 mg/day higher than for nonsmokers, because smokers are under increased oxidative stress from the toxins in cigarette smoke and generally have lower blood concentrations of vitamin C .

Table 2. Recommended Dietary Allowance for Vitamin C

Life Stage

Negative Vitamin C Side Effects

How Much Vitamin C Do You Need?

The recommended daily allowance of vitamin C for adults is between 75 to 90 milligrams per day depending on someones age, while the safe upper limit is 2,000 milligrams a day, according according to the National Institutes of Health . This means that a general recommendation is to take no more than 2,000 milligrams per day of vitamin C, especially for weeks or months on end. Pregnant women need about 85 milligrams per day of vitamin C, while breastfeeding women require about 120 mg/day.

Is 1,000 mg of vitamin C too much? While the NIH recommends no more than 2,000 mg/day, according to the Linus Pauling Institute, There is no reliable scientific evidence that doses of vitamin C up to 10 g/day in adults are toxic or detrimental to health. That said, you can only absorb so much vitamin C at one time, which means smaller doses are both safer and more effective.

If too much of this vitamin accumulates in the body, vitamin C side effects can possibly include:

  • Digestive issues like diarrhea, nausea or abdominal cramps
  • Heartburn
  • Accumulation of iron, which can damage tissue and cause problems with the kidneys
  • In rare instances, development kidney stones, increased oxidative stress and excess iron absorption

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Taking Supplements In High Doses May Lead To Kidney Stones

Excess vitamin C is excreted from the body as oxalate, a bodily waste product.

Oxalate typically exits the body via urine. However, under some circumstances, oxalate may bind to minerals and form crystals that can lead to the formation of kidney stones .

Consuming too much vitamin C has the potential to increase the amount of oxalate in your urine, thus increasing the risk of developing kidney stones .

In one study that had adults take a 1,000-mg vitamin C supplement twice daily for 6 days, the amount of oxalate they excreted increased by 20% .

High vitamin C intake is not only associated with greater amounts of urinary oxalate but also linked to the development of kidney stones, especially if you consume amounts greater than 2,000 mg (


Consuming too much vitamin C may increase the amount of oxalate in your kidneys, which has the potential to lead to kidney stones.

Can Vitamin C Fight A Cold

A small amount ofresearch from the 1970s suggestedvitamin C was the answer to preventing and treating the common cold. For decades this has fueled the old wives tale that vitamin C boosts the immune system and can prevent illnesses such as cold and flu. Continuing research has indicated that this isnt quite the case. Whilesome datasuggests that extra vitamin C may help those who partake in extreme exercise or are active in cold environments, its not the magic pill people many folks make it out to be. If you are falling short of your daily needs for vitamin C you will potentially see better immune function when that deficiency is corrected. A study from 2017 determined that meeting needs for vitamin C would be enough to help prevent some infections from occurring while higher doses are needed to fight inflammation from existing infections.

The research is more compelling on how the antioxidant powder of vitamin C can fight inflammation and possibly shorten the duration of an illness when taken at the onset of symptoms. Newly publishedresearchcontinues to explore the antioxidant powder of vitamin c and both athletes and non-athletes. More importantly, this doesnt translate to more is better. Thereissuch thing as too much vitamin C.

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Signs And Symptoms Of Too Much

Taking very large doses of vitamin C has been shown to cause an overdose in this vitamin, also referred to as vitamin C toxicity. Some symptoms of vitamin C overdose can include:

  • Digestive issues like diarrhea, nausea or abdominal cramps
  • Heartburn
  • Atherosclerosis
  • Rebound scurvy

Levels of vitamin C in the blood are controlled by the kidneys. One of the biggest concerns with vitamin C overdose is the risk for kidney stone formation, so vitamin C supplements are not usually recommended for men and others at risk for oxalate stones.

Very high doses can acidify the urine, cause digestive issues and interfere with antioxidant balance in the body. Among people who have the conditions thalassemia or hemochromatosis, too much vitamin C can cause iron overload.

What effects can taking too much vitamin C during pregnancy have?

Pregnant women need about 85 milligrams per day of vitamin C, while breastfeeding women require about 120 mg/day. Too much vitamin C during pregnancy can lead to diarrhea, nausea and possibly dehydration, which can pose a risk to the baby.

Its possible these effects can impact levels of amniotic fluid, especially if vomiting and severe dehydration occur over long periods of time.

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Stay Healthy With A Good Health Insurance Plan

1 How much vitamin C is in fresh squeezed orange juice ...

Part of staying healthy is not taking too much Vitamin C or other supplements that can have adverse effects on your body and health. Another part of staying healthy is seeing your doctor regularly.

Having good health insurance ensures that you can keep your health in check all year round. And that starts by picking a good medical network.

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What Are The Preferred Sources Of Vitamin C

There is no reason to take vitamin supplements if you eat a healthy whole food plant-based diet. Vegetables and fruits are good sources of vitamin C. You can see analytically the list with the richest foods in vitamin C here. For instance, kale, broccoli, or peppers are particularly high in vitamin C.

In Conclusion Is 1000 Mg Of Vitamin C Safe

In general, the daily consumption of 1,000 mg of vitamin C is pretty safe. There are no side effects for most people. Certainly, people on medication should consult their health care provider, before taking any supplement.

Its a good idea to boost vitamin C intake, especially in the winter, as vitamin C seems to be beneficial against the flu and common cold. It may boost the immune system.

Moreover, we should take at least 1,000 mg of vitamin C during the summer, as well. Vitamin C naturally boosts collagen production, protecting us from skin aging and reliving us from sunburns! Also, it helps us burn body fat and lose weight!

Certainly, eating foods high in vitamin C is the best way to boost your daily intake. Furthermore, taking a 1,000 mg tablet wont do any harm. Moreover, vitamin C supplements are pretty cheap. You can compare prices on Amazon.

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Whats The Recommended Intake

The Institute of Medicine has developed a set of reference values for specific nutrient intake levels, including for vitamin C.

One set of guidelines is known as the Recommended Dietary Allowance and considers average daily nutrient intake from both foods and supplements.

RDA recommendations for specific gender and age groups should meet the nutrient needs of 9798% of healthy individuals (

Here are the RDAs for vitamin C :

Life stage
Adult women 75 mg
Adult men 90 mg
Pregnant women 85 mg
Breastfeeding women 120 mg

In addition to the RDA recommendations for vitamin C, the Food and Drug Administration has issued a recommended Daily Value .

The DV was developed for food and supplement labels. It helps you determine the percentage of nutrients in a single serving of food, compared with the daily requirements. On food labels, this is displayed as %DV .

Currently, the recommended DV for vitamin C for adults and children aged 4 and above is 60 mg regardless of gender. However, in January 2020, this will increase to 90 mg .


The RDA for Vitamin C ranges from 1575 mg for children, 75 mg for adult women, 90 mg for adult men, and 85120 mg for women who are pregnant or breastfeeding.

Vitamin C is essential for overall health and wellness, and the nutrient may particularly benefit certain conditions.

The vitamin is especially helpful for immune health, as it supports your immune systems cellular function .

Vitamin C Side Effects & How To Prevent Adverse Reactions

Vitamin C and your health

By Jillian Levy, CHHC

Many studies have found that people who eat diets high vitamin C foods have better protection against diseases like cancer, vision loss and obesity, along with other positive vitamin C side effects. Also known as ascorbic acid, this water-soluble vitamin acts as an antioxidant. It helps reduce free radical damage and inflammation that can lead to many health problems.

Vitamin C is obtained from eating lots of different fruits and vegetables such as citrus fruits like oranges, kiwi, berries and leafy greens plus many people get additional vitamin C from supplements. Your body cant make its own vitamin C, and its important to get an ongoing supply from your diet, since it is flushed out of your body regularly via urine. But can too much vitamin C have side effects?

While it doesnt happen very often, high doses of vitamin C taken in supplement form can cause vitamin C toxicity, which is characterized by a number of adverse reactions. Potential negative vitamin C side effects can include digestive issues like diarrhea, nausea or abdominal cramps, along with insomnia, excess iron absorption and possibly kidney stones.

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Too Much Vitamin C When Breastfeeding

The upper limit for vitamin C is 2,000 milligrams per day. With most of your supply coming from your diet, its unlikely you will have too much. However, if you decided to take supplements in high doses, then you could.

As far as youre concerned, too much vitamin C can cause diarrhea, vomiting, heartburn, stomach cramps, and headaches .

When it comes to the effects on your baby, it is thought too much vitamin C during pregnancy can cause scurvy in a newborn. This is because the liver processes it too quickly, eliminating it from the body. Likewise, not enough can also adversely affect the health of your unborn baby.

We have, however, already mentioned that our body regulates how much vitamin C is passed to the baby in milk when breastfeeding.

If you plan to take higher than recommended doses of vitamin C for any reason, discuss it with your health professional first.

How Much Vitamin C Should I Take

May 3, 2019 | Vitamin C, Vitamins and Nutrients

Vitamin C has no known toxicity. That means you wont get Vitamin C poisoning. But, depending on the type of Vitamin C you take, you may have a different answer for the how much Vitamin C should I take? question. Your body has two primary mechanisms for helping determine your need for Vitamin C. Although far from perfect, these mechanisms are a good starting point to figure out how much Vitamin C you should take.

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Heart Disease And Cancer

Vitamin C is often erroneously lauded for its ability to fight heart disease and cancer. Much of the misperception has been fueled by vitamin C’s antioxidant properties.

While antioxidants seem to reduce the oxidative stress associated with these diseases, there is little to no evidence that vitamin C supplements can directly influence the risk.

Among the clinical findings:

  • A 10-year study involving 14,641 men over the age of 50 showed that a 500-mg dose of vitamin C did nothing to alter the rate of heart attacks or stroke compared to a placebo.
  • A nine-year study involving 8,171 older women demonstrated that 500 milligrams of vitamin C have no impact on the rate of cancer compared to the general population.
  • A 5-year study involving 77,721 older men and women also showed no association between vitamin C intake and the risk of lung cancer.


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