Vitamin C is an essential vitamin for the human body. Works as an antioxidant, blood pressure control, anti-inflammatory and collagen regeneration. Vitamin C is generally safe to take even in high doses. However, some people may sometimes experience mild side effects, such as gastrointestinal upset symptoms, rarely having serious side effects. This article gives recommendations on vitamin C dosage, possible side effects of overuse, and other warnings.

Regularly eating foods rich in vitamin C will not lead to any health problems. However, taking too much vitamin C orally can cause side effects.

In adults, the recommended dietary allowance (RDA) of vitamin C is 90 mg for men and 75 mg for women.

When a person takes more than the limit of vitamin C that the body needs, there may be mild digestive disorders due to the amount of vitamin C that the body does not absorb, stimulating the digestive tract.

Common mild side effects of too much vitamin C include:

diarrhea, nausea
stomach cramps
stomach discomfort, flatulence

The body does not absorb all of the vitamin C it gets from supplements. If a person takes 30 180 mg of vitamin C per day, their body will absorb about 70% to 90% of this vitamin. If a person takes more than 1 gram (g) of vitamin C per day, the body will absorb 50% less of the vitamin, helping to reduce the risk of negative side effects. The remaining amount of vitamin C will be excreted in the urine.

How much vitamin C is too much?

Since vitamin C can cause unpleasant symptoms if taken in excess, the Food and Nutrition Council has set a “maximum limit for the body to accept”.
According to experts, the upper limit for vitamin C intake in people 19 and older is 2,000 mg for men and women. Limits remain for pregnant or lactating women.

The above daily vitamin C levels for children and infants are as follows:

400 mg for infants 1 year to 3 years.
650 mg for children 4 years to 8 years
1,200 mg for children 9 years to 13 years
1,800 mg for adolescents aged 14 to 18 years

There are exceptions to these limits, but this only applies with the advice of a doctor. Some people may need to take larger amounts of vitamin C for medical treatment.

Serious side effects

Less common, some possible health risks from taking too much vitamin C include:

Kidney stones: too much vitamin C can cause a person to excrete oxalate and uric acid compounds in the urine. These compounds can lead to the formation of kidney stones.
Nutritional imbalances: Excess vitamin C intake can impair the body’s ability to process other nutrients. For example, vitamin C can decrease vitamin B-12 and copper levels in the body. The presence of vitamin C can also enhance iron absorption in the body, which can lead to excessive levels.
Spinal spines: According to the Arthritis Foundation, a study found that the presence of very high levels of vitamin C in the body increases the likelihood of spinal spines. However, the Foundation also cites a study showing that people with low vitamin C intake have an increased risk of rheumatoid arthritis, an inflammatory arthritis condition.
Reduces the effectiveness of niacin-simvastatin (a medication for lipid disorders): Evidence suggests that vitamin C supplementation may decrease the body’s ability to increase high-density lipoprotein (HDL) cholesterol levels in users. combination drug niacin-simvastatin.

If a person is taking vitamin C and niacin-simvastatin at the same time, talk to their doctor about the most appropriate option.

How much vitamin C should I take?

A person’s body cannot make vitamin C, so people need to eat enough foods containing vitamin C to meet their daily needs. If someone is at risk of vitamin C deficiency, you can take vitamin C orally

Recommended amount of vitamin C (unit: mg)

Age Male Female
1-3 15 15
4-8 25 25
9-13 45 45
14-18 75 65
19+ 90 75

Smokers should take 35 mg more vitamin C per day than nonsmokers.

During pregnancy or breastfeeding, women should take the following amounts of vitamin C each day:

14-18 years: 80 mg during pregnancy and 115 mg while breastfeeding
19 years and older: 85 mg during pregnancy and 120 mg while breastfeeding.

There are currently no studies on vitamin C intake in children younger than 1 year. Therefore, experts give estimates that are likely enough:

40 mg for children aged 0 to 6 months
50 mg for children 7 to 12 months.