Vitamin C is commonly found in many fruits and vegetables. It is a water-soluble vitamin with a great impact on the human’s body. Vitamin C boosts the immune system, has great antioxidant properties, takes part in the process of collagen production, helps the absorption of iron in the gastrointestinal system, etc. The only problem with vitamin C is that the human body does not produce it or store it. For this reason, vitamin C should be taken daily through diet, and if needed through supplements. However, on the other hand, overdose of vitamin C can be toxic.

What Counts as Vitamin C Overdose?

The maximum amount of vitamin C recommended for an adult should not exceed 2,000 mg a day. However, as everyone is unique, it is very important to discuss your nutritional needs with a professional healthcare provider.

The upper limits of vitamin C based on a person’s age are as follows:

Recommended Daily Intake of Vitamin C

The amount of vitamin C a person needs daily depends on age. Normally, as a baby or a child, a person needs less vitamin C, compared to the time during adolescence or adulthood. On average, the daily recommended doses of vitamin C based on specific ages can be found in the following table:

If you are a smoker, make sure to add another 35 mg of vitamin C a day.

What Happen If You Take Too Much Vitamin C?

Taking more vitamin C than recommended is not a life-threatening situation. However, various signs and symptoms may appear, such as:

1. Gastrointestinal Problems

An upset stomach, together with abdominal cramps, diarrhea, heartburn, nausea, and vomiting, are common signs of vitamin C overdose. Other possible gastrointestinal problems include excessive flatulence, abdominal bloating, indigestion, tender abdominal mass on the left side of the abdomen, etc. All these signs and symptoms tend to get better once the vitamin C consumption in higher doses than normal is stopped.

2. Oral and Facial Problems

A formation of mouth ulcers and sores is common in overdose of vitamin C. In the face, an eruption of skin rash is possible, often accompanied with facial flushing and itchiness. Dental problems are also possible, mostly cavity problems or even a tooth decay.

3. Pain

An overdose of vitamin C can lead to leg and foot cramps, severe back pain muscle pain or headaches.

4. Anemia

Hemolytic anemia is common in a vitamin C overdose. This type of anemia is more common among those who have a genetic enzyme deficiency where the red blood cells are damaged, leading to anemia. Fatigue, weakness and other signs and symptoms of anemia are present.

The overdose can also lead to a vitamin B12 deficiency anemia. Copper deficiency is also possible due to excessive amounts of vitamin C taken daily with food or with supplement pills.

5. Kidney Stones

Various kidney problems, especially kidney stones are possible. In cases of an excessive presence of vitamin C in the body, calcium oxalate will be deposited and collected in the kidneys, leading to a formation of kidney stones. If you know that you have a kidney stone, you should not take more than 100 mg of vitamin C a day.

6. Iron toxicity

Vitamin C normally helps the absorption of iron in the gastrointestinal system. In cases of vitamin C overdose, more iron will be absorbed, often leading to iron toxicity. In such cases, problems with normal liver function or various heart diseases can develop.

7. Sleep Problems

Poor sleep or even insomnia is common during an overdose of vitamin C. Increased stress is also possible, which will only aggravate the sleeping problems.

8. Cataracts

The overdose increases the risk of cataracts, as a long-term and low-dose supplementation with vitamin C prevents it.

9. Drug Interaction

When vitamin C daily intake is higher than recommended, certain drug interactions are possible as well, such as with Tylenol where there is an increased risk of liver damage. An interaction with tests for blood sugar and cholesterol are also possible, as well as, with the test of blood in the stool.

How to Eat Vitamin Safely

Vitamin C supplements are widely available as 500 mg or 1,000 mg pills. Many prefer to take these pills daily for various reasons.

However, you should know that your daily vitamin C needs can be easily achieved with eating fresh fruits and vegetables. You should try to consume more of foods rich in vitamin C than taking vitamin C supplements.

Good sources of vitamin C are citrus fruits such as lemon and orange, but vegetables such as cauliflower or pepper are rich in vitamin C too. If you want to get all the nutrients from a certain food, don’t cook it for too long or at a high temperature. If possible eat raw vegetables as they are healthier.

In the following table, you can find the amount of vitamin C commonly found in a certain food. However, you should keep in mind that the amount of vitamin C in a certain food greatly varies based on their time of picking, growing conditions, climate, and many other factors.