Is Too Much Vitamin C Harmful?

Vitamin C is one of many water-soluble nutrients found naturally in fruits and vegetables. Many people also take supplements to make sure they're getting enough. This has raised concerns about the possibility of accidental overdose.

Vitamin C is a very important nutrient found in many fruits and vegetables. Getting enough of this vitamin is especially important for maintaining a healthy immune system. Interestingly, some people claim that vitamin C supplements provide benefits beyond those that can be obtained from vitamin C found in foods.
One of the most common reasons people take vitamin C supplements is the idea that they help prevent the common cold. However, many supplements contain extremely high amounts of the vitamin, which can cause unwanted side effects in some cases.

Although vitamin C (ascorbic acid) is an essential nutrient, it is possible to have too much. Vitamin C is a water-soluble vitamin that supports normal growth and development and helps your body absorb iron. Because your body does not produce or store vitamin C, it is important to include vitamin C in your diet.
For adults, the recommended daily intake of vitamin C is 65 to 90 milligrams (mg) a day and the upper limit is 2,000 mg a day. Although dietary intake of too much vitamin C is not harmful, large amounts of vitamin C supplements can cause: Diarrhea, nausea, heartburn, headaches, insomnia.
If you are experiencing digestive problems from taking too much vitamin C, simply reduce your supplement dose or avoid vitamin C supplements altogether.

Vitamin C is known to enhance iron absorption. It can bind to non-heme iron, found in plant foods. Non-heme iron is not absorbed by your body as efficiently as heme iron, the type of iron found in animal products.
Vitamin C binds to non-heme iron, making it much easier for your body to absorb. This is an important function, especially for people who get most of their iron from plant-based foods.
One study in adults showed a 67% increase in iron absorption when they supplemented with 100mg of vitamin C with a meal. However, people with conditions that increase the risk of iron accumulation in the body, such as hemoglobinopathy, should be cautious with vitamin C supplementation.
In these cases, excessive vitamin C supplementation can cause This can lead to iron overload, which can cause serious damage to your heart, liver, pancreas, thyroid, and central nervous system.
That said, iron overload is highly unlikely if you don't have increased iron absorption. Additionally, iron overload is more likely to occur when excess iron is consumed in supplement form.

Excess vitamin C will be excreted from the body as oxalate, a waste product of the body. However, in some cases, oxalates can bind with minerals and form crystals that can lead to kidney stone formation.
Consuming too much vitamin C has the potential to increase the amount of oxalate in your urine, thereby increasing your risk of developing kidney stones.
In one study that gave adults a 1,000 mg vitamin C supplement twice daily for 6 days, the amount of oxalate they excrete increased by 20%. Eating more vitamin C is not only associated with more urinary oxalate levels, but also with the development of kidney stones, especially if you consume amounts greater than 2000mg.

Since vitamin C is water soluble and your body gets rid of its excess within a few hours of you consuming it, it can be quite difficult to overdose on vitamin C.
In fact, it's nearly impossible for you to get too much vitamin C from your diet. In healthy individuals, any additional vitamin C consumed in excess of the recommended daily amount is simply eliminated from the body.
In a word, you will need to consume 29 oranges or 13 bell peppers before your intake reaches the tolerable upper limit.
However, the risk of vitamin C overdose is higher when people take supplements and may consume too much of the vitamin in some cases. For example, people with conditions that increase the risk of iron overload or are prone to kidney stones should be cautious with their vitamin C intake.
All vitamin C side effects including digestive upset and kidney stones, seem to happen when people take it in doses greater than 2,000mg
If you choose vitamin C supplements, good Ideally, you should choose one that contains no more than 100% of your daily needs. That's 90 mg per day for men and 75 mg per day for women.
If you have any questions related to the topic of nutrition for the body that need advice from a doctor, you can leave your question in the ASK VINMEC DOCTOR section directly on the hospital website. Your question will be sent to the doctor and you will receive a consultation as soon as possible!