Vitamin C: Why is it important?

Vitamin C is a vital nutrient for health. Vitamin C benefits include helping form and maintain bones, cartilage, skin, and blood vessels. As an antioxidant, it also supports the immune system.
Fruits and vegetables are the best sources, but some people may need supplements.
Vitamin C occurs naturally in some foods, especially fruits and vegetables. Vitamin C supplements are also available.
Other names for vitamin C include L-ascorbic acid, ascorbic acid, and L-ascorbate.
In this article, learn more about why we need vitamin C, how much we need, and where to find it.
Vitamin C is water soluble, and the body does not store it. To maintain adequate levels of vitamin C, people need to consume food that contains it every day.
The body needs vitamin C for various functions. Here are some of them:
ROS are substances such as free radicals that result from natural bodily processes, exposure to pollution, and other factors. They can lead to oxidative stress, which can, in turn, cause cell damage.
Vitamin C’s antioxidant activity may help reduce inflammation and lower the risk of developing various conditions, including some cancers.
The body needs vitamin C to produce collagen. This is the main component of connective tissue and makes up 1–2% of muscle tissue.
Collagen is a vital component in fibrous tissues such as:
Low levels of vitamin C in the body can lead to scurvy. Symptoms of scurvy include swollen joints, bleeding gums and loose teeth, anemia, and tiredness.
Vitamin C plays a role in many body functions. The immune system is a key one, mainly due to vitamin C’s antioxidant properties.
Antioxidants protect the body from oxidative stress. This is a process that, over time, can cause damage to most organs and tissues in the body. Antioxidants are also known to help support the natural abilities of your immune system.
Although vitamin C is a known antioxidant and has benefits for the immune system, there’s some question over its ability to treat active infections. People often use it as a supplement in the winter months to fight colds, and some even use it as a treatment for COVID-19. However, scientists are yet to prove the true value of these uses.
There is also little scientific data to prove the benefits of vitamin C for chronic conditions that sometimes benefit from antioxidant therapies, such as cancer and cardiovascular disease.
The only condition that vitamin C is proven to help treat is scurvy. Scurvy causes weakness, slow wound healing, bruising, and other symptoms. It’s due to a severe lack of vitamin C in your diet.
In addition to its role as an antioxidant, vitamin C also helps produce or process:
Your body controls the amount of vitamin C in your body very carefully. It’s present in small amounts in most cells. Unlike other forms of vitamins, vitamin C is usually present in higher amounts in cells than in plasma, which is the fluid part of your blood.
Daily vitamin C intake is recommended at every age, but this doesn’t necessarily mean that you need to take supplements.
How much vitamin C you need every day depends on your age and how much you take in through your diet. According to the National Institutes of Health, your body will absorb 70–90% of the vitamin C you consume if you take in a moderate amount. The NIH considers 30–180 milligrams (mg) per day to be a moderate amount.
If you take in more than 1 gram of vitamin C in a day, your body will absorb less than half of it and get rid of the rest in your urine.
This makes it important to know how much you need for your age each day to avoid taking supplements that your body wouldn’t absorb anyway. By age, vitamin C intake recommendations — per the NIH — are:
In general, males need higher amounts within these ranges, and those who are pregnant or breastfeeding need more vitamin C as well.
Talk with your healthcare team or obstetrician before taking any supplements while pregnant or breastfeeding.
If you smoke, your vitamin C requirements are also higher. The NIH recommends an additional 35 mg per day of vitamin C for people who smoke cigarettes.
Most vitamins are suitable to take at any time of the day, but you may want to check with your doctor before starting any supplements.
Certain vitamins and minerals, including vitamin C, can interact with some prescription medications. If you choose to take a vitamin C supplement, you may need to coordinate the timing of the supplement with the timing of any other medications you take.
Examples of medications that could interact with vitamin C include:
Some foods high in vitamin C include:
Other foods contain vitamin C added during the manufacturing process, such as certain varieties of milk and cereals.
Depending on how much of these foods you eat, you may get enough vitamin C in your diet without realizing it. For example, a single orange contains about 83 mg of vitamin C, and a cup of sliced strawberries contains about 98 mg.
Too little vitamin C can cause symptoms of deficiency, including:
Scurvy is the most severe form of vitamin C deficiency, and it can be fatal without treatment.
If you get more vitamin C than you need, your body will usually get rid of it through your urine. However, excessively high amounts can also be dangerous.
Some symptoms that indicate you’re taking in too much vitamin C include:
Vitamin C plays an important role in many processes in our bodies. Many people get enough vitamin C from their diet alone, but supplements can help those whose diets are lacking certain types of foods.
Some people may take supplements as a way to help treat certain conditions, but evidence that vitamin C can help fight a cold or treat chronic conditions is lacking.
Talk with your healthcare team before starting any nutrition supplements if you take prescription medications or have a chronic condition. Some supplements can interact with medications or cause complications for certain therapies.