Whether you're looking to improve your overall health or boost your immune system, vitamin C is one of the most important nutrients you need to stay healthy and it's a go-to for many people when they think they are getting sick. People have sworn by it for ages (whether in food or supplements) and for good reason. Health experts, nutritionists and science all agree that not only is it a vital nutrient but it can help prevent infections and help you get better when you are already sick.

Vitamin C is an important antioxidant for immune health. It works by helping your body heal from and fight off infections, and can help keep you from getting sick and support you when you are sick. But did you know your body needs vitamin C for a ton of other things?

Why is vitamin C important?
Vitamin C is an antioxidant that helps protect your body from harmful substances such as free radicals caused by oxidative stress, which are molecules that can damage cells. It's important to get vitamin C through supplements or food since your body can't make it on its own.

Besides its protective, healing and antioxidant effects, vitamin C is also shown to help cancer patients improve their quality of life and exhibit fewer side effects from treatment. Vitamin C is also thought to protect cardiovascular health. One study showed that people who took at least 700mg of vitamin C per day had lower risk factors for heart disease.

How to get enough vitamin C
"Typically, I recommend eating a variety of fruits and vegetables for those seeking to boost their vitamin C content," dietician Jenn Randazzo tells CNET. Vitamin C is found in many foods including:

Citrus fruits and their juices
Red and green peppers
Broccoli
Strawberries
Cantaloupe
Baked potatoes
Tomatoes
Some foods and beverages that are fortified with vitamin C
"Because vitamin C content may be reduced by prolonged storage and cooking techniques, try to consume vitamin C foods either raw or steamed for a short period of time," Randazzo adds. Another way to ensure you get enough vitamin C is to add a supplement. This can be helpful during times when you want to prevent illness, boost your immune system or get extra vitamin C support if you're sick.

"If you're worried about getting enough vitamin C into your daily diet, it is available as dietary supplements as well (usually in the form of ascorbic acid)," Randazzo says. "However, some supplements have other forms, like sodium ascorbate, calcium ascorbate, and other mineral ascorbates too. Research has not shown that any form of vitamin C is better than the others, so it's important that you use the form easiest to incorporate into your personal wellness routine."

How much vitamin C should you take?
When it comes to vitamin C, many people think more is better. The recommended daily amount is about 65-90mg per day, and the upper limit is 2,000mg per day. Most supplements on the market provide much more than 90mg, and if you're eating foods with vitamin C and supplementing, you're meeting your 90mg requirement and then some.

If you're taking more vitamin C than is recommended, it's unlikely to hurt you since the vitamin is not stored in the body. "For some, consuming too much vitamin C can cause stomach upset, like diarrhea, nausea or cramps," Randazzo says. In fact, if you are sick, your body needs much more vitamin C and your needs can increase due to inflammation and other factors. This is why it's important to talk to a health professional like a doctor or nutritionist to help you determine how much vitamin C you need to prevent or treat illness.

Vitamin C and immune health
Vitamin C plays an important role in immune health and helps your body's immune system in a few different ways. First, it supports the production of immune cells or white blood cells that you need to fight infections. Secondly, vitamin C functions as an antioxidant, which protects you from oxidative stress, which is linked to chronic health conditions and illnesses such as diabetes, heart disease and Alzheimer's.

Vitamin C and COVID-19
Vitamin C has been given to critically ill patients diagnosed with COVID-19, although there is no research to show it is effective at treating COVID-19 specifically. Studies are ongoing, but the National Institutes of Health still say there isn't enough evidence to recommend the use of vitamin C for COVID-19 patients.

It's important to remember that researchers and doctors don't have all of the answers about COVID-19 at this time. The best ways to reduce your risk of being infected with the coronavirus is to follow guidelines from the Centers for Disease Control and Prevention and World Health Organization, abide by any health orders from your local officials, and to take care of your health as much as you can overall.

Vitamin C and stress
One surprising fact about vitamin C is that it can help your body when under stress, whether that is physical or emotional. One study showed that vitamin C was helpful in reducing stress hormones in mice, which means it could help human bodies cope with the harmful effects of physical and emotional stressors.

Another 2015 study showed that vitamin C supplementation was helpful for people with anxiety. It helped mitigate the negative effects of anxiety in the body and showed promise for helping prevent future anxiety.

Given vitamin C's benefits for stress, anxiety, heart health and immunity, making sure you're getting plenty of vitamin C per day is a good step in the direction of better health.