Nutrition 101: Vitamin C

Nowadays, lots of people are seeking vitamins to boost their immunity and Vitamin C is by far the most often spoken about. To help those who have no idea where to start and whether or not they should be supplementing with Vitamin C, I’ve decided to gather some info and share my knowledge and thoughts in this Nutrition 101 series post specifically dedicated to Vitamin C.

What is Vitamin C?

Vitamin C, also known as ascorbic acid, is a water-soluble vitamin that is essential to humans as our bodies don’t produce it. You most likely know it for its often spoken about role in supporting your immune system. However, Vitamin C has numerous other important functions in the body such as aiding collagen production, wound healing and acting as an antioxidant to protect your cells from free radical damage.

Where does it come from?

Our bodies cannot synthesise Vitamin C on their own, so we must get enough of it from foods or supplements to maintain good health. One thing that is important to remember is that Vitamin C cannot be stored in the body, as a result you need to be getting sources of it in your diet each day.

Fruits and vegetables are the best sources of Vitamin C and some great options include:

  • citrus fruits
  • tomatoes
  • red and green peppers
  • kiwi
  • broccoli
  • strawberries.

Vitamin C content, however, may be reduced by prolonged storage and cooking, so if you want to minimise the amount of Vitamin C lost during food prep, a good option is to steam some of your veggies instead of cooking them. Meat, fish, poultry, eggs, and dairy products contain much smaller amounts, and cereal grains contain essentially none unless you purchase those which have been fortified with Vitamin C. 

Why is it important?

Vitamin C is essential for the growth, development, and repair of tissue all over the body, including collagen. As we age, collagen production slows and the rate of collagen loss increases- leading to joint pain, wrinkles, etc. Vitamin C plays an essential role in helping maintain and promote healthy collagen levels. It also helps wound healing, increases iron absorption and plays a role in how your immune system functions.

In terms of immunity, it helps promote the production of white blood cells, which can help fight off infections. As an antioxidant, Vitamin C also fights free radicals in the body which may promote healthy ageing and decrease your risk of other health conditions.

Does it really help with the common cold?

It’s a common misconception that Vitamin C is the gold equivalent of medicine for a cold, it can treat all sorts of symptoms and even prevent sickness. This claim has been around ever since a two-time Nobel Prize winner Linus Pauling claimed that taking large doses of Vitamin C could not only prevent the common cold, but also help stop more severe illnesses like cancer and heart disease. Since Pauling published his books in the 1970s, his bolder claims have not stood up to scientific scrutiny.

Even though Vitamin C may not keep you from catching a cold, some studies have shown that it may reduce its severity. According to a 2013 review , Vitamin C supplements taken during a cold can reduce the duration of the illness by 8% in adults and 14% in children. This means that taking Vitamin C supplements when you have a cold can shorten the duration of the cold by about one day. Participants in each study supplemented Vitamin C for varying periods, but generally, the daily dose was at least 200 milligrams.  The strongest effects occurred in people whose immune systems were weakened due to stress such as athletes or those consuming alcohol, smoking, living in a highly polluted area as Vitamin C also protects the body as an antioxidant.

Should we be supplementing?

Insufficient Vitamin C intake causes scurvy, which is characterized by fatigue (probably the result of impaired carnitine biosynthesis), malaise, inflammation of the gums, widespread connective tissue weakness, and capillary fragility. This was a massive problem in the 18th, 19th and 20th centuries, but with the increase in fortified cereals and breads as well as more widespread knowledge of the importance of Vitamin C, luckily this condition is rather rare nowadays.

In the US, the recommended amount of Vitamin C is 75 mg for women and 90 mg for men a day. With a varied diet rich in fruits and vegetables (at least 5 different portions of fruit/veg a day), we should all be able to achieve the daily recommended dose of Vitamin C at any time of the year.


Personally, I don’t believe Vitamin C is a must-have in your supplement cabinet, as most likely you’re getting enough of it through a healthy diet. Your multivitamins most likely also contain significant amounts of it. Although Vitamin C has an overall low toxicity risk in healthy individuals, consuming too much (>1000 mg) of it can cause some adverse gastrointestinal side effects including cramps, nausea, and diarrhea. A varied and balanced diet consisting of loads of fruit and veg is always the best foot forward. If you are worried about the amount you’re getting by possibly eating less varied foods or less fruits and veggies in general, then taking a supplement may be beneficial. However, make sure to consult your doctor before getting supplements to avoid overconsumption.

One Comment Add yours

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s