• Vitamin C is essential for eight major enzyme systems in our bodies

“Enzymes are protein molecules that are required for the body to function correctly. Without enzymes, we would not be able to breathe, drink, digest and even excrete,” Shabir notes.

Can vitamin C cure a cold?

Ah, the million dollar question – and the subject of many studies. The bottom line seems to be that vitamin C isn’t a natural cold remedy and it’s unlikely to magically stop you catching a cold from the sick person sitting next to you.

According to an article published by Harvard Health, the bulk of evidence shows that high-dose vitamin C will, at most, shorten a cold by one day.

But there does seem to be a consensus among our experts that vitamin C can support the immune system. Shabir notes that while it’s not entirely known how vitamin C does this, “studies do indicate that supplementing vitamin C can reduce the incidences of colds.”

On the flip side, lower levels of vitamin C “can compromise the immune system, putting you at greater risk of sickness, infections and viruses over winter,” adds Dr John Burke, a GP with over 25 years experience and AXA Health‘s chief medical officer.

8 signs that you might want to up your vitamin C intake

To avoid scare-mongering, it’s highly unlikely that you’re actually deficient in vitamin C as we have access to plenty of fresh fruit and vegetables (smokers beware, though, as puffing on cigarettes reduces the absorption of vitamin C).

There are, however, telltale signs that your reserves may be running low and that you may not be taking your vitamin C supplement correctly.

1.You’re suddenly catching every cold doing the rounds

“Each stage of our immune response relies on the presence of different micronutrients, which are critical to its function, like vitamin C, vitamin D, zinc, selenium, vitamin A, iron and different amino acids,” says Rhian.

Studies show that vitamin C, in particular, is found at high levels inside many immune cells to help your body combat infection.

2. Your skin is dry and rough

“Skin is your largest organ and it can say a lot about your health,” notes Shabir. “A lot of nutrients that are famously found in skincare, including vitamin C, have to be provided from within the body to make a real difference to the skin.

“Increasing your dietary intake of vitamin C has been correlated with a decreased risk of dry skin,” he continues. “Studies indicate that vitamin C enhances the production of barrier lipids, called ceramides, which protect skin against water loss.”

Given vitamin C also plays a role in collagen production – a protein responsible for strengthening the skin’s structure and keeping it looking plump – it follows that when vitamin C levels are low, skin can become dry, wrinkled and rough to the touch.

3. You’re often tired and grumpy

“Vitamin C is required for the manufacture of norepinephrine, a neurotransmitter that affects our mood and our ability to feel energised,” Shabir says.

4. You’re low in iron

Iron deficiency anaemia and vitamin C often go hand in hand. “Iron is involved in red blood cell formation and is required to transport oxygen throughout our entire body, making it an essential mineral for energy, immunity, cognitive function, and pregnancy,” says Rhian.