‘Tis the season…to catch a cold or the flu. The really excellent news is the NHS is predicting a "once-in-a-decade flu surge" this winter. Delightful.
Naturally, it's the perfect time to think about bolstering that immune system. Vitamin C is touted as one of the best immune-boosting supplements on the market, which explains why search around ‘vitamin C deficiency’ have spiked by 1,025% over the past month.
Vitamin C, also known as ascorbic acid, is an essential vitamin that our bodies need to function properly – from supporting our immune systems to keeping our skin, bones, blood vessels and cartilage healthy. "Every single cell and tissue within our body requires this nutrient for healthy function and repair,” says Shabir Daya, pharmacist and co-founder of Victoria Health.
The trouble is, vitamin C is water soluble, “so it's excreted out of the body within a very short space of time after ingesting it through food or by way of supplements,” Shabir notes. "Some vitamin C is retained within our organs and blood but, based on current research, we simply don't have sufficient vitamin C intake in the first instance, which exposes us to illness.”
Decreased levels of vitamins and minerals, “can affect various functions in the body, impacting our energy levels, mood and overall health,” adds Rhian Stephenson, nutritional therapist and founder of Artah.
That said, it's also important to manage expectations and not to see chugging a carton of orange juice or downing vitamin C supplements as a cure-all once you're laid up in bed with a runny nose and scratchy throat.
“Having a consistent and proactive approach is really the only way to help prevent the frequency and severity of illness," says Rhian. "So, it’s less about downing mega doses of vitamin C after we’ve fallen ill, and more about the consistent tools and habits we can implement to avoid getting ill in the first place.”
In this article:
→ What is vitamin C and what is it good for?
→ Can vitamin C cure a cold?
→ 7 Signs that you might want to up your vitamin C intake
→ Which foods are rich in vitamin C?
→ The best vitamin C supplements
→The biggest mistake people make when taking vitamin C supplements
→5 more ways to boost your immune system
What is vitamin C and what is it good for?
Vitamin C is a vitamin found in fruits (especially citrus) and vegetables. Your body doesn't produce vitamin C and it also can’t store it, which is why you need a vitamin C-rich diet to maintain healthy levels.
The benefits include:
- A boost in collagen production
A key role of vitamin C is to ramp up the body's efforts to produce collagen, a protein used to make cartilage, ligaments, skin and blood vessels. For this reason, vitamin C also helps with wound healing.
- Protection against oxidative stress and inflammation
Vitamin C is a potent antioxidant, which means it protects cells against free radicals — molecules produced when your body breaks down food or is exposed to UV rays and pollution. For this reason dermatologists swear by vitamin C serums applied underneath moisturiser and sunscreen. But taking vitamin C orally can also boost your defences. Free radicals are responsible for oxidative stress and inflammation, which have been linked to chronic illnesses, including heart disease.
- Vitamin C helps your body absorb and store iron
Blood loss from your period is one of the main causes of iron deficiency anaemia in women. Being able to absorb and store iron can avoid symptoms such as persistent fatigue, dry hair and shortness of breath.
- 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.
“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.
“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.
“Vitamin C is required for the manufacture of norepinephrine, a neurotransmitter that affects our mood and our ability to feel energised,” Shabir says.
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.
“Vitamin C improves its absorption,” she adds, which is why the Artah Essential Iron Complex includes both. It's also why the accepted advice is to knock back an iron supplement with orange juice.
Vitamin C deficiency can cause dry, brittle hair. “Vitamin C is good for your hair as it's vital for the absorption of iron,” says Anabel Kingsley, a consultant trichologist and brand president of Philip Kingsley clinics and hair care. While iron boosts circulation to the scalp and hair growth, being deficient in this mineral “can cause chronic hair loss and hair not growing past a certain length,” Anabel notes.
A lack of vitamin C slows down collagen production – and, in turn, wound healing. Vitamin C has anti-inflammatory properties; it can also nudge your skin to produce more proteins, including collagen, to repair damaged skin.
As Shabir explains, “Not only does vitamin C improve the structure of skin, it also improves its repair process.”
Bleeding gums are a sign of gingivitis – an early stage of periodontal disease, an infection that causes the gums to become inflamed. While there are many causes of gingivitis, including poor oral care, a recent study by the University of Washington involving 1,140 healthy subjects found that low vitamin C levels were associated with an increased risk of bleeding gums when gently prodded.
The researchers also concluded that increasing vitamin C intake may help to resolve the problem.
Noticing some weird changes to the hair on your arms and legs? Research has found that people with a vitamin C deficiency may have body hair that grows in a bent or corkscrew shape. The hair typically returns to normal within one month of adequate vitamin C consumption.
Which foods are rich in vitamin C?
Vitamin C is found in a wide variety of fruits and vegetables. As a water-soluble vitamin, just remember that vitamin C is easily lost through overcooking or boiling these foods, so consuming them raw is often better.
Try and include as many of these in your diet as possible:
- citrus fruits, such as oranges and grapefruits
- blackcurrants
- kiwis
- peppers
- strawberries
- blueberries
- broccoli
- brussels sprouts
- potatoes
- leafy greens, such as kale and spinach
“People who may be at a higher risk of developing vitamin C deficiency, such as those who are pregnant or breastfeeding, or have health conditions such as inflammatory bowel syndrome (IBS) and Type 1 diabetes, should ensure that their diets are rich in foods containing vitamin C," Dr Burke says. "If you need extra guidance, consult with your GP.”
The best vitamin C supplements
According to the NHS, adults aged 19 to 64 need 40mg of vitamin C a day (to put this into perspective, a large orange provides 50mg of vitamin C). The highest daily intake likely to pose no risks is 2,000mg per day.
While pills should never replace a vitamin C-rich diet, if you do choose to supplement, avoid unnecessary fillers (often listed as bulking agents) such as magnesium stearate and look for bioavailable formulas that the body can tolerate.
Also choose formulas designed to get the vitamin C into the bloodstream fast – without it being broken down in the stomach. “This is because vitamin C tablets, or any nutrient for that matter, have to pass through the harsh environment of the stomach, which deactivates large amounts of nutrients and medications,” Shabir says.
It's one reason why liposomal vitamin C is having a moment in the wellness spotlight. These are basically liquid supplements that encapsulate vitamin C within a lipid bubble (similar to the structure of the body's cells) to protect it against stomach acid and deliver it directly to cells.
The biggest mistake people make when taking vitamin C supplements
Another drawback to vitamin C being water-soluble is that it's easily lost through urine. Caffeine is a stimulant and has a diuretic effect, so your morning cup of coffee may mean your vitamin C doesn't absorb as well before being flushed out.
If you're a coffee lover, leave 30 minutes before or after caffeine to take your vitamin C supplement.
5 more ways to boost your immune system
- Cut down on sugar, alcohol and ultra processed foods
"These can suppress the immune system, so if you need some extra protection, it’s a good time to cut down," says Rhian. Studies have shown that meals high in sugar can reduce immunity for up to five hours, she adds.
2. Eat more plant-based foods
Given the link between gut health and immunity, she also recommends adding eight to 10 servings of vegetables and fruit each day. A simple way of loading up on beneficial foods is by adding immune-supporting herbs and spices such as ginger, turmeric, rosemary and garlic to your meals.
3. Get more sleep
Research has shown that both short- and long-term lack of sleep can result in immunodeficiency and higher levels of inflammation in the body. According to the Sleep Foundation one theory is that because your breathing and muscle activity slows down while you sleep, it frees up energy for the immune system to rev up and ‘remember’ how to recognise and react to dangerous antigens.
4. Try mindfulness of a relaxing yoga class - anything to help you relax
“Mental stress, anxiety and emotional upset can weaken immunity, and on the flip side, positive states like gratitude, joy and laughter have been shown to make our immune activity more efficient and robust,” says Rhian.
5. Take vitamin D3
Numerous studies have found vitamin D3 is crucial for a healthy immune system – research by Trinity College Dublin even found that vitamin D can help to prevent chest infections, particularly in adults with lower levels. A personal favourite of mine is Artah's Essential DE/K2 as it's a very bioavailable form of vitamin D3 (4000 IU), which it helpfully combines with vitamin K2 to ensure peak absorption.
Disclaimer: Vitamin supplements are not a replacement for a healthy balanced diet. Before supplementing, it's best to consult with your doctor and/or a registered dietitian.
For more from Fiona Embleton, GLAMOUR's Associate Beauty Director, follow her on @fiembleton.
