Vitamin C holds a prominent place in health discussions, often associated with its ability to fend off colds, enhance immunity, and combat severe illnesses.
However, while it is vital for bodily functions, the advantages of Vitamin C are sometimes misinterpreted or exaggerated. Before investing in supplements, here’s what you need to know.
What is vitamin C and why does my body need it?
Vitamin C, or ascorbic acid, is crucial for various bodily functions.
It acts as a potent antioxidant, safeguarding cells from damage. It also bolsters the immune system, aids iron absorption, and plays a role in wound repair.
Moreover, Vitamin C is essential for collagen production, which is vital for holding tissues together and is a key component of gums and skin.
A significant lack of Vitamin C can result in scurvy, a condition where collagen production is insufficient, leading to weakened tissue. This can cause gums to lose teeth and blood vessels to deteriorate, resulting in internal bleeding.
Humans cannot produce Vitamin C naturally, thus it must be acquired through the diet. Most Vitamin C intake comes from vegetables (about 40%), fruits (19%), and vegetable or fruit juices (29%).
The Vitamin C in supplements is chemically identical to that in food, and the body cannot distinguish between the two.
However, supplements lack the fibre, flavonoids, other vitamins, minerals, and phytochemicals found in food that may work synergistically with Vitamin C.
These compounds assist in absorption, offer additional antioxidants, and contribute to health benefits that Vitamin C alone cannot provide.
Historically, sailors with restricted diets often suffered from scurvy. But with a balanced diet, Vitamin C supplements are unnecessary.
What does vitamin C treat and not treat?
Common cold
Vitamin C is commonly believed to enhance the immune system and is thought to prevent and treat colds and flu.
However, a thorough review of evidence indicates that regular consumption of 200 mg or more does not lower the incidence of colds.
While regular supplementation can decrease the duration, and doses over 1,000 mg may lessen the severity of symptoms, taking Vitamin C at the onset of a cold does not affect the duration or severity.
Some studies suggest a marginal benefit from daily supplementation before illness, but overall, routine use is not deemed beneficial.
Heart disease and stroke
Research indicates that Vitamin C supplementation does not alter the risk of cardiovascular diseases such as heart attack, stroke, or angina.
One study suggests that doses over 200 mg might slightly lower blood pressure, but these changes are minimal and not as significant as those achieved through conventional medicine or regular exercise.
Cancer
Consistent findings from multiple studies reveal that Vitamin C supplements do not prevent cancer, including gastrointestinal, lung, breast, prostate, and colorectal cancers.
Is it possible to take too much vitamin C?
The Recommended Daily Intake (RDI) for adults is 45 mg per day, easily obtained from a small glass of orange juice.
The tolerable upper intake level is 2,000 mg daily for adults.
Since Vitamin C is water-soluble and excreted in urine, the body cannot store it, and excessive intake offers no added advantage, potentially leading to health issues.
High doses (over 2,000 mg daily) may lead to side effects like diarrhoea, nausea, and abdominal cramps. It can also cause kidney stones in men, but not women.
For those with chronic kidney disease, Vitamin C can be particularly troublesome as it is expelled by the kidneys, and malfunctioning kidneys can lead to an accumulation, causing kidney stones.
Related: A Common Vitamin Could Help Protect Your Lungs From Air Pollution
Should you take a vitamin C supplement?
Most individuals do not need Vitamin C tablets, as a balanced diet provides sufficient amounts, with sources like citrus fruits, berries, tomatoes, capsicum, broccoli, and kale.
Current evidence does not support the claim that Vitamin C supplements prevent colds, heart disease, or cancer, and the potential risks may outweigh the benefits.
Nial Wheate, Professor, School of Natural Sciences, Macquarie University; Ian Jamie, Senior Lecturer, School of Natural Sciences, Macquarie University, and Wai-Jo Jocelin Chan, Pharmacist and Lecturer, UNSW Sydney; University of Sydney
This article is republished from The Conversation under a Creative Commons license. Read the original article.
