Is Vitamin C Useful For Preventing Or Treating Cold And Flu?

The Vital Vitamin C

The Caustic Cold and Flu!
One can perhaps never have everything to prevent or fight cold and flu! Stuffy nose, chills, fever, weakness, body ache: symptoms of one of the most common and exasperating illnesses that remains undeterred and precisely irremediable despite extensive ongoing worldwide research. Though the volatile viruses give very little scope to combat them, symptomatic allopathy, home remedies, alternative medicines and naturopathy have been partially fruitful in tackling their manifestation by boosting immunity, of which the most prevailing practice is stepping up vitamin consumption.

Apart from contributing to growth and development of an organism, vitamins play an exceptional role in prevention and treatment of a myriad of diseases and their deficiencies can lead to debilitating disorders. The treatment regimen mostly consists of vitamin supplementation and additional therapeutic interventions (invasive or non-invasive). One such popular belief speaks about the benefit of vitamin C in preventing and treating cold and flu. Vitamin C or ascorbic acid is a water-soluble vitamin and one of the strongest antioxidants known, which cannot be manufactured in the body and hence is required through dietary intake.

How does Vitamin C affect our immune system?
We have a strong immune defense to resist and encounter infections or toxins. But before any infection swarms the system it has to get across body’s first line of defense, the skin and mucous membrane. Vitamin C is the key nutrient for synthesis of collagen that reinforces the skin’s tensile strength bolstering it up for pathogenic invasion and accelerates wound healing. Also, it promotes free radical-scavenging activity of the skin, thereby potentially protecting it against environmental oxidative stress. Systemically, vitamin C supports and empowers the innate as well as adaptive immune system. During an infection or inflammation, there is a higher requirement of vitamin C to enhance antibody production by B cells, microbial killing by phagocytes (cells that engulf and kill pathogens) and the white blood cells by promoting cell proliferation and metabolic reinforcement to expedite the battle!

The white blood cells are responsible for fighting, protecting against and eliminating infectious pathogens or foreign particles. They have membrane bound-vitamin C transporter molecules that can localize vitamin C into the cells during periods of high metabolic demand. That explains why there is a drastic drop in vitamin C levels and consequentially increased requirement of it during an infection or an inflammatory condition!

How much, how often, the Ifs and the Buts!
The recommended permissible dose of vitamin C is around 90 mg per day though one may needs to up this daily dose to about 1000-2000mg alongside a vitamin-rich diet, to exhibit noticeable boost in immunity and subsequent therapeutic advantage. A few small trials showed that a 1000 mg/day dose of vitamin C supplementation shortened the duration and mitigated severity and symptoms of cold by 5-20% if consumed religiously for a prolonged period.  At the same time, such high doses of vitamin C taken regularly increase the risk of gastric disturbances, diarrhea, nausea, headache and insomnia in an otherwise healthy individual. And this vicious cycle has been placing vitamin C in the confession box time and again.

The viral defense outsmarts our immune defense through genetic modulations

The Ingineous Genetic Power of the Pathogens
A crucial aspect that beats the vitamin C conflict black and blue is the nature of causative pathogens of Cold and Flu; viruses like rhinovirus, influenza viruses are some of nature’s most enigmatic pathogens. On their first encounter with our immune system, they triggers the production of antibodies that recognize them and build up a memory squad against the viruses. But these viruses have an innate ability to go through subtle changes in their genes (mutations) during replication, over varied time duration, that end up creating newer strains of the same parent virus. This is called ‘antigenic drift or antigenic shift’. The antibodies subsequently do not recognize these variant forms on their next encounter and are unable to restrain the infectious cycle. To exemplify, a rhinovirus can mutate upto 800 different antigenic forms during a single cycle of infection. That is why it is practically impossible to create a vaccine against common cold and it remains the most frequently encountered infection during a human’s lifespan!
This brings us to a critical inference. That, whether or not you are well equipped with sufficient vitamin C ammunition, these viruses always have a heavier counter-cannon to weigh you down: the battery of explosive antigenic drifts!

The 'cold' war!

To sum up, although these facts do establish a critical role of vitamin C as an immune-enhancer and in maintaining the epithelial barrier function, few physiological bottlenecks like dosage, adverse events and genetics have left researchers tight spotted in giving thorough affirmation to prophylactic or therapeutic benefits of vitamin C.  Nevertheless, they do advocate that incorporating a vitamin C rich diet comprising of broccoli, tomatoes, spinach and citrus fruits to name a few, or supplements can alleviate the severity of symptoms of common cold and flu and venture a tiny punch, if not a knock-out to these voracious viruses!

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