Introduction:

A Closer Look at Neutrophils 

In the intricate dance of our immune system, one group of foot soldiers stands out: neutrophils. These tiny yet mighty cells patrol our bloodstream, ready to defend against any foreign invaders that dare to threaten our well-being. Neutrophils are an essential part of the innate immune system, an evolutionary masterpiece that requires no prior training to combat threats effectively.

Neutrophils’ Swift Response

Neutrophils are the rapid responders of our immune system. As soon as they sense a threat – be it a virus or bacteria – these vigilant cells spring into action. They don’t hesitate; they engulf and destroy the invaders on sight, including the notorious coronaviruses.

Neutrophils’ Secret Weapon – Vitamin C

Here’s the captivating twist in this story: neutrophils rely heavily on vitamin C to carry out their mission. This vital nutrient is their secret weapon. Neutrophils use vitamin C to migrate to the sites in our bodies where viruses or bacteria have taken refuge, primarily our lungs, ground zero for respiratory infections.

Not only do they need vitamin C for mobilization, but they also use it to engulf viruses and bacteria, turning them into harmless prey. Moreover, vitamin C equips neutrophils with the power to generate free radicals, which are potent virus and bacteria killers.

The Vitamin C Delivery System

Picture this: specialized pumps in the outer layer of neutrophils’ skin function as gatekeepers, ushering vitamin C from our bloodstream into the core of these infection-fighting cells. This intricate mechanism ensures that neutrophils have ample vitamin C to fulfil their crucial roles.

The Role of Vitamin C Intake

Optimizing vitamin C intake is essential for maintaining robust neutrophil function and overall immune health. Studies have shown that a daily intake of 200 mg of vitamin C is sufficient for young, healthy individuals to maintain a minimum blood vitamin C level of 50 umol/L – a level associated with optimal immune function.

However, as we age, our vitamin C requirements evolve. For those over 60, researchers recommend 1000 mg of vitamin C per day, ideally split into two doses. These adjustments account for the natural decline in vitamin C absorption and utilization that accompanies aging.

Vitamin C in the Face of Infection

When confronted with a respiratory tract infection, be it the common cold, flu, or something more sinister like COVID-19, neutrophils undergo a dramatic change. They deplete their vitamin C reserves at an astonishing rate. To keep their infection-fighting capabilities at their peak, they require a substantial influx of vitamin C.

Studies underscore the significance of this need. Gram doses of vitamin C become necessary once an infection takes hold, leading to peak plasma ascorbate concentrations of greater than 150 µmol/L – a desirable level during an infection.

The Consequences of Vitamin C Deficiency

When neutrophils are deprived of sufficient vitamin C, they resort to an alternative defence mechanism: the release of fibrous strands known as NETs (Neutrophil Extracellular Traps). While NETs can capture and neutralize viruses, they come at a steep cost. They trigger an immune cascade, resulting in a cytokine storm – a vicious cycle of inflammation that can lead to organ failure and abnormal blood clotting.

Recent studies offer a glimmer of hope. Providing sepsis patients with high-dose vitamin C supplementation has shown promising results in preventing deaths. However, waiting until infection reaches this advanced stage may not be the wisest approach.

The Proactive Approach to Immune Health

Rather than leaving our immune system vulnerable, it’s wiser to take a proactive stance. Supporting neutrophil function by maintaining adequate vitamin C levels is a simple yet effective strategy. For those in good health, a daily intake of 200-1000 mg of vitamin C can bolster immune readiness.

Vigilance in Times of Infection

In the face of an impending respiratory tract infection, vigilance is key. At the first sign of trouble, be it a scratchy throat or sniffles, consider a minimum daily dosage of 500 mg of vitamin C, split into four doses. This regimen has demonstrated its ability to support neutrophil function, deter the release of NETs, and prevent a dangerous cytokine storm.

In conclusion, the bond between vitamin C and neutrophils in safeguarding our immune health is undeniable. With the wisdom of optimal vitamin C intake, we empower our immune system’s rapid responders to act decisively and protect us from the perils of infection.

References:

1. Bozonet SM and Carr AC. The role of physiological vitamin C concentrations on key functions of neutrophils isolated from healthy individuals. Nutrients June 2019. 11,1363.
2. [Link to Book Excerpt](https://books.google.ca/books?id=vc3LDwAAQBAJ&pg=PT149&lpg=PT149&dq=NETs+vitamin+C+and+neutrophils&source=bl&ots=HLGF1c86g_&sig=ACfU3U3eSCG30ickkzlMeGmd87bIfECJ6g&hl=en&sa=X&ved=2ahUKEwjJgqPZ0c_pAhVVZ80KHUhzBDgQ6AEwD3oECAkQAQ#v=onepage&q=NETs%20vitamin%20C%20and%20neutrophils&f=false)
3. [Link to Research Article](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4743982/)
4. [Link to Research Article](https://ashpublications.org/blood/article/129/10/1357/36005/Platelets-and-neutrophil-extracellular-traps)
5. [Link to Research Article](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6950903/)
6. [Link to Research Article](https://jamanetwork.com/journals/jama/fullarticle/2752063)
7. [Link to Research Article](https://www.researchgate.net/publication/336201419_Effect_of_Vitamin_C_Infusion_on_Organ_Failure_and_Biomarkers_of_Inflammation_and_Vascular_Injury_in_Patients_With_Sepsis_and_Severe_Acute_Respiratory_Failure_The_CITRIS-ALI_Randomized_Clinical_Trial)
8. [Link to Research Article](https://annalsofintensivecare.springeropen.com/articles/10.1186/s13613-020-0640-6)
9.  [Link to News Article](https://www.news-medical.net/news/20191001/Vitamin-C-improves-survival-rate-in-sepsis-and-acute-respiratory-distress-syndrome-(ARDS).aspx)

Dr. Meschino