I think the main reason most people are not resistant to infection is generally low vitamin D status.
This paper will help you understand how vitamin D in skin responds to infection.
The vitamin D pathway: a new target for control of the skin’s immune response?
But of course for the immune system to kick into action with sufficient power and with the ability to control it's pro and anti inflammatory roles you need a reserve of D3 in your body available for use as required. This is why we need a 25(OH)D level around 60ng/ml or certainly above 50ng/ml. It's only between 40~50ng/ml we see the stored reserve of D3 in muscle and fat cells increasing.
Circulating Vitamin D3 and 25-hydroxyvitamin D in Humans
By chance this is in todays updates.
Vitamin D Status Relative to Diet, Lifestyle, Injury and Illness in College Athletes.
Quote:
Using 40 ng/mL as the cutoff for optimal status, 75.6 %, 15.2% and 36.0% of athletes had optimal status in the fall, winter and spring, respectively. 25(OH)D concentrations were significantly (P <0.05) correlated with multivitamin intake in the winter (r=0.39) and tanning bed use in the spring (r=0.48), however, status was otherwise not related to intake, lifestyle factors or body composition. 25(OH)D concentrations in the spring (r=-0.40; P=0.048) was correlated with frequency of illness. CONCLUSION:: Our results suggest that collegiate athletes can maintain sufficient status during the fall and spring but would benefit from supplementation during the winter to prevent seasonal decreases in 25(OH)D concentrations. Results further suggest that insufficient vitamin D status may increase risk for frequent illness. Future research is needed to identify whether vitamin D status influences injury risk during athletic training/competition.
|
The average USA adult only ever at best (end of summer 30ng/ml has about half that amount but mostly we run about 15~25ng/ml .
If you drove your car with tyres inflated at 25%~ 50% the manufacturer's original specifications you'd have more accidents and incidents. Only morons drive with under inflated tyres, yet very few people bother to check and correct 25(OH)D status.[/quote]
Vitamin D Induces Innate Antibacterial Responses
40ng/ml isn't a sensible option for optimal status as at that level there are NO STORED RESERVES OF VITAMIN D3.
It's a bit like trying to go to war without any reserves of ammunition to sustain any offensive action. If every time you were attacked you had to wait while you made some new ammunition before you could respond the enemy would always have the advantage.
Why is it sensible to only have sufficient vitamin D3 available to just cover your daily needs?
Surely health professionals should be promoting 25(OH)D levels associated with least chronic illness not trying to make people ever more dependent on medical drug interventions?