Vitamin D may play a crucial role in immune functioning. A study of nearly 1000 senior citizens in Northern Ireland measured inflammatory markers such as C-reactive protein, Interleukins 6 and 10 and TNF-alpha. Those with 25-hydroxyvitamin D levels below 10 nanograms per ml were significantly more likely to have unfavorable results compared to those with levels greater than 30. The researchers conclude, “These findings suggest that an adequate vitamin D status may be required for optimal immune function, particularly within the older adult population.”
[Journal of Clinical Endocrinology and Metabolism, online Feb 25, 2014]
Some of our readers have reached this conclusion on their own. LJ remarked:
“I have been taking a vitamin D supplement for the past 20 years and feel confident that it contributes to my well being at the age of 82, agile, active and pain free.”
FBL had a different experience:
“My D level has always been low when tested. My Dr. first had me do sun baths and they made NO difference; then he had me taking vitamin D, and increasing, and increasing. My level finally got up to 40 when I was diagnosed with cervical cancer three years ago.
“I had not had a cold or flu since ’85 even with low D. After my cancer diagnoses my Dr. wanted my level up to 100. No, I’m not there yet but getting close. I’m up to six 5,000 iu caplets a day now. I’ll get tested again in a few months.
“The message here is one MUST get tested. Every body is different. My son got tested too and his was low as well, even with running out in the sun every day.”
You will find more information about vitamin D, home testing of blood levels and supplementation in our Guide to Vitamin D Deficiency.