Linus Pauling made a Typo: It was D, NOT C for Colds
Competency # 17 Vitamin D
Reference: Ginde et al, Arch Intern Med. 2009;169(4):384-390
We’ve spent 40 years trying to find out the proof that Vitamin C helps prevent colds. If there is any proof, it’s thin. Despite all the ads on TV about orange juice and Vitamin C and colds, Vitamin C just doesn’t deliver like we hoped it would. Could Linus have been a lousy typist and just had a typo? I believe he really meant to hit the D key, and missed! It wasn’t C. It was D.
Now, our most reliable database on health and nutrition, the third National Health and Nutrition Examination Survey data has been plumbed to find the truth. A national survey of colds and vitamin D levels (1988-1994) with over 19,000 randomized US citizens was conducted. Extensive questionnaires about recent health and then physical exams and blood work with a mobile lab were done. Vitamin D levels were collected as part of a broad series of tests.
This is the first huge population survey to look at D and colds. What they found is very powerful. If your D level drops below 10 ngs, you have a 567% increased risk of a cold if you have asthma compared to normal folks with a level of 30 ngs. If you had COPD, your risks were 226% higher for a cold. If you didn’t have asthma or COPD, your risk only rises by 25%. That still is huge. Your risk of getting a cold drops 25% for everyone if you have enough D.
The mechanism for how D works is pretty well worked out. D stimulates the production of a protein called cathelicidin (hCAP-18) . Cathelicidin is your natural antibiotic. It helps you kill germs by encouraging white cells to get to the site of infection and gobble up germs. hCAP-18 is directly produced when you have adequate D and it’s hCAP-18 that turns on your white cells. And it all depends on D level. Below 10 ngs and you are in trouble. From 10-30, they see intermediate risk of colds. Above 30 ng and it appeared that the effect plateaus off, though the researchers admit the study was too small to be able to see if there was an optimal level above 30 ngs.
During the summer, many Caucasians in Wisconsin will get to 40-50 ng with sensible sun exposure. By October, that level is falling and as a population we hit 30 somewhere around November 1. And we start getting colds when? (Hint: Nov 2). Measurements of our African American community in Milwaukee show an average D level of 15 in late summer and winter. Hence, the more skin pigment you have, the more risk you have for colds for a longer period of time during the winter.
WWW: What will work for me? Well, we know you can raise your D level by 15 ng in two days with a single 100,000 IU dose of D. I am not telling my patients with colds and with asthma or COPD to take 10,000 IU a day for a month, but I might start talking about 100,000 all at once as soon as they get a cold if they have never taken D before. I’ve had more than one person say they got better in just a day or two from the “same cold that everyone else was out for a week with” when they took 50,000 IU all at once. Pauling was right. We need a supplement when we get a cold. He was just a lousy typist and couldn’t spell. I can relate to that.