MS Patient, Ph.D.: MS and Vitamin D: What’s a Patient to Do?

The answer is easy for me: When I first started having symptoms, no one tested my vitamin D values. A few years later, a listening neurologist dispatched me for testing, although I told him about my habits involving sun and dairy and fatty fish, positive that my vitamin D was fine. He was right; I was wrong. My values were at the border of osteomalacia threat level 5 (i.e., <30 ng/mL), and my neurologist put me on vitamin D supplements—5,000 IU a day.

That might seem like a huge amount relative to the recommended daily dose of 600 IU. It seems not as huge if you consider that just 20 minutes without sunblock at the beach could net me 10,000 IU. But after a year of that supplementation, a follow-up blood test showed my levels had reached just within the normal range. So, I’ve stuck with the 5000-IU daily replacement.

My levels struggle this way even though my mother, who has some crunchy tendencies, poured cod liver oil down our throats and had us swallowing vitamin D supplements every day of our childhoods. In fact, she still offers me cod liver oil whenever I visit. Add to this that I wear sunscreen only on my face, a habit I developed just recently. I get substantial sun on all my other body parts. I drink milk and eat cheese and yogurt and sour cream. My greatest aquatic protein weakness is fatty fish, and I eat eggs at least on the weekends. Sure, my cholesterol might suffer (actually, it’s fine), but vitamin D-wise, my lifestyle should have left me well stocked without the need for supplements.

So what’s my problem? How in the name of Apollo can I do all of these vitamin D-boosting things and still not have enough vitamin D? How can I take in almost 10 times the recommended amount and have levels that just barely fall within normal range?

As a scientist, I find the likeliest answer must be that I’m just not processing what I get very efficiently into usable form. Studies have suggested that low vitamin D levels and MS are involved in a complex dance, but what has remained unclear is whether MS influences the body’s processing of vitamin D or if vitamin D influences the development and progress of MS.

Of course, the mechanistic data that are available arise from studies with mostly RRMS populations. Some work suggests that the promoter of an MS-specific haplotype contains a vitamin D response element. A study with a mouse model of a demyelinating disease suggests an interaction of vitamin D and cytokine signaling. Larger clinical trials to evaluate if vitamin D supplementation at higher doses—e.g., 4000 IU, the ceiling that an Institute of Medicine panel recommended—are in process or just completed.

One study just published in JAMA Neurology indicates that starting out with low levels of vitamin D can be predictive of a more rapidly worsening evolution of MS. It’s yet another correlational study, but it adds another span to the bridge linking MS and vitamin D. Of course, by virtue of sheer mathematics, the representation of people with progressive MS in these trials will necessarily be small. Will those with progressive disease experience different outcomes? We don’t know, but we need vitamin D for all kinds of physiological processes, MS or not, so I’ll continue my supplementation.

I didn’t start taking vitamin D supplements until 6 years after my symptoms began. According to this most recent study and at least one MS specialist, Gavin Giovannoni, M.D. (a member of MSDF’s Scientific Advisory Board), I should have been doing that all along. Indeed, as Giovannoni writes at his blog, not only does he tell his patients to take 5000 IU/day, but he also urges his family to do so and does so himself. The problem, he says, is getting his family “to adhere to the supplements.” My mother could probably relate, and it will likely make her feel a lot better on my next visit when she offers me cod liver oil, again, and this time, I say yes. Like I said, at this point, it’s an easy answer.

Read other MS Patient, Ph.D. blog posts.