Showing posts with label research. Show all posts
Showing posts with label research. Show all posts

Thursday, September 29, 2011

The elusive vitamin D

I've been thinking a lot about vitamin D lately. A couple of people I know, whom I assume spend tons of time frolicking outdoors, were tested and found to be deficient. How could this be?, I wondered. I started reading a bit about it here and there, and found it to be a really confusing topic. There seem to be two conflicting viewpoints going around: a) that it is easy to get enough vitamin D from the casual sun exposure in all climes, or b) that most people are deficient in vitamin D, and universal supplementation is recommended. Surely, only one of these can be right! But how to tell which one? Or is there a magic solution somewhere in between the extremes?

The UK Departments of Health recommend that all pregnant and breastfeeding women and all children, ages 6 months to 5 years (unless drinking 500mL of fortified formula a day--regular milk isn't fortified in the UK), take a daily vitamin D supplement. While they say that regular sun exposure is adequate for most people, there have also been studies that found that more than half the adult population of the UK is vitamin D deficient, especially in the winter and spring. So not only is this confusing, you also have to keep in mind what the aim of recommendations like those from the DH are when trying to apply it to your own situation. Oh, public health, how I both love you and get annoyed by you at the same time! These recommendations are for populations. The DH knows that it is both safer and cheaper to recommend that everyone, or at least all people in "at risk" groups, take supplementation than that a small minority of those people end up with diseases like rickets and poor bone health. What the DH does not know is whether I, personally, or my family are actually deficient in vitamin D and could benefit from supplementation. So while it is useful to consider the official advice, it doesn't tell me the whole story.

Gus soaking up some rays in the back garden
Today I read this post over on Best for Babes (and this follow-up on the author's own blog) and found it really useful. It is still obviously talking about populations, but at least it is providing me with context, not just a one-size-fits-all approach. There's a bit of a philosophical debate within breastfeeding circles regarding vitamin D. If breastmilk is complete nutrition for your baby, providing everything baby needs for at least the first 6 months of life (which I believe it is!), then why should we need to give vitamin D supplements? Is it somehow betraying breastfeeding to suggest that vitamin D supplementation can be useful, or even necessary? The author, Diana Cassar-Uhl, looks extensively at the research surrounding vitamin D deficiency, sufficiency, and supplementation. All extremely useful; just what I was looking for. In particular, she reports that studies show that it is very hard for our bodies to make enough vitamin D from the sun at higher latitudes (i.e. where the UK is), especially in the winter months. But the thing that really helped me wrap my head around the issue of giving vitamin supplements to babies was this: if older children and adults only get 10% of the necessary vitamin D from our diet, why should we expect infants to have 100% of the need met through diet alone (breastmilk)? It is probably possible for a baby to get it all through breastmilk, if the mother's stores are high enough, but is it necessary? I don't know the "right" answer to that question, but, to me and for my family, I would say it is not. There are other sources, i.e. sun exposure and vitamin supplementation, that can play their part.

Way back in the day, people would have gotten enough vitamin D through sun exposure, as they would spend hours outside everyday working in the fields, washing laundry at the creek, etc, etc. But for me, that is simply not possible. So I am going to try to get it in whatever way I can. I try to take Gus outside for an hour every day when the weather is nice. (Of course, this opens up the whole question of what is the optimal amount of time to go without sunscreen or other protection from the sun--most sources seem to say between 15 and 30 minutes. Especially since Gus is so fair compared to my own complexion! I have never had to worry about sunburn for myself, but I don't want risk him burning.) To make up the difference between what we can synthesize from the sun and what we need, especially in the winter--and, often, rainy summer!--months, I am going to give Gus vitamin D drops. (There is already vitamin D in the daily multivitamin I [try to] take since I am breastfeeding.) I don't have any problem giving these to Gus, since he is already eating solid foods--especially if I can get the kind with no sugars, flavourings, colors, etc, which don't appear to be available in the UK. But, no worries, I've got connections ;)  When we have another baby in the future (God willing!), I think I will try to get my own levels tested and then take enough supplements myself to provide a sufficient amount to the baby, so I wouldn't have to give drops before 6 months, if possible. Jon takes a multivitamin, but it doesn't seem to have vitamin D in it, so I should probably look into a separate supplement for him as well, especially since he sees the least amount of sun out of all of us!

I am really glad I have come to a conclusion regarding this issue. I was pretty sure I was going to give Gus the drops anyway, but now I feel I really understand why it is a good idea for us. What about you--do you supplement? Why or why not?