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Monday, May 16, 2011

The Snake Oil Salesman’s Guide to Vitamin A

by Mark Dunning

You should take vitamin A. You should give it to your children. You should take it, of course, in a dose that is safe and prescribed by a physician, but you should take it. My daughter takes vitamin A and her vision has not changed perceptibly in the last four years. I have a friend who has two daughters that take vitamin A. Their vision has not changed in nearly a decade. You should take vitamin A.


Don’t act on that!

The above is true about my daughter and my friend’s children. They all take vitamin A and their vision has not changed for a number of years. That does not mean, however, that vitamin A is the reason. It might be, it might not be. We don’t know.

In spite of that first paragraph, I’m really not going to get in to the problems with the vitamin A study or argue that it should be prescribed to everyone with Usher. No, today I’m going to vent my frustration at the scientific community. Sorry, but you guys have dropped the ball.

There is little more controversial in the Usher community than vitamin A and I have to say it drives me bananas (which are not high in vitamin A, by the way). I am not a scientist or a physician. I read all I can on Usher syndrome and have learned a lot. I regularly blog about Usher syndrome, but the truth is I’m still just a dad trying to do the right thing for his child. But I don’t know what the right thing is when it comes to vitamin A.

Many doctors and researchers I trust offer a tepid endorsement of vitamin A. Many others, including a certain person that shares this space, don’t believe the current research justifies vitamin A as a treatment for Usher syndrome. And there are a couple of doctors on both sides who are fervent in either their support or their opposition to vitamin A. In the middle are families, like mine, left to make a decision with a paucity of information and, quite frankly, a ton of conjecture.

Let me take a moment to praise my friend Jennifer. Her posting on vitamin A does a good job of reviewing the studies done to date and laying out the facts. I’m paraphrasing here, but in her opinion, based on the currently available studies, she would not give her child vitamin A as a treatment for RP. I have read the same studies and have a different opinion. Hence, my daughter does take vitamin A.

But here’s where I agree with Jennifer. We need more studies on vitamin A! The study done by Dr. Berson and his colleagues is an excellent study that has followed hundreds of families for decades. The study suggests that vitamin A has the potential to be a successful treatment for retinitis pigmentosa. But it leaves more questions unanswered than it answers.

So why have there been no other studies on vitamin A? Why haven’t other scientists and researchers and physicians sought to answer the questions that have arisen from the original study? Would a potential treatment for cancer sit unconfirmed for this long? For as good as it is, there are problems with the original study. Dr. Berson and his colleagues would be the first to admit it. Heck, they spend a lot of time trying to answer the questions that remain open. But that’s part of the problem. Dr. Berson and his colleagues should not be the only ones answering the questions.

The best science is that which is proven over and over again by different studies performed by different researchers. Imagine if we had three different studies that drew the same conclusions as Dr. Berson’s original study. What would be the advice given to families then? Or imagine the flip side, where three other independent studies found that vitamin A has no effect, or worse, an adverse effect on RP. What would we do then?

Instead families are left to guess and to draw conclusions from an impossibly small sample size. We have essentially one study and the word of mouth of other families, both pro and con. Families should not be listening to me on this subject! (Seriously) Jennifer has written about sham science and I am the embodiment of that. Bella is one kid out of thousands with Usher. Maybe her experience is just the normal progression of the disease. Maybe (and I pray this isn’t true) her vision would be better if she didn’t take vitamin A.

The point is we don’t know. If I were truly a Snake oil salesman, I would present the experience of my family and of my friend’s family as proof positive that Vitamin A is THE CURE for Retinitis Pigmentosa. But I can’t sell that in good faith. Just because I write a blog on Usher and sound like I know what I’m talking about doesn’t mean my opinion on Vitamin A should matter.

The good news is that there is a way through this uncertainty. It’s called science! Do more studies on vitamin A. Answer all the questions. Take the guess work out of it and find the truth. I’ll even help write the grant proposals (writing is about all I’m qualified to contribute). Families will do the right thing once the proof is there. We just need to know what it is.

We need a consensus on vitamin A. My daughter’s vision, and my sanity, depend on it.


MKChaikof said...

Thank you for writing this. It sums up my feelings of frustration completely.

JillyBean said...

I was wondering where you find your information? and would you be willing to share? I have usher type 2 and I'm trying to find out anything I can, but I feel like I keep hitting a wall. I'm not too sure where to look. So any help you could offer would be so wonderful.
I also write a blog on my experiences too and if you want you can check it out.

Thanks again.

Mark Dunning said...

Hi Jill,

The best source for Usher syndrome information on the internet is probably the Coalition for Usher Syndrome Research web site, In particular, if you join the family network on the site, you will be added to their mailing list and get all the latest news on Usher research.

From that site you can also find links to other sites such as the Foundation Fighting Blindness that also have good information on Usher syndrome.

I would also recommend attending one of the Coalition's family conferences such as the one being held July 8th in Sturbridge, MA.

Brad said...

Hi Mark - your thoughts here are one of the many resons why I don't and won't be taking Vit A, at present. Cheers, Brad