Several years back, there was quite a stir when a study suggested that Vitamin A, in smokers, was a bad thing. There was a small, but significant increase in lung cancer, in smokers who took vitamin A and in those with asbestos exposure. Since that time, those studies (there were actually 2 of them, dating about 12 and 9 years ago respectively) were questioned and the findings flawed, but that was back page news and not front page news. To this day, these ancient studies are still cited on the internet, when the agenda of the writer calls for it. This type of “journalism” is nothing new.**
A well known alternative health guru released an article, while back citing a study that suggested Vitamin A might increase colon cancer by interfering with Vitamin D absorption. I read the study and it had nothing to do with Vitamin A causing colon cancer and that was not even the point of the study. Still, by virtue of position of this individual, the audience they command, for better or worse, took up the cross. I have read Dr Michael Holick’s extensive tome on Vitamin D and there is not one word about Vitamin A interfering with Vitamin D, or causing colon cancer, either.
There has been some controversy about Vitamin A and gastric cancer, especially in the Japanese population. While the debate will likely continue, the most recent published articles suggest that Vitamin A may indeed prevent it!
Most recently, the Vital Study showed a probable decrease in Melanoma, in people taking huge doses of Vitamin A (retinol). Specifically, up to 40% reduction of this deadly cancer, a cancer which is on the rise because of sun exposure.
Lots of people forget the association of Vitamin A deficiency with many diseases. In a nutshell, Vitamin A has an essential role in energy metabolism and regulation. This includes fat burning, by the way- something to note if you are struggling with your weight. Now, it would be rare for a Western person to have a full blown Vitamin A deficiency. But Vitamin science is, just now, beginning to understand relative deficiencies, especially those associated with aging. Vitamin A’s essential role in energy metabolism should be considered, when we look at the aging of our cellular powerhouses, the mitochondria.
Finally, Vitamin A is an absolute must for a healthy immune system, healthy skin and of course healthy eyes and immune responses.
So what can we make of all this? Well, I hope you are not too disappointed, but I can conclude only 4 things for sure, from my review of dozens of studies over the past decade.
1) Don’t smoke and if you do quit now!
2) If you are at high risk for melanoma, (see Melanoma Risk Factors) you might want to consider adding Vitamin A to your routine, or at least taking a multi with 5000IU or more.
3) Conspiracy sells, far more than fact.
4) Science does not help with #3 as much as we’d like, since answering questions, once and for all, puts an end to grant money!
Please, do not be afraid of Vitamin A!
**The internet has given rise to many conspiracies that are hard if not impossible to stop once they are started. Here is one example.
2 thoughts on “The return of the Big Bad Wolf – lessons learned from Vitamin A studies”
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I like reading a post that can make men and women think.
Also, thank you for permitting me to comment!