Are antioxidants safe to take for osteoarthritis?
I recently wrote a blog about a new prescription medication on the market called Limbrel (flavocoxid). The medication is called a prescription "medical food" that contains high potency antioxidants that are typically found in fruits, vegetables, and other foods. In addition to being full of antioxidants, Limbrel acts as an anti-inflammatory agent by blocking enzymes that promote inflammation.
In response to my blog, Rand posted a comment that said: Haven't we just been warned not to take antioxidant supplements because they may contribute to cancer?!?!
I can appreciate where Rand is coming from and wanted to take the time to write a blog in response. There is a lot of information and misinformation out there and it can get pretty confusing. When I was in medical school, I used to come home and tell my parents what they should be eating, shouldn't be eating, and what supplements they should be taking. They would sometimes laugh and say, "Today broccoli fights cancer, tomorrow they will tell us it causes it!" My dad would add, "Do everything in moderation and you'll be all right."
In many ways, my parents were right. Research is constantly coming out regarding nutrition and supplements. The latest and greatest fad diet or supplement today may turn out to be tomorrow's health concern. Any single study has to be viewed critically and with some skepticism. You always would like to see confirmatory studies, and then more studies confirming the previous studies until a body of evidence develops that demonstrates a medication's or supplement's safety and efficacy.
When I started medical school, research seemed to suggest that vitamin E supplements could prevent heart disease. I remember the buzz in school was that it may even help all sorts of diseases. However, just four years later, by the time I left school, it was believed that vitamin E may actually increase the risk of heart disease in some patients. Confusing, indeed!
Of course, we all have the same goal. We want to understand the body; what makes the body function better, keeps it from becoming sick, and heals it when it is sick. Research to further this purpose is not always neat and clean. It is rare indeed that one research study in medicine changes the way that we practice. This is particularly true with nutritional studies - which, on the whole, tend to have more methodological problems than some other studies. For this reason, again, you want to see studies with few methodological problems confirming one another until a body of research is available to analyze. While there are certainly exceptions, it is important to remember that one study in isolation can sometimes be misleading. Unless the study has excellent methodology, confirmatory studies are almost always needed before firm conclusions can be drawn.
So -- is it safe to take antioxidants for osteoarthritis? According to the National Cancer Institute: "Considerable laboratory evidence from chemical, cell culture, and animal studies indicates that antioxidants may slow or possibly prevent the development of cancer. However, information from recent clinical trials is less clear. In recent years, large-scale, randomized clinical trials reached inconsistent conclusions."