The trouble with research in the medical sciences is that much initial work is based on correlations and it is often hard to pin down definitively the causal relations between them. This can lead to health recommendations that later get nullified or even reversed when some hitherto unsuspected third factor is discovered to play a role in creating the correlation. This problem is especially prevalent when it comes to preventive health treatments designed to head off some future problem, where reversals of recommendations can happen frequently. This can be very disconcerting for health-conscious people who may well feel confused by the conflicting advice.
The most obvious example is with weight. Hardly a day goes by that we do not hear of some factor that supposedly causes weight gain or can help in weight loss, quickly followed by diets based on those findings, only to have those finding challenged and refuted soon after. This is exacerbated by people like the infamous Dr. Mehmet Oz who uses his popular TV program to hype all manner of fad diets and miracle weight loss pills that have little science to back them up. When they are found to not work, this can be very discouraging for those seeking to lose weight.
We also had the myth that gained widespread traction (partly fueled by the bottled-water industry) that one needed to drink eight glasses of water a day to keep the body healthy. At one point, I too decided that I should do this but found it hard to keep up and gave it up. Later that recommendation turned out to be based on no science at all. The new recommendation is to drink when one is thirsty, which is what I had been doing all my life.
In general, I tend to be wary of recommendations that are supposed to stave off some problem in the future if there is no sign of any problem now. This sometimes requires me to ignore my doctor’s well-meaning recommendations. For example, it was recommended that I take the drug Fosomax to build up bone density since tests showed that I had slightly lower density than was optimal and he wanted to prevent future broken bones. But I decided to not do so. A few years later new tests showed that not only had my density not decreased, it had actually increased by itself. Not only that, new studies suggested that long term use of Fosomax had adverse effects and may actually increase the chances of bone fractures.
I did a similar thing with the recommendation to take Vitamin D supplements as a preventive measure, since mine was a little low compared to the norms. I again ignored my doctor’s suggestions, partly because dark-skinned people tend to have low Vitamin D and it was not clear to me that norms developed in the western world with light-skinned people should be applied universally. Now a new study comes out that says that such supplements are not effective.
I also tend, when I have a fever or headaches or other pains, to avoid doing anything and wait for it to go away by itself, unless the discomfort is acute at which point I take the absolutely minimum amount of aspirin or Tylenol to ease discomfort. The recent studies that too much use of Tylenol can be dangerous suggested that my minimal approach helped to avoid that problem.
Of course one should take medical research seriously. And nothing beats science-based medicine to treat actual ailments. But I am wary of taking large doses of even benign-sounding things that are meant to prevent things from happening in the future, if there are no serious indications that I have symptoms now or am highly prone to getting it.
In general my attitude is to simply do things in moderation and have a balanced diet. Of course, I also have to be wary of falling into the trap of confirmation bias, where I only pay attention to research that supports my minimalist attitude to preventive treatments. It could well be that I am just having a lucky streak and that one day I will suddenly keel over dead because I ignored some good advice. Then my doctor will have the pleasure of saying “I told you so!”
But that’s the trade-off I have chosen to make.