Lying To The Lab Coats

We’ve all read reports on medical studies that have reached significant conclusions about the consequences of certain behavior or the causes of physical or mental conditions. One question about those studies always lingers: if one of the elements of the study is self-reporting by participants, how do we know that the participants are really being truthful in what they are reporting — or, whether they are lying to the lab coats instead?

A recent discovery of misreporting by participants in a genetic study of the effects of alcohol consumption highlights the concern. Researchers determined that participants in the UK Biobank that provided the data for the study often underreported their use of alcohol and did not provide accurate information about their consumption over time. (The UK Biobank includes data from 500,000 volunteers who have, since 2006, agreed to be periodically questioned and tested about various activities and conditions.)

Even worse, the false information caused the researchers in the genetic study to reach inaccurate conclusions about alcohol use and its association with certain health conditions. When statistical analysis techniques were used to scrub the Biobank data of false information, for example, negative correlations between alcohol consumption and diseases like anemia, hypertension, and type II diabetes were significantly reduced — in some cases to near zero.

It’s not clear from the article linked above precisely how the researchers discovered the underreporting, but the fact that study participants lied to the lab coats about their use of alcohol shouldn’t surprise anyone. Human nature tells us to be dubious of the scrupulous accuracy of self-reported information on any potentially embarrassing topic — whether it’s smoking, drinking, daily exercise, amount of TV viewing, or consumption of ice cream and potato chips. The next time you read about a study that reached startling conclusions about something, take a look at how the data was generated, and if self-reporting was involved, consider whether the nature of the study might have tempted participants to fudge a bit in their reporting. And let’s hope the lab coats do likewise.

The Value Of Vitamins

This week the Annals of Internal Medicine published an editorial about the growing use of vitamin supplements in America that may come as a surprise to many Americans.

Entitled Enough is Enough:  Stop Wasting Money on Vitamins and Mineral Supplements, the strongly worded editorial summarizes three articles and the results of a number of large scale studies that produced “sobering evidence of no benefit or possible harm.”  The editorial’s concluding paragraph states:  “In conclusion, B-carotene, vitamin E, and possibly high doses of vitamin A supplements are harmful.  Other antioxidants, folic acid and B vitamins, and multivitamin and mineral supplements are ineffective for preventing mortality or morbidity due to major chronic diseases.”

America has become a nation of pill-poppers.  About half of Americans take some kind of dietary supplement, and Americans spend $12 billion a year on vitamins alone and $30 billion for all dietary supplements.  The notion that the vitamin supplements Americans are swallowing in record numbers are ineffective — or even harmful — may shock people. Of course, whether Americans learn of the editorial and the results of the studies, and then whether they stop taking the vitamins and dietary supplements, is anybody’s guess; one vitamin user interviewed by CBS said she would keep slugging down the pills anyway.

Why are Americans so committed to vitamins and supplements?  Some people blame the aggressive marketing of the products, but I think the root cause lies in two other factors.  First, for years Americans have been bombarded with stories about studies that conclude that something is good or bad — be it cyclamates, red dye #2, or something else.  These studies, I think, have conditioned people to believe that taking one substance, or avoiding another, could have significant health benefits.  If a “medical study” shows that avoiding something has a material effect on health, why is it so outlandish to believe that taking another substance — or a combination of substances — might have a similar beneficial effect?  The context created by the onslaught of “medical studies” establishes fertile ground for hawking vitamins and supplements.

Second, people clearly hope that a magic little pill or two can make up for their lack of exercise, poor diet, or other questionable lifestyle choices.  Like Fox Mulder on The X-Files, they want to believe — but unlike Mulder, they lack any true skepticism.  If they skip a walk and eat a quart of ice cream but take a vitamin or “fat-burning” concoction, they can rationalize that they are doing something positive about their health.  They simply don’t want to get the advice offered by one of the authors of the Annals of Internal Medicine articles:  “fruits, vegetables, nuts, beans, low fat dairy, things like that ..exercising would probably be a better use of the money.”

And that’s probably why the Annals of Internal Medicine editorial won’t have much impact.  Believers believe, and hard advice and facts usually don’t get in the way.