For years, I was in the business of disseminating scientific studies on health, careful to caution about the limitations of data and quick to acknowledge how confusing the news media could be when reporting new research.
Now I have hit the ceiling like a Coke bottle full of Mentos.
By now you may have heard or seen that diet soda increases the risk of heart disease. Well, it ain’t necessarily so, and I say that as both a critical reader and a long-time addict, I mean sipper, of Diet Coke. When I switched from six Cokes a day to six Diet Cokes about 25 years ago, my weight immediately dropped 10 pounds. The calorie content is between 0 and 1 per serving. You cannot get fat drinking diet sodas, and obesity is the key factor in heart disease, diabetes, cancer and about everything else except psoriasis.
Now, you could get fat from drinking Diet Coke if you drink it with hamburgers, fries and cinnamon buns. But that isn’t the soda turning you into a blivet.
Read the one-sided American Heart Association news release yourself and then a revised AP account and make you own judgment, but remember two things:
• This is not a clinical trial in which similar groups of people were gathered and some restricted to high-octane soda and an equal number randomly selected to drink only low-octane soda. It is longitudinal study, in which scientists took a group of people with heart disease and went backwards trying to see what they had in common – or not. The conclusion is based on an association, not on cause-and-effect.
• Headlines do not reflect the real truth. And the real truth in this or any other scientific study is that findings are never worth decision-making by themselves. Science is iterative. Data is not the plural of anecdote. The only studies that have any value are evidence reviews, collections of large studies based on randomized trials of the highest statistical validity. Like diet soda itself, this study is pretty weak on fizz.
The basic flaw in media coverage of this study is that the researchers knew that soft drinks had some association not with heart disease but with the precursors of it – the new pharmaceutical industry cluster of symptoms known as “metabolic syndrome.” Why do I bring in Big Pharma? Because if you can convince doctors that the normal processes of living and aging – higher blood pressure, lower good cholesterol and high triglycerides -- are a disease, you can then get them to prescribe "cures" at great profit to the drug lords. None of these metabolic markers are particularly good, but we don’t even know for sure that cholesterol causes heart attacks.
So the research said simply that diet soda may not have a positive effect, but no one ever said it did. The researchers assumed diet sodas would be better for you, but lo and behold there was no difference. Thus, we have a weak associational study hyped by headline writers into “Diet soda is bad for you.”
Well it is bad for your hydration, your teeth and your taste buds, but if we get to pick our poisons, I’d gladly keep my Diet Coke and give up milk – which HAS been implicated in diabetes, obesity, bowel disease, osteoporosis, heart disease, cataracts, colic, ear infections, hyperactivity, and cancer.
The real hazard to health are headlines like this one from a Reuters story appearing on AOL:
Diet Sodas Linked With Health Risks
Consumption Increases Risk for Heart Disease and Diabetes
I don’t know whether the writer who committed this headline works for AOL or Reuters but it is neither new nor accurate.
As yesterday's reporting started being revised to accommodate some of the caveats mentioned here, it was too late. The headlines stuck.
The point here is about the value of print journalism and skepticism versus oxymoronic broadcast journalism and sizzle. In Journalism 202, Introduction to Editing, I taught: "Believe nothing of what you read and only half of what you see." When it comes to health reporting on TV, however, that bromide ought to be reversed.