I admit that, as I write this, it is hard to think of anything else as important when Vladimir Putin has invaded Ukraine in an action that, in addition to its obvious direct impact on that country, had led to as great a threat to nuclear war and human extinction as we have seen in two generations. That a deranged power-mad autocrat can do this is even more terrifying when we look at the number of psycho autocrats that have gained power in the world, including recently (and hopefully not in the future) in the US. But I am not going to write about it, for three reasons:
--It is not the topic of this blog, which is Medicine and Social Justice
--There remain a lot of things that urgently need discussion in regard to American healthcare, mired as it is not only in the evils of for-profit capitalism but incredible inefficiency and incompetence, and
--These issues actually matter on a day-to-day, week-to-week, year-to-year basis for the American people.
First, I will start a good thing, or at least a mixed one. The less-good part is that Jane Brody, the health columnist in the New York Times, has written her last column. The good part is lauding her for the incredible contributions she has made to our understanding of the issues of our health over the decades (since 1976) that she has been writing it. We all have (or should have) learned much from her, about diet, and exercise, and dealing with illness and even death. In her last column she points out some areas where her advice has been incorrect, based on the science of the time, when new evidence has disproven it. I believe that an ability to acknowledge that you were wrong, whether because (as usually true for her) the scientific knowledge has changed, or because you wanted to believe something and so were previously unwilling to actually examine the evidence adequately. A particular area of health that she has been associated with is diet (she has written several cookbooks), and this is the area in which her admission of error is most incomplete and thus disappointing. While she notes that ‘One of the most significant shifts has concerned dietary fats,’ her emphasis is on how the recommendations in the ‘70s to shift away from animal fats missed the dangers of vegetable-based trans fats. She cautiously says ‘But time will tell whether specific dietary fats, or the much vaunted Mediterranean diet currently embraced by many doctors, will fall prey to future findings.’
But that’s it. There is no mention whatever of the problems
with carbohydrates in the diet, particularly simple carbohydrates like sugars, on
people’s health. This is a major lapse. Without getting into a discussion about
the benefits of a very-low-overall carbohydrate diet (e.g., Atkins, paleo,
etc.), there can be no question that large amounts of sugar (and possibly even
small amounts of sugar) in the diet is deleterious, non-nutritious, and causes
not only obesity but a great many other health problems, and that no reasonable
diet today can fail to feature this fact. Moreover, it completely avoids the
evidence that the campaign against dietary fat, carried on by organizations
such as the American Dietetic Association (now the Academy of Dietetic and
Nutrition, AND) and many others, for decades was funded by the sugar industry
and the manufacturers of high-sugar foods such as soda pop (addressed in
several blog posts, including Gangster
capitalism and our health: In the US and in the World Jan1, 2019, The
AAFP, Coca-Cola, and Ethics: Serving the public interest? Aug 20, 2010, and
others). The lack of any mention of this in Ms. Brody’s column is concerning;
does she still believe that fat is a bigger dietary problem that sugar? This is
not an academic question; go to your grocery store and look at the labels on “low
fat” or “fat free” products and see what is in them. My personal favorite is “fat-free
half-and-half”, which is almost an oxymoron because fat is the basis of half-and-half:
half whole milk (4% fat) and half cream (about 20%) for a total of about 12%.
How can half-and-half be fat free? Read the label! It is full of sugars.
Indeed, almost all foods with such labels are high in calories an high in carbohydrates,
especially sugar (commonly in the form of ‘high-fructose corn syrup’).
Another undying health claim, promoted by some doctors and many non-medical professionals and non-scientists for several decades is vitamin D (not an issue which Ms. Brody, in this final column, addresses). Fifteen years ago, endocrinologists were promoting vitamin D deficiency as a major endemic problem, claiming deficiency at blood levels then (and now) considered normal. While most have backed away from the idea that it is a panacea, some have not and fed an ongoing commitment to taking more of this vitamin, an idea that flourishes on, of course, the Internet. With the onset of the COVID-19 pandemic, enthusiasts have found this to be the newest “indication” for it (Vitamin D, false nostrums, and conspiracy theories: The world has enough real problems, Jan 28, 2021). In an excellent – and brief and easy to read --Commentary on Medscape® (Feb 17, 2022), John Mandrola asks ‘Why Is Vitamin D Hype So Impervious to Evidence?’. His emphasis is on critical appraisal of the scientific research, on the quality, breadth, and significance of the studies done. He emphasizes that there are many, many randomized controlled trials that do not show that taking Vitamin D decreases the risk of any condition (other than true vitamin D deficiency, which occurs at quite low levels.) Among the many important points he makes is that association (many people with chronic disease have lower vitamin D levels) does not show causation (it was the low vitamin D levels that caused the disease), because often ill-health causes the lower levels, and still less that administration of vitamin D will cure it. Indeed, he discusses the many large, well-designed studies that prove that it does not.
So why is this issue so impervious to evidence? The answer, it appears, is rooted more in psychology than science, in how people choose to believe what they believe and seek out evidence that supports it (if, indeed, they seek evidence at all). There are always experts who espouse their (and almost any) position. Even when they are a small minority, there are 330 million Americans and 8 billion people in the world, so a small minority can be a lot of people. Almost all people (scientists are a very small minority) do not have the training or the skill to read and assess the scientific literature, and it is uncommon that they even try. Instead, they seek (or have sent to them) articles by people that seem to be reputable that support their position. Mandrola focuses also on how even scientific papers engage in “spin”, pointing out how often they emphasize minor, secondary, and non-significant results even when the main point that they were trying to prove (that vitamin D cures or prevents something) is not shown by their research. Indeed, such minor things are pounced on by a public that wants to see what isn’t there; he gives this example:
the authors of the VITAL trial, which found that vitamin D supplements had no effect on the primary endpoint of invasive cancer or cardiovascular disease, published a secondary analysis of the trial looking at a different endpoint: a composite incidence of metastatic and fatal invasive total cancer. They reported a 0.4% lower rate for the vitamin D group, a difference that barely made statistical significance at a P value of .04.
But everyone [he says; I think he means physicians and scientists] knows the dangers of reanalyzing data with a new endpoint after you have seen the data. What's more, even if this were a reasonable post hoc analysis, the results are neither clinically meaningful nor statistically robust. Yet the fatally flawed paper has been viewed 60,000 times and picked up by 48 news outlets. [emphasis mine].
Think about that. It is not what is proven to be true that gets the most coverage, it is what is most provocative. And clearly, this is not just about vitamin D. COVID and the COVID vaccines are common and prevalent examples of people choosing to believe something and then picking and choosing research that supports it; they even call this “doing their own research”. Some of this is the result of religious-like devotion to a position or point of view, some is purposely malicious, some is conspiracy theory, and some is honestly being overwhelmed by data that they do not understand. But it sure can be very dangerous. You deciding that COVID is not a risk anymore (if ever) and you don’t need to be vaccinated and don’t need to wear a mask is dangerous to me!
If over 95% of climate scientists agree that human activity, especially the burning of fossil fuels, is the cause of global warming, but many people do not believe it, why would we think the kinds of foods we eat, the benefits (or not) of taking high doses of a vitamin, the risk of a pandemic virus, the benefit of vaccination, would not be controversial? I would like to agree with Dr. Mandrola that there is hope, but I am sometimes not sure.
In the meantime, get vaccinated, eat very little sugar, and do not overdose on vitamin D, which can absolutely happen.
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