I think that, when it can, scientific research should answer important practical questions, and I think it’s reasonable to ask that this be done with some degree of rationality and thoroughness.
The scientific literature on diet and health shows how large the failures can be. I think we can do much better.
Diet, heath, and the void
Here’s an important question:
How can someone choose a diet that lowers the risk of early, slow, and horrible death?
This general, practical question leads to many specific, scientific questions about messy real-world causality, and some of these can be answered.
The answers are almost irrelevant to basic science (they fit in the lower left quadrant of the table in my previous post), but they are vitally important to human health.
Here’s what I find striking and disturbing:
- Standard research methods can answer many of these questions.
- No one did the work that would have answered these questions.
- The system hasn’t changed, and I see no real effort to change it.
The scandal of the science of dietary fats
For example, consider the question of cardiovascular disease and isocaloric substitutions among saturated fats, polyunsaturated fats, and carbohydrates.
And the answers? Saturated fats have long been known to be deadly, so surely there is unequivocal science that shows… What’s that? — Shows nothing of the kind?
Here’s the title and abstract of a representative 2010 analysis of the literature to date:
Effects on Coronary Heart Disease of Increasing Polyunsaturated Fat in Place of Saturated Fat: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Reduced saturated fat (SFA) consumption is recommended to reduce coronary heart disease (CHD), but there is an absence of strong supporting evidence from randomized controlled trials (RCTs) of clinical CHD events and few guidelines focus on any specific replacement nutrient….
This study finds that replacing substantial amounts of SFAs with polyunsaturated fatty acids — but not carbohydrates — reduces cardiovascular disease mortality, but that this is almost precisely offset by increases in non-cardiovascular-disease mortality. Another meta-analysis suggests that switching from SFAs to carbohydrates increases the risk of coronary deaths. [17 June: Updated to correct confused references.]
These evaluations of the scientific literature are not outliers.
A huge warning flag about the way we do science
For decades, questions of diet and health have been among the most prominent scientific questions in the world, with millions of lives at stake. For decades, billions of dollars have been spent by foundations and public agencies on health-branded research, presumably in the public interest. And for decades, basic questions regarding diet and health have been unanswered, or worse, answered by studies so poorly conceived that they led to the wrong conclusions.
More billions of dollars — and priceless public attention and life-changing effort — were poured into promoting and responding to advice based on this needlessly inadequate science.
Obvious questions, obvious importance, accessible answers, a failure to respond in a remotely rational way.
For better results, repair institutions
What might be done to help correct this? Here’s a broad brush-stroke suggestion for avoiding huge gaps in science done in the public interest:
- Obligate science funding agencies to establish institutional mechanisms that are responsible for registering (allegedly) open scientific questions, and from diverse, external sources.
- Make it embarrassing for the responsible parties to ignore questions that obviously shouldn’t be ignored.
- For each question worth attention, require that they state an explicit estimate of the importance and difficulty of answering it.
- Obligate the agency to either fund research on the most important and answerable questions, or to explicitly state reasons for neglecting them.
It think that institutions along these lines would cause a perceptible shift toward rational priorities. There are many potential implementations. The financial cost would be negligible. It would be great sport
I urge reformers to ask a simple question: If practices along these lines had been in place for the last 20 years, wouldn’t we be better off? Looking forward, how much would this be worth?
{ 8 comments… read them below or add one }
Criticism of one of those papers here:
http://wholehealthsource.blogspot.com/2010/03/leave-your-brain-at-door.html
sr, that criticism only strengthens the argument posted here. (Wholehealthsource is my favorite diet-and-health blog, by the way.)
Years of quality life are what I think we care about. That might be hard to measure, but time in hospitals, convalescent homes, and perhaps in home nursing care might not be. So I would like to see U.S. life expectancy data adjusted for these.
Also, the “2010 analysis” and “Another meta-analysis” links seem to point to the same paper.
I’m dumbfounded by the lack of critical thinking in nutritional science, especially in the face of contradictory epidemiological studies. It’s one thing to be a lazy scientist in physics or zoology, someplace where negligence doesn’t directly affect people’s health, but in medical and nutritional science, this sort of negligence almost borders on the criminal.
I’ll likely be entering academia soon, and I’ll do my best to promote reform. Unfortunately my field (math) is far from the epicenter of where this reform is most needed.
@ Carl Lumma — Thanks for noting the problem with the links (now fixed).
@ Jordan Fisher —
When a professional, trusted, and publicly funded research community performs this poorly— offering or supporting advice responsible for uncounted early deaths — it’s hard to argue that jolly acceptance is the right response.
There’s negligence, but there’s little or no value in pointing fingers at individuals. The failure and responsibility is diffused over an entire field. It’s institutional.
If institutional shortcomings were people, action would be much easier. With a face behind the wrong, the human instinct to punish wrongdoers could be channeled into an angry campaign to obliterate the vile institutional shortcomings…(still a problem here)…by deploying the weapon of gentle, considered, and constructive institutional innovation.
Speaking of needless megadeaths, how about using blood pharming to refil old folks?
http://www.dailymail.co.uk/sciencetech/article-123361/Scientists-develope-fake-genetically-engineered-blood-use-battlefield.html.
Blood doping has some short-term value for sports., and I’d like to see Baby Boomers serve as the medical experimentation dummies before their pig is excreted from the demographic python.