To Diet, or Not to Diet? Of Tests, Trees, and Forests
Is there really a "best diet" out there?
The Lumberjack World Championships, coming up for those interested in Hayward, Wisconsin in late July, 2015, appear to be very impressive. Contestants are judged on a diverse array of aptitudes, from chopping and sawing, to pole climbing and log rolling. One presumes the criteria for winning each of these are clear and as objective as possible. There is a panel of master lumberjacks to help oversee the judging.
In short, as a non-lumberjack, I am fully prepared to be impressed by the Lumberjack World Championships, and to be convinced that what they say about the best lumberjack is almost certainly true. But I do find an important little splinter of disaffection just the same, or maybe it is merely an observation. The lumberjack competition does not appear to address the possibility that we shouldn’t cut down so many trees. Admittedly, that would be an odd consideration for a lumberjack competition.
Which brings us at last to the real topic du jour, the annual “best diet” competition recently announced at US News & World Report. The results are readily available to you, so I need not belabor those here. Some were likely delighted, and others no doubt disappointed, that the results were highly concordant with recent years. That should come as no surprise, however. The fundamentals of diet, health, and weight control do not change year to year. To the extent that these are stable, one would predict much the same in a diet competition.
The competition does provide for new entries each year, however- a process I know intimately as one of the judges for the past 5 years or so. The editors generally retain all of the contestants from the prior year, and add a new batch based on new studies, new books, or just new traction with the public. All of the new entries are put through the same filters as the repeats, and scored against one another.
Those filters are quite robust, despite the want of logrolling. Diets are judged for scientific support, ease, likelihood of short-term success, likelihood of sustainable success, effects on weight, and various effects on health. For each such category, we judges have a numerical scale to guide our assessment. Our summary assessment is a score aggregated across all of the judging categories.
The editors then take the process an important step further, and aggregate scores for all of us judges. The final rankings in each of the categories and overall thus represent the numerical consensus of 22 judges with diverse expertise. This of course means that the outcomes may or may not align well with the views of any given judge.
So, yes- if you are shopping for a diet, the annual guidance offered by US News & World Report is quite robust. But it, too, leaves a potentially important question unaddressed: should you really be shopping for a diet in the first place?
Shopping for diets prevails in our culture. Partly, this may be because we like competitions in general; from lumberjacks to makeup artists; football players to film stars; singers, dancers, cake makers, and chefs. But in the case of diet, there is something more to this than voyeurism. Hyperendemic obesity and related chronic disease have proven very refractory to our personal and public efforts thus far. Desperation, it seems, breeds gullibility- and probably vice versa, too.
It is, as it has long been, a seller’s market for diets. One need look no further than the annual tally of best-selling books to confirm this. But if some number of thousands of quick-fix, no-effort-required, here’s-your-silver-bullet, just-blame-a-scapegoat diet books have left us with the same weight-related woes we had before, what is the likelihood that the same number of thousands plus one would solve those problems? Very remote, indeed.
But because our culture makes eating well, being active, and thereby controlling weight hard to say the least- we tend to find ourselves a bit desperate. That, in turn, seems to invite a suspension of common sense, and the tendency to overlook the reliable adage: if it sounds too good to be true, it is. Gullible buyers are great for sellers. The sellers, in turn, fan the flames of desperation by making all sorts of just such claims. And so around and around we go, generally getting nowhere.
As my editorial colleagues at US News & World Report know full well, I feel there are some important gaps in our judging criteria. One is the failure to judge practicability at the level of family, or household. I have made the case any number of times that while we may “diet” alone, we “live it” together- and in that in unity, there is strength, and sustainability. Can this “diet” work permanently for a family, whether or not all members have the same health and weight concerns? That question is not included in our assessment, but I think it should be.
Second is the issue of overlap. We are invited to judge diets as they present and peddle themselves to the public. One of the ways to get popular in this space is to assert or imply that there is just one little thing that needs attention, i.e., cut carbs; cut wheat; cut grains; cut gluten; cut sugar; cut meat; add oat bran; drink smoothies; or whatever.
The reality, of course, is that no one scapegoat is making us fat and sick, and no one silver bullet is going to dispatch our dietary demon. Dietary patterns that are truly good are good in a whole lot of ways, and tend to have those traits in common with all other dietary patterns that are also good. So, for instance, a good Mediterranean diet is flexitarian; and plant predominant; and high in monounsaturated fat; and high in fiber; and high in volume; and low glycemic; and so on, and thus confluent with many other contestants in many ways. Still, we are invited to judge each entry as if you can’t have a dietary pattern that embraces the best of each and eat it, too. In fact, you can.
Third, and finally, the diet competition has the same liability as the lumberjack competition, in that it overlooks the fundamental, and even existential question: should we diet at all? Those populations around the world that live the longest and best have a prevailing, cultural dietary pattern that has stood the test of time; they don’t stand in line, as we apparently do, to get the results of a test of competing diets every year. The impressive thing about the reliably “best” diets, for both health and weight control, around the world is that there is no one specific winner. Rather, eating well is a clearly established theme, with allowance for substantial variation. That variation can be at the level of culture, as it is for the world’s Blue Zones, or at the level of household. As long as you stick with the theme, you and your family can enjoy good food and good health. You can love food that loves you back.
There are two good ways to get there from here. One is to acquire the skill set needed to feed yourself and your family well in spite of a culture that makes doing so hard. The other is to change our culture so that losing weight and finding health lie on a path of lesser resistance for us all. You can work on the first; guys like me in public health are working on the second!
The US News & World Report annual best diet assessment is quite well run. As far as I know, the same may be said of the Lumberjack World Championships. We might constructively ask ourselves, though: to diet, or not to diet, in the first place? However good we are at cutting down trees, we also really need to make sure- we can see the forest.
David L. Katz, MD, MPH, FACPM, FACP has very questionable log rolling skills. He does, however, know Hamlet's soliloquy by heart and can generally see the forest through the trees.