Preventive Medicine Column

Dr. David L. Katz

As you may know, US News & World Report released a list of “best diets” ( to coincide with the annual bumper crop of weight loss resolutions as the New Year begins.  I was privileged to be one of the 22 judges.

I get the sense we agreed more than we disagreed, and am fairly comfortable with most of the outcomes.  We based our judgments of each of 25 diets in 7 different categories on published papers, on-line materials, and personal clinical experience.

The results were an endorsement of balanced, sensible approaches to weight control.  No diet based on a gimmick, or on wild distortions of a healthful dietary pattern scored well.  Those diets that did score well were generally conducive both to losing weight, and finding health.  Big winners included Weight Watches, which came in first for both weight loss and ease; and DASH, a diet developed at the NIH for blood pressure control and since shown to confer other health benefits.  The Mediterranean diet, and the low-fat, plant-based diet developed by my friend Dean Ornish, placed highly as well.

However, different diets did come in first for health, weight loss, diabetes, and heart disease- and personally, I find that a bit silly. Weight loss, by healthy means, is among the most important ways of reducing risk for diabetes and heart disease.  A diet that reduces diabetes risk reduces heart disease risk.  A diet that reduces risk of heart disease and/or diabetes, two of the leading public health perils of our time, is obviously good for health.  A diet cannot be good for health unless it reduces the risk of heart disease and diabetes. 

I trust you see where this logic leads.  A good diet is a good diet, period.

But is there a ‘best’ diet?

I have weighed in on that topic (, and basically said- no. We have abundant evidence to support a basic theme of healthful eating, and almost none to say which of the several reasonable contenders (Asian, vegan, Mediterranean, etc.) is truly best.

That’s good, because it means we do have an evidence-based theme of healthful eating- conducive to weight control- and variations on that theme allowing for customization and the indulgence of your personal preferences and priorities. 

But let’s be clear, there IS a theme- and though you are the boss, you abandon the theme at your potential peril.  The fundamentals of the theme were pithily captured by Michael Pollan with: “eat food, not too much, mostly plants.”

Eating food means real food.  Pronounceable food.  If it glows in the dark, you probably shouldn’t eat it.  The longer the shelf life of the product, the shorter the shelf life of the person eating the product.

“Not too much” might seem like hard advice to take, but quality control provides for quantity control.  Many processed foods are of the “betcha’ can’t eat just one” variety.  Wholesome foods- an apple, for instance- are of the “betcha’ won’t eat than one” variety.  In fact, I’ve recently learned of a Mom who lost 115 lbs due almost entirely to use of the NuVal ( system in her supermarket, and simply trading up to  more nutritious choices in each aisle.  By addressing quality, quantity and weight mostly took care of themselves.

Mostly plants is pretty straight-forward.  An emphasis on plant foods is evident in almost diets associated with both weight control and health, and is, into the bargain, important for the health of the planet.

I am a proponent of Weight Watchers; their programming clearly works for weight loss, is sensibly aligned with healthful eating, and provides the structural support many people need.  I believe, however, we can do even better- building skill power systematically to facilitate lifelong health and weight control, while addressing the needs of all family members at once.   A program I have helped develop, Weigh Forward, is an example.  I also see opportunities for customizing variations on the theme of weight control based on genetic testing. 

As we size up best diets at the start of a new year, we can celebrate the winners- but note that too many of us are still losing.  A majority of adults in the US are overweight or obese.  Our best efforts to date are not yet good enough.

What would truly be best is modifying the world- so that eating well and being active simply prevailed.  While waiting for that change- or better, while working for it- the best diet is bounded by considerations of not just losing weight, but finding health; not just you, but your family; not just now, but lifelong.  Stay within the bounds of the theme, and shop the variations to find your best way forward in the New Year.




Dr. David L. Katz;