By Food Revolution Summit speaker David Katz, MD • Originally published on Verywell.com
Just in case you are in a particular hurry today, I will go ahead and give you the punch line right away: the big surprise about the dietary components that matter most to health is that there are no surprises about the dietary components that matter most to your health!
Really. That is, fundamentally, the takeaway message of a study examining diet-related causes of death in the United States, reported in the Journal of the American Medical Association.
Navigating mixed messages
We’ll come back to the study momentarily, but let’s back up a bit. There was a time we were all quite confident we knew a thing or two about diet. For instance, our mothers told us, and their mothers told them, to eat our vegetables and maybe have an apple a day. Maybe we preferred chips and candy, but we weren’t confused about the advice; we knew it was sensible.
These days, though, we seem to specialize in confusion about diet, or at least as I consider it, pseudo-confusion. We all knew that fatty meats weren’t good for us, and suddenly we are told that saturated fat now is, and the more bacon, the better. We all knew that whole grains like oatmeal were good for us, and these days there are whole sub-cultures, and certainly bestselling books, that run on a platform of “grains are public health enemy #1!”
We have been told that generations of scientists have overstated the harms of saturated fat, and obscured the true evils of dietary sugar.
There are competing arguments about the foods and nutrient properties that matter most to health, with various factions clamoring for or against meat, cheese, beans, butter, sugar, gluten, and genetic modification, to name a few.
Even that apple recommended by mom and grandma to keep the doctor away has somehow become controversial.
Fixation on sugar in general and fructose (fruit sugar) in particular has actually caused a sizable portion of the public to start fearing fruit. I was rather stunned that I “needed” to do a New York Times interview in 2013 to make the case that, yes, fruit was still good for us. (Find out an answer to the common question: Can you eat too much fruit?)
We do know how to eat
From my perspective, these distractions and distortions about diet are nothing new; they have been going on, to the sad detriment of public health, for decades. Sometimes they are the product of honest confusion, but more often than not, they are in the service of somebody trying to take advantage of you and sell you something.
We are not clueless about the basic care and feeding of Homosapiens—ourselves—and how odd it would be if we were! After all, we know with considerable confidence that hay is for horses, bamboo is for pandas, tropical fish food is for tropical fish, and as for goats—well, whatever is lying around. Have you ever stopped to think how we could plausibly know so much less about how to feed ourselves well, than we know about how to feed capybaras and echidnas, to say nothing of the more familiar lions, and tigers, and bears?
A visit to a zoo where the animals aren’t all starving is a reminder, every time, that observation and sense can be quite informative. Combine observational sense with science, such as randomized trials, and you have a truly formidable basis to be well informed. That’s just how it is about the best dietary patterns for human health. We have long experience and clear observations, as we have for all other species. We have masses of science too.
And now, we have the study from JAMA, especially timely given all the noise, nonsense, and pseudo-confusion. Using sophisticated analytic techniques, including careful adjustment for other relevant risk factors, data about deaths in the United States, and the best available data about dietary intake, the researchers looked at the associations between sub-optimal dietary intake and mortality.
They found that nearly half of the deaths in our country in 2012 were associated with sub-optimal dietary intake patterns, a finding consistent with prior research going back decades. In particular, death rates from cardiometabolic diseases were most strongly associated with a high intake of sodium, processed meat, and sugary drinks like soda; and a low intake of nuts, seeds, vegetables, fruits, and fish/seafood.
Comparing to our guidelines
Let’s pause there for just a moment to juxtapose these findings with the allegedly “controversial” recommendations in the 2015 Dietary Guidelines Advisory Committee Report, the scientific document that informs the Dietary Guidelines for Americans. That 572-page document explicitly recommended more vegetables, fruits, nuts, seeds, fish and seafood, and less processed meats and sugary beverages. In a word: bullseye!
The strong association between sodium and premature death warrants an additional few words since the ideal intake level of sodium has been hotly debated over recent years. Roughly 80 percent of the salt in our diets is not from our salt shakers at home, but from salt added to packaged and fast food during processing, and added to meals we eat at restaurants. While excess sodium itself may be an important contributor to excess cardiometabolic death, it may also be serving as a marker for a high intake of processed foods, fast foods, and frequent meals eaten outside the home.
7 Guidelines that matter most
There’s a lot more to this study, but that will do for our purposes.
To address the main dietary components influencing cardiometabolic death in the United States and to reduce your own risk:
- Eat less highly processed foods, and especially less processed meat
- Eat less fast food
- Drink less soda
- Eat more nuts and seeds
- Eat more vegetables
- Eat more fruits
- Eat fish and seafood in the place of other meats
Since this study only examined dietary variation in the United States, it couldn’t tell us about every important component of diet. Beans, for instance, figure prominently in the diets of all the world’s healthiest, longest-lived populations. A 2010 study here in the U.S. showed bigger reductions in the risk of heart disease when beans rather than fish were substituted for meat.
My personal recommendation is a diet that emphasizes fresh or minimally processed vegetables, fruits, whole grains, beans, lentils, nuts, seeds, and plain water for thirst.
This new, large, and sophisticated study reassures us all that the dietary components that matter most to health are not the stuff of the latest fad or fashion. They are just what the weight of scientific evidence, common sense, and the global consensus of experts have long told us.