As a former Paleo dieter (for 10 years!), the ideas that grains are nutritionally deficient, meat nutritionally rich, and carbohydrates inherently harmful were deeply engrained in my habits of thinking. So much so that my first forays into eating whole grain bread after learning about plant-based diets were marked by an anxiety that lasted for years–“am I eating carbohydrates instead of fats for an ideological reason, at the expense of my health? Surely these plant-based writers cannot be right?”
Well, certainly the plant-based writers are not right, as I understand now that they could not impartially analyze their way out of a wet paper bag. Still, those days of carb anxiety are long over, as I now understand carbohydrate and fatty acid metabolism to a sufficient degree as to now be inoculated from the Paleo/keto/low-carb/low-fat macronutrient fear-mongering. (When I say “understand”, I mean that I understand how little we know–and how, when popular nutrition writers inveigh against carbohydrates or fats in the diet, they are, to be generous, reading the scientific literature creatively.)
But what had lingered was the sense that, because grains are nutritionally deficient relative to meat, I needed to be especially careful to avoid the nutritional downsides of wheat bread, of which I ate copious quantities.
See for example the bloggings of the major Paleo writers.
So surely whole grains have a well-justified bad reputation?
It is worth noting that neither writer actually explains how the “nutrient density” algorithms determine the rankings that they report. My guess is that, as with much they write, they did not in fact critically analyze the primary sources that they used to make their recommendations but instead used the ready-made listings that agreed with their biases.
That is my guess, in any case, because when I actually looked at the raw data, I saw a different story, which is significantly more complex. This was purely accidental, just the result of playing with Cronometer. Yet what I found shocked me.
For instance, here is the nutritional profile for 2500 calories of whole wheat bagels:
Now here is 2500 calories of lean ribeye, the favored cut of the online so-called carnivore subculture.
All-ribeye diet: severely deficient in 9 nutrients, moderately deficient in 4. All-bagel diet: severely deficient in 6 nutrients, moderately deficient in 1.
In other words, if one could choose between only wheat or meat, and one was aiming at nutrient adequacy, the answer is clearly wheat.
Of course choosing between eating only meat or only wheat would be insane, but the former is, as I said, just what one online subculture has chosen to do. (I am just reporting the facts.) Not a coincidence, Robb Wolf, mentioned above, helped to promote the growth of this subculture.
What happens when one slightly diversifies the plant foods?
2500 calories, half lentils, half wheat bagels:
All-ribeye diet: deficient in 13 nutrients: severely in 9, moderately in 4.
Half-bagel, half lentil diet: deficient in 6 nutrients, severely in 6.
What about reducing wheat and lentils to 43% of total calories each (86% together), putting almonds at 9% of calories (a handful of almonds), and making up the final 5% of calories broccoli and carrots (a handful of each) and sardines (a single sardine, 1.6% of calories)?
I call it the Poverty Omnivore Diet, and it is very nearly my own diet (as an amateur athlete, I add supplemental protein for optimal recovery and muscle mass, and a lot of berries):
Add sunlight, and you are meeting all of your vitamin, mineral, and protein needs in spades.
Again, for comparison, here is an all-ribeye diet:
To provide a further contrast, it is easy to find claims by pseudoscience pushers online that animals are more “nutrient dense” than plants:
That said, a few points are in order.
First, it is sometimes claimed that meat nutrients are more bioavailable than plant nutrients. For a few minerals, this might be true, but I’m not aware of any evidence that this has a meaningful impact on nutrient sufficiency. If readers are aware of such evidence in an otherwise nutrient-rich diet such as the one I have posted, please leave a comment or contact me.
Second, the idea that grain consumption led to worsened health at the beginning of agriculture has led to much speculation that grains per se are suboptimal foods. A paper that reviewed all of the literature on the subject, published in 2011, concluded that stature certainly diminished in most (but not all) human populations during the transition to agriculture. Yet in its discussion, it focused on famine as the likely explanatory factor, not grain intake per se:
Furthermore, if grain consumption and agriculture was the cause of reduced height, then average height would not have increased dramatically over the past few centuries (the Western diet is still heavy in grains):
Finally, if grains replacing meat were the cause of reduced height during agriculture, then vegetarian children wouldn’t be of similar height as omnivorous children. Yet they are.
So why are Paleomyths about meat being more nutrient-rich than plants so widespread, despite the actual story being much more complicated (to say the least)?
My guess is that this is largely motivated by modernity anxiety. For all of human history, humans have idealized and romanticized simpler ways of life, as exemplified by our hunter-gatherer ancestors. We imagine our hunter-gatherer ancestors all ate large quantities of meat. It follows that we should eat meat. We therefore look for sciency-sounding reasons for this belief. Folks like Chris Kresser, Robb Wolf, and Mark Sisson all provide these sciency-sounding reasons. Because this is what we already believed anyway, and we are just looking for reasons to believe it, instead of critically evaluating what these bloggers write, immediately we think “ahhh so that’s why!” We are already primed to believe, not to question. And so we believe. Or at least, once upon a time, I did.
The reality is that the role of plant foods in our ancestors’ diets is substantially more complicated than these writers let on. For instance:
And the rabbit hole goes much deeper. But that is a subject for another post.
Suffice to say, every scientific field is more complicated and richer in controversy than we think at first. Often, we first access a scientific field via a popular writer who tells a good story and appeals to pre-existing beliefs to sell that story. Yet no matter if they are a New York Times bestseller or a famous columnist or respected by large popular audiences on the Internet, we should always be skeptical of the new things we learn, especially if they resonate with and make sense of what we already believe. Unless we are aware of and have critically assessed the relevant body of scientific literature, there is no way whether we are being sold a good yarn or something with strong basis in scientific fact. Until we know better, we need to proceed through life with the assumption that most of what we know is simply a “best guess” based upon “something that we heard that sounded credible”. Because that’s all it really is. My journey through nutrition science, especially with respect to grains, carbohydrates, meat, etc., has taught me that over and over again.
Some people have pointed out that ribeyes should not have carbohydrates. I do not know why the entry at the USDA has ribeyes with carbohydrates. Therefore, I have found a new ribeye entry:
Slightly better than the ribeye I included originally. Still not as good as grains.