In the time that has passed since the Agricultural Revolution first took hold in the Fertile Crescent some 12.000 years ago, the part of the human diet that consists of cereal grains has swelled dramatically. Today, most humans consume significant quantities of wheat, barley, rice, and/or other grains on a daily basis.
Over the same time period, the part of the global ecosystem that consists of humans has also swelled considerably. The fact that this increase coincides with an increased consumption of grains is not a coincidence. Bread, pasta and other stereotypical grain-based foods are fairly energy dense, providing ample calories for survival and reproduction, as well as relatively easy and cheap to produce. Given that this is the case, it’s not that surprising that we’ve ended up in a situation in which we’re now reliant on grains to feed the world. We can’t all eat a grain-free diet, at least not one that’s composed exclusively of wild plants and animal foods, like the one our hunter-gatherer forebears took in.
If it were healthy to eat a grain-based diet, this wouldn’t have been a problem. Unfortunately though, this isn’t the case. Grain is to humans what cheap fodder is to livestock. It fills us up, but it doesn’t truly nourish us. It’s inferior to the foods that our preagricultural ancestors foraged in the wild. This is not to say that all grain-based foods are equally bad or that nobody can benefit from eating grains; however, in general, it’s safe to say that most people could benefit from replacing some of the grains they are eating with other foods.
What’s the best alternative to grains?
This natural question that follows from the above paragraphs is: What types of foods should we replace grain-based foods such as bread and pasta with?
One option is to bring more animal source foods such as eggs, meat, and fish into our diet. That may certainly work in some instances; however, it’s not a completely satisfactory solution, in part because it’s not ideal from an environmental point of view. Also, there’s a limit to how much protein one really needs. There’s no point in taking in more protein than one desires.
Another option is to replace grains with fatty plant foods such as avocados, seeds, and nuts. That’s a great option, but again, it’s not a completely satisfactory solution, as there’s a limit to how much of these foods it’s healthy and enjoyable to take in.
A third option is to replace grains with other plant foods that are healthier for us, but that still provide a fair amount of energy that our bodies can use. Leafy vegetables don’t fit the bill, as they are very low in calories. Legumes arguably also fall short. They aren’t too low in calories; however, they have certain nutritional characteristics that arguably make them less than optimal for human consumption – an important caveat being that not all legumes are equally problematic. Fruit is not a satisfactory alternative either, as it’s not a good idea to take in massive quantities of fruit every day, particularly not the very sugary kind.
A better solution, as I see it, is to replace grains with root vegetables.
Root vegetables have been – and continue to be – an important part of many traditional diets
Many traditional, non-westernized populations are known to consume significant quantities of root vegetables (1, 2, 3). This includes hunter-gatherers who reside in Africa, a part of the world where much of human evolution took place, such as the Hadza hunter-gatherers of Tanzania, who eat quite a lot of tubers – swollen underground stems or roots of plants from which new plants can grow. There’s no reason to think that the situation was any different in ancient times (1, 2, 3, 4), although one needs to account for the fact that some root vegetables are difficult or impossible to digest in their raw state and therefore needs to be heated in order to be accessed by human digestive enzymes.
We obviously don’t have the option of regularly eating the extremely fiber-rich tubers that the Hadza take in – or any of the other wild plant foods that hunter-gatherers forage for that matter. Most of us do have access to root vegetables that are of fairly high quality though. In particular tubers and roots grown by small, organic producers tend to be great.
What makes root vegetables superior to grains
The fact that root vegetables, including tubers, corms, and bulbs, have been a part of the human dietary repertoire for a very long time, whereas grains only became a part of the human diet quite recently, suggests that we’re better adapted to eating the former than the latter. A large body of evidence supports this notion.
The first thing that’s important to recognize is that grains are extremely rich in carbohydrate. They have a higher energy density and contain a lot more starch than the plant foods that were routinely consumed throughout human evolution. When compared with for example rice, root vegetables such as carrots, turnips, and beets are fairly low in energy and carbohydrate. This is particularly beneficial in the context of obesity prevention and treatment. (Note: Some cultivars, such as yams and potatoes – both white and sweet – are quite starchy and should be restricted/eaten in accordance with one’s health status and activity level.)
Second, grains contain an assortment of antinutrients and proteins that have been implicated in a variety of health disorders, including autoimmune diseases and mental illness (5, 6, 7, 8). Third, when compared with grains, vegetables contain more cholesterol-lowering soluble fiber, as a percentage of total fiber. Last but not least, the micronutrient profile of root vegetables is superior to that of grains (9).
This is not to say that everyone would benefit from taking all grain-based foods out of their diet. Some people, for instance some hard-training athletes and certain sick individuals, have special nutritional requirements and may benefit from consuming grains. In general though, it’s safe to say that it’s healthier to base one’s diet around vegetables than around grains. Root vegetables may tax one’s wallet and time somewhat more than grains, in the sense that they tend to be more expensive, on a calorie-by-calorie basis, and often demand more time spent in the kitchen (I recommend boiling or otherwise heating most root vegetables, as opposed to eating them raw); but that’s arguably worth the investment.
Grains are heavily embedded into our modern culture. A lot of people are used to eating grains every day and find it difficult to comprehend what they could possible eat instead. Moreover, grain-free diets have a reputation within certain circles as being unsustainable and hazardous to the environment. This notion is largely rooted in the belief that such diets are high in meat. This isn’t necessarily the case though. The fact that a diet contains little or no grains obviously doesn’t have to mean that it’s very high in animal source foods. It’s certainly possible to eat other plant foods in lieu of grains.
Besides the nutritional aspect, root vegetables have several more things working for them. They can be grown in many parts of the world and stored for fairly long periods of time. Also, it’s my understanding that large-scale production of roots and tubers is fairly non-taxing with respects to its impact on the environment, at least when compared with the industrial production of meat.
Whether or not it would be feasible to replace grains with root vegetables on an international or even global level is an open question that demands inquiry. In certain parts of the world, the problem is “simply” that there isn’t enough food to feed everyone. In those parts, the health risks associated with the consumption of grains and processed foods obviously have to take a back seat to other, more pressing issues related to undernutrition and starvation.
However, in many other parts of the world, such as in the U.S. and Scandinavia, the problem isn’t a lack of food, but rather that people aren’t making the healthiest choices when they’re in the supermarket. If the consumers in those parts of the world were to alter their consumption pattern, the food production system would adjust accordingly.