Health Benefits of Root Vegetables
Root vegetables support human health in a number of ways, with different veggies offering unique benefits (read: the wider the variety we eat, the better!). Root vegetables are any underground plant part consumed as vegetables, though not all of them are “true” roots. Botanically, bulbs like onions, corms like taro, rhizomes like ginger, and tubers like potatoes aren’t actually roots, but in the culinary world, they all count! Even winter squash, which are botanically fruit, are typically included in the root vegetable family because they are nutritionally and culinarily similar.
Root vegetables originate from all around the globe, and were one of the earliest foods consumed by humans. Even today, in many parts of the world, root vegetables are more important as a staple food than grains, especially in West and Central Africa and Oceana. This is due to both their versatility and their ability to store without spoiling for long periods after being harvested. Nutritionally, root vegetables vary in their composition, but due to their role as storage organs (storing nutrients and energy for the rest of the plant), they tend to be nutrient-dense, containing slow-burning carbohydrates and abundant in vitamins, minerals, phytonutrients, and fiber.
A 2019 review of evidence from meta-analyses evaluated the relationship between dietary components and risk of CVD and all-cause mortality. Researchers found that for every 100 grams per day increase in root vegetable intake there was a 24% reduced risk of all-cause mortality. Wow! That’s huge, and in fact, the highest magnitude of benefit compared to all other vegetable and fruit families.
Another 2012 study evaluated data from the European Prospective Investigation into Cancer (EPIC)-InterAct study which looked at the impact of fruit and vegetable intake on the incidence of type 2 diabetes. Comparing highest with lowest quartile of intake, among fruit and vegetable sub-types, only root vegetables were inversely associated with diabetes, demonstrating a 13% reduced risk!
There’s also evidence that root vegetables, especially starchy options like sweet potatoes and parsnips, improve sleep. Our bodies seem primed for slow-burning starchy carbohydrates, such as those found in root veggies, in the evening. We produce more starch-digesting enzymes in the evening, and studies show that eating a decent quantity (say something like 30 grams) of starchy carbs from whole food sources at dinner significantly improves sleep! Fiber intake also improves sleep quality and latency (how long it takes us to fall asleep) in addition to all the other good things fiber does. Root vegetables deliver both!
One of the most important ways that root vegetables benefit us is by supporting the gut health. This is because they contain a variety of carbohydrates that feed beneficial species of bacteria in the gut, including being especially awesome at supporting the growth of two particularly important genera of probiotic bacteria: Bifidobacterium and Lactobacillus. Bifidobacteria carry out a huge number of roles, including producing vitamins, preventing pathogens from colonizing the gut mucosa (including E. coli), protecting against yeast overgrowths, improving the gut barrier function, and reducing endotoxin transport. Likewise, lactobacilli (including the most widely used probiotic, Lactobacillus acidophilus) help inhibit the growth of pathogens such as H. pylori (through a process called “competitive exclusion”), and some species have anti-cancer and anti-diabetic effects. Basically, these bacteria are essential probiotic residents of a healthy gut, so it’s crazy important to make choices that support their growth! And, root veggies are well-proven promoters of these incredible microbes!
Along with containing fiber that enhances the growth of the beneficial bacteria, the prebiotics in root vegetables also enhance the production of short-chain fatty acids (SCFAs). SCFAs (including butyric acid, acetic acid, and propionic acid) are produced from fiber fermentation by specific bacteria groups in the gut. Along with serving as the main food source for intestinal epithelial cells, SCFAs offer an enormous list of benefits for our health, including reducing the risk of inflammatory diseases, protecting against obesity and diabetes, and reducing the risk of heart disease. And, it just so happens that the carbohydrates that get fermented into SCFAs are found abundantly in most root vegetables, such as pectin (high in carrots), fructooligosaccharides (abundant in Jerusalem artichokes, burdock root, chicory root, and yacón), and resistant starch in the form of RS3 (high in cassava and cooked and cooled potatoes).
Overall, root vegetables are absolute rock stars when it comes to our health!
Examples of Root Vegetables
- acorn squash
- bamboo shoot
- beet root
- butternut squash
- cassava (aka tapioca, yuca)
- delicata squash
- Hubbard squash
- Jerusalem artichoke
- kabocha squash
- lotus root
- spaghetti squash
- sweet potato
- tiger nut
- water chestnut
Nutrients in Root Vegetables
Expand to see all scientific references for this article.
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