For many people, the terms “beans” and “grains” are used interchangeably. This is understandable, since both are plant foods that come in seed form and are staple ingredients in many cuisines. However, beans and grains are completely different food groups with distinct origins and nutritional profiles. Read on to learn why beans are not grains at all.
The Botanical Difference
Botanically speaking, true grains are the seeds from grasses in the Poaceae family This includes wheat, rice, oats, rye, barley, millet, sorghum, and corn Meanwhile, beans belong to the Fabaceae family of flowering plants.
This means that grains and beans develop from entirely different species of plants. Beans sprout from a pod attached to the parent plant, whereas grains grow from hollow stems protected by leaf sheaths.
So while they both provide edible seeds, grains and beans have distinct structures and growing methods This key biological difference sets them apart definitively
Types of Beans vs. Grains
There are thousands of edible plant species in the world. Here are some of the most common varieties of beans versus grains:
Beans
- Kidney beans
- Pinto beans
- Black beans
- Garbanzo beans (chickpeas)
- Soybeans
- Lentils
- Peas
Grains
- Wheat
- Rice
- Corn
- Oats
- Rye
- Barley
- Millet
- Sorghum
As you can see, there is no overlap between the lists. Botanically, beans and grains occupy completely separate categories.
Culinary Uses
Culturally, beans and grains are used quite differently in cooking as well.
Beans are prepared in dishes like:
- Chili
- Tacos
- Rice and beans
- Hummus
- Bean soups and stews
Meanwhile, grains are used to make:
- Breads
- Pastas
- Cereals
- Flours
- Baked goods
- Porridges
So beans and grains generally play different culinary roles based on their textures and flavors. Of course there are exceptions, but their typical uses vary.
Nutritional Profile
When looking at the nutritional makeup of beans versus grains, several differences stand out:
Beans
- High in fiber
- High in protein
- Low glycemic index
- Rich in folate, iron, potassium, magnesium
Grains
- High in carbohydrates
- Moderate in protein
- Contains gluten (wheat, rye, barley)
- Rich in manganese, selenium, phosphorus
Beans offer more protein and fiber compared to grains. They also have a lower glycemic index, meaning they won’t spike your blood sugar as dramatically.
Meanwhile, grains excel at providing carbohydrates and certain minerals like manganese and selenium.
So while both provide useful nutrition, their precise nutritional offerings vary.
The Bottom Line
Beans and grains may seem interchangeable to the average person, but scientifically they are completely different.
Key takeaways:
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Beans are seeds from legumes, grains are seeds from grasses.
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They come from distinct plant families with different structures.
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Common bean and grain varieties do not overlap.
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Beans and grains play different culinary roles.
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Their nutritional profiles show more contrasts than similarities.
So beans are definitively not grains. They have unique origins, food uses, and health benefits compared to true cereal grains. Both can be part of a healthy diet, but understanding their differences is important too.
Next time you enjoy a bowl of rice and beans, you can appreciate just how botanically distinct these two plant foods actually are!
How to reduce the lectin content of foods
Putting foods in water ahead of time and then boiling them for 15 minutes will get rid of most lectins. Since dry heat (like baking or roasting) doesn’t work as well as long-term boiling, baked goods made with bean or grain flours aren’t as safe as boiled goods. Dry roasting only removes about 75% of the lectins from raw peanuts. Toasted wheat germ contains active lectins, as well. Lectins laugh at stomach acid, and many lectins resist digestion by our intestinal enzymes. Because of lectins, grains and beans should never be eaten raw (kidney bean lectin is very poisonous if eaten raw or undercooked; it will make you throw up a lot).
There are fewer lectins after sprouting, but they’re still there. This is because as the seed germinates and turns into a baby plant, a lot of the lectin protein is broken down to feed the growing seedling. However, some lectins remain to protect the growing plant.
As a result, there are only two real ways to stay safe around lectins: boil them for a long time or stay away from them.
There are many different types of lectins, with different carbohydrate targets, attack strategies, and potencies. Some of the food lectins that have been studied the most are peanut lectin, kidney bean lectin, soybean lectin, potato lectin, and tomato lectin. In the future I will be writing more about these foods and their specific lectins.
Gluten is not a single protein; there are hundreds of proteins in the gluten family. Glutens are proteins found only in the following grains:
- Wheat (bulgur, durum, farina, graham, kamut, matzah, seitan, semolina, spelt)
- Barley (malt)
- Rye
- Triticale
[Oat crops are often rotated or milled with wheat products, so oats are sometimes cross-contaminated with wheat glutens.]
Glutens are just proteins that are stored in seeds. They feed the plant embryo when it’s time for it to sprout. Sounds innocent enough . Still, glutens are known to cause both Celiac disease and gluten sensitivity. Celiac disease is a serious autoimmune disease that affects more than 1 in 100 people. Over 7 in 100 people are likely sensitive to gluten.
Glutens and other storage proteins are found in the endosperm, which is the inside of all seed foods. They are not in the bran-rich outer coating, which is why refined grains may not be as healthy as whole grains. All seeds contain storage proteins, but only the wheat family contains glutens. So, what’s so special about gluten?.
Glutens have long chains of amino acids that are repeated over and over again (they are high in proline and glutamine) that are hard for our enzymes to break down. [Remember that the mother plant only wants the baby plant to digest this protein. “Prolamins” are proteins that have a lot of proline in them. They are thought to be especially bad for our immune systems. All grains have prolamins, but the types found in wheat (gliadin), rye (secalin), and barley (horedin) seem to be especially bad for people whose immune systems are weak. [A small number of people are also sensitive to avenin, the prolamin found in oats. ].
The problem with gluten not being easily digested is not just that it’s hard to get healthy proteins from foods that are high in gluten. The issue is that “toxic gliadin peptides,” which are partially digested glutens, can mess up the digestive and immune systems of people who are genetically more likely to get Celiac disease and gluten sensitivity.
For those who really are allergic to wheat, the protein omega-5 gliadin in wheat is what makes them sick. This protein is only found in wheat—not in barley, rye, or triticale.
Anything that stops the body from digesting, absorbing, or using a nutrient is called an antinutrient. Antinutrients in seed foods include enzyme inhibitors and phytic acid.
There are chemicals in seed foods that fight our digestive enzymes and make it harder for us to break down food. These include protease inhibitors, which block protein digestion, and amylase inhibitors, which block starch digestion. Amylase inhibitors do not survive digestion, so they are not a concern. Plus, cooking mostly gets rid of protease inhibitors, so they wouldn’t be a problem in well-cooked seed foods either.
Phytic acid, however, cannot be destroyed by cooking. This acid is called phytic acid, which comes from plants because it is not found in animal foods. It’s mostly found in the bran-rich outer layer of seeds, which is one reason why whole grains aren’t always healthy.
Phytic acid is a mineral magnet. It binds to certain minerals in the foods we eat, and removes them from our bodies. This can lead to mineral deficiencies, such as iron-deficiency anemia. The “non-heme” form of iron in plant foods is harder to absorb than the “heme” form found in animal foods. ].
Below are results from two human studies of phytic acid. In the first study [Brune 2019], researchers found that bran stops the absorption of about 90% of the iron in wheat rolls. This was true for both meat eaters and long-time vegetarians. This shows that the body does not get used to the antinutrient effects of phytic acid, even in people who have been eating a lot of plants for years.
The second graph [Solomons 1979] shows the degree of interference that phytic acid can have on zinc absorption. Oysters are rich sources of zinc. If you eat oysters by themselves, the zinc level in your blood will rise nicely, which means they are being absorbed well. People only took in about half of the zinc from oysters when they were eaten with black beans. When oysters were eaten with corn tortillas, they took in almost none of the zinc from the oysters. This is not a subtle effect. This study is important because it shows that phytic acid doesn’t just stop the body from absorbing nutrients from seeds; it also stops the body from absorbing nutrients from other foods that are eaten with seeds.
*Note that taking vitamin C or eating vitamin C-rich foods along with high-phytate foods can improve mineral absorption.
It binds best to “positively charged, multivalent cations,” which means it likes minerals with more than one positive charge, like iron (Fe 2), calcium (Ca 2), zinc (Zn 2), magnesium (Mg 2), and copper (Cu 2). These are all minerals our bodies need and must get from food. Sodium (Na 1) and potassium (K 1), which only have one positive charge, don’t stick to it well. ].
Phytic acid can also bind to food proteins and to our digestive enzymes, interfering with protein absorption.
Are grains (and other seeds) good for us?
When farming began around 5,000 to 10,000 years ago, grains and beans became an important part of people’s diet for the first time. People used to hunt and gather food, and depending on where they lived and the time of year, they ate different kinds of fruits and vegetables. That’s not very long in terms of evolution, so most of us haven’t had time to get used to these tough foods. According to historical and anthropological records, people’s health around the world got worse after agriculture began. Most people were shorter, and their bodies showed signs of mineral deficiencies, malnutrition, and infectious diseases. Around the same time that grains and legumes were introduced to humans, dairy products were also eaten. This makes it hard to say whether health got worse because of seed foods, dairy products, or both. As you’ll see below, though, it’s easy to see how the health problems that started happening after farming could have been caused by ingredients in seed foods, while it would be harder to connect them to ingredients in dairy foods (see my dairy page).
Are Beans Bad for You? Health, Longevity, & Inflammation Effects of Legumes (+ Lectins & Phytates)
FAQ
Is bean considered a grain?
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What seeds are not grains?