It’s no secret that whole grains are an important part of any healthy diet. Many studies have shown they can reduce your risk of heart disease, type 2 diabetes, and even certain cancers. But recent research indicates they also have surprising benefits for your gut and immune system.
Keep reading to learn the benefits of whole grains for gut health and boosting your resistance to infection. But first, what constitutes a whole grain, and why are they better than refined varieties?
Whole grains vs refined grains
Whole grains offer a significant nutritional advantage over refined grains. As part of the essential grain food group, some of the most well-known options include:
- Whole wheat
- Brown rice
Unlike refined grains, whole grains retain the bran, germ, and endosperm of the seed, providing a wealth of vitamins, minerals, and antioxidants. Their fiber content supports digestive health, helps control blood sugar levels, and promotes a feeling of fullness.
Refined grains undergo processing that breaks them down into a finer texture, primarily to extend shelf life. Unfortunately, this milling process removes dietary fiber, iron, and various forms of B vitamins from the starch. Although iron and B-vitamins can be added back through enrichment, the fiber content generally remains depleted.
Common examples of refined grains include:
- White flour
- White bread
- White rice
- Corn grits
By opting for whole grains, you prioritize nutrition and enjoy more wholesome benefits.
Let’s take a look at how whole grains impact your gut–specifically the microbiota living in it, and how that affects your immune system.
Understanding gut microbiota and the immune system
Your gut microbiome, the diverse community of bacteria and organisms in your digestive tract, plays a crucial role in overall health, including immune and inflammatory functions.
With about 80% of the body’s immune system located in the gut, specialized immune cells throughout the digestive tract interact with the organisms, influencing immune responses.
Taking good care of your gut supports your immune system and contributes to your overall well-being.
How do whole grains increase gut health?
Recent research shows that eating whole grains contributes to greater gut microbiota diversity and abundance.
Being rich in dietary fiber, whole grains provide nourishment for beneficial bacteria in the gut, such as Lachnospira. Lachnospira produces short-chain fatty acids, which serve as an energy source for colon cells, regulate intestinal barrier function, and provide anti-inflammatory, immunoregulatory, anticancer, and anti-obesity benefits.
New research on whole grains, gut health, and immunity
In a recent eight-week study with 81 participants, researchers compared the effects of a diet rich in whole grains versus refined grains on immune and inflammatory responses, gut microbiota, and stool frequency in healthy adults.
During the first two weeks, all participants consumed a weight-maintaining Western-style diet high in refined grains. Afterward, 40 participants continued this diet while 41 participants switched to a whole-grain-rich diet.
The whole-grain group showed an increase in beneficial bacteria like Lachnospira and a decrease in inflammatory bacteria like Enterbacteriaceae, possibly due to a more favorable stool pH that occurs from consuming a diet rich in whole grains. Consuming whole grains was also associated with higher levels of memory T cells, which play a crucial role in strengthening the body’s immune defenses.
In contrast, consuming refined grains was linked to a reduction in TNF-alpha production, a proinflammatory but beneficial compound that helps protect localized areas of the body from invasion or injury when immune cells are stimulated.
The changes in memory T cells and TNF-alpha were modest, and further studies are needed. But these findings still provide valuable insights into the potential benefits of eating whole grains.
How much whole grain should you eat for gut health?
According to the 2015-2020 Dietary Guidelines for Americans, women should consume at least three ounces of whole grains per day, while men should aim for four ounces. That’s approximately one to two cups of grains like brown rice or oatmeal daily.
By incorporating healthy, whole grains into your diet, you’ll be able to unlock the many nutritional benefits they have to offer for your gut, immune system, and overall well-being.
What are the best whole grains for gut health and immunity?
Here are some of the best whole grains to support your wellness journey:
- Whole oats
- Brown rice
- Whole wheat
- Whole-grain rye
- Bulgur wheat (also known as cracked wheat)
- Whole barley
- Corn (opt for organic varieties to avoid GMOs)
- Amaranth (an ancient grain similar to quinoa)
If you’re sensitive to gluten, you’ll want to avoid grains like whole wheat, rye, bulgur, and barley. Instead, stick with gluten-free options like oats, buckwheat, millet, quinoa, brown rice, corn, and amaranth.
Whole grains are an integral part of a well-rounded and nourishing diet, with benefits that extend far beyond their role in mitigating chronic diseases. By incorporating these nutrient-rich foods into your daily life, you can improve the diversity of your gut microbiota and foster a robust immune response, ultimately enhancing your overall well-being and longevity.