Human health starts in the gut. All of these bacteria in the microbiome play an important role in the maintenance and development of the human body. They help digest our food, regulate our immune system, protect against other bacteria that cause disease, and produce vitamins including your B vitamins related to energy and vitamin K, which is needed for blood coagulation. Gut microbes balance our metabolism, our hormones and help regulate our nervous system. The human gut is the workhorse  of human health. 

In the gut microbiota, the “good” bacteria do more than just help with digestion. They help keep your “bad” bacteria in check and they are key in reducing inflammation and preventing disease. Diversity of species plays a critical role in this. When you have a healthy balance of bacteria in your gut, it's called equilibrium. When things are working the way they are supposed to, we have a diverse, abundant community of microbes living in harmony in our colon. 

With about 60 to 70 million Americans dealing with digestive issues, the more we can understand about how to benefit our gut is absolutely relevant to our discussion around making positive changes in our wellbeing.

1. Improve Your Gut Health By Making Sure You Are In A Good Place Mentally

Researchers have found that a lesser known nervous system in our gut (also known as our second brain) communicates with the primary brain in our head. Researchers have found that our gut has as many nerve cells as the spinal cord. Together, they communicate often and play a key role in certain diseases in our bodies and overall health. For example, gut bacteria manufacture about 90 to 95 percent of the body's supply of serotonin, which influences both mood and gastrointestinal (GI) activity.

The gut-brain connection is no joke; it can link anxiety to stomach problems and vice versa. Have you ever been nervous about something and then had a sense of urgency to use the bathroom? When you get excited have you ever felt butterflies in your stomach?  We use these expressions because the gastrointestinal tract is sensitive to emotion. Anger, anxiety, sadness, elation — some of many feelings we experience that can trigger symptoms in the gut.

This gut-brain connection goes both ways. A troubled gut can send signals to the brain, just as a troubled brain can send signals to the gut. Chronic anger, sorrow or fear can have long-term effects on our overall well being. For some GI disorders, it is difficult to try to heal a distressed gut without considering the role of stress and emotion. Here are some specific areas to focus on to make sure you are in a good place mentally:

Sleep

Your quality of sleep and gut microbiome are interconnected. Poor sleep can negatively affect your gut microbiome, which can, in turn, lead to additional health issues. After dieting, sleep is the next important aspect of gut health. Sleep offers a lot of repair to our brain so it makes sense that sleeping can offer benefits to our second grain, the gut. It can give our gut a chance to reset and prepare for the next day’s work of digesting more food. 

 *learn more about sleep and its impact on our brain here

Trauma

Trauma can prevent you from having proper gut functioning. You can do everything right, but if you have unresolved conflict from a prior or current traumatic event, you will not repair your gut until you begin working towards healing from the impact trauma has wreaked on your body. Remember, you can’t heal if your past trauma is being ignored.

Anxiety

60 percent of Irritable Bowel Syndrome (IBS) patients have one or more psychiatric disorders. The most common mental ailment people with irritable bowel syndrome have is anxiety. Keeping your stress under control can help you prevent or ease IBS Symptoms. Many doctors are now teaching their patients about relaxation techniques such as deep breathing or visualization to help manage IBS symptoms. 

2. Improve Your Gut Health By Eating More Fiber

Fiber is the true heart and soul of gut health. Fibers are carbohydrates which can’t be digested by humans without the help of their gut bacteria. There is indisputable evidence that fiber is always 100 percent beneficial for your cardiovascular system to your brain and even your hormonal health. One thing to remember is that all plants contain fiber, and exclusively plants contain fiber. Not only that, but each plant contains a unique type of fiber. Fiber in general is the preferred food of your gut microbiome. 

Microbes are picky eaters. They are all unique and have their specific dietary preferences. When you eat a specific plant, the unique fiber in that plant feeds a unique group of microbes. Scientists are calling this a guild. There is a guild that forms to unpack the specific fiber in your diet and they reward you by producing short-chain fatty acids. 

The type of fibers you consume are typically divided into two categories: soluble or insoluble fibers. Soluble fibers are like sponges that bind to cholesterol and carry them out of your body. Soluble fibers are typically found in fructans like inulin, beta-glucans, pectins (whole grains, potatoes, legumes, vegetables and fruit). Most soluble fibers are highly fermentable, making it great to increase your beneficial bacteria Bifidobacterium and Lactobacillus. 

Insoluble fibers help sweep out our more harmful gut bacteria and keep your digestive system moving along and minimize blockages. Insoluble fibers are known as cellulose, hemicellulose and lignins found in bran, cereals, legumes, vegetables and in the skins of fruit.

The reality is that almost all Americans (97 percent to be exact) don’t consume enough fiber. Most Americans are missing out on some amazing by-products by not feeding their gut bacteria more fiber. High-fiber foods, such as fruits, vegetables, legumes and whole grains, encourage the production of short-chain fatty acids, which play an important role for overall health and in preventing and fighting disease. They can help reduce the risk of certain inflammatory diseases including heart disease, obesity, type 2 diabetes, metabolic syndrome to name a few.

About 95 percent of the short-chain fatty acids (SCFAs) that are produced when fiber is fermented in the colon and the primary ones are:

• Acetate 
• Propionate
• Butyrate 

All three have significant anti-inflammatory properties and they work together for the good of your health. Butyrate is known specifically to help heal and fix the lining of the gut and increase colonic motility (if you suffer from IBS then you want this). Butyrate is also known for altering gene expression to help inhibit cancer formation. Propionate is an important substrate for the liver to make energy (glucose) and recent studies found that athletic individuals have gut bacteria that produce propionate in larger amounts than more sedentary individuals.

 All types of SCFAs have been shown to protect against congestive heart failure and high blood pressure, and protect the brain from Parkinson’s disease. SCFAs may even help with attention deficit hyperactive disorder (ADHD). Children on a high-fiber diet may demonstrate better cognitive control than children who eat a lower fiber diet. 

Each type of fiber we consume produces a different mix of these SCFA’s. So it is important to consume a diversity of plants to get the benefits of all three different kinds of SCFA. Some of the general benefits to having your bacteria produce more SFCAs include: 

• Appetite regulation
• Reduces stomach pH level to inhibit pathogen growth
• Keeps our energy levels consistent
• Helps multiple organs like our liver function properly

General recommendations by the American Dietary Guidelines are 25 g of fiber daily for females and 38 g for males. Current average American intake is about 15 g daily. Focusing on eating more plants is a goal that would benefit many of us for so many reasons and exceeding these recommendations would provide multiple benefits for our health. We gush more about reasons why we love fiber over on this blogpost.

3. Improve Your Gut Health By Eating At Least 30 Different Plants Weekly

The food industry has structured our diet to be based around soy, corn, and wheat.

However, diversity of plants is key to our health. Biodiversity is a measure of health within any ecosystem. Your gut microbiota is just as much of an ecosystem as the Amazon rainforest. It thrives on balance and harmony. In the rainforest, all animals, plants, and bugs exist with a purpose. They are all key to harmonious balance in the Amazon. The loss of even just one of those species would have unintended consequences and diminish the health of the entire ecosystem. This is why biodiversity is critically important to any ecosystem. Thanks to research we know that the human gut is no exception. There are trillions of bacteria and it is critically important to have balance by an abundant and diverse community of microbes living in harmony with each other. 

Diversity of microbes is a measure of gut health, and you only get a diversity of microbes when you eat a diversity of plants. When you eat a broad diversity of plants you are consuming an array of different fibers, resistant starches, polyphenols etc that will feed the many different types of microbes in your gut. The end result is a strong, resilient gut. The golden rule for gut health is diversity of plants.

What does a healthy gut diet look like?

Gut microbiota diversity is a key regulator of human health. Studies show that high fat, low fiber diets decimate gut microbiota diversity. And low fat, high fiber diets produce healthy gut diversity. 

There are specific plants that have more beneficial properties for gut health than others. Not all of these plants will be consumed in equal measure, but they are foods that you want to get in your body on a daily basis if possible. 

FERMENTED FOODS (sauerkraut, kimchi, miso, tempeh, etc)

FRUITS (bananas, berries, citrus fruit, etc)

GREENS (spinach, kale, romaine, swiss chard, arugula, etc)

WHOLE GRAINS (brown rice, quinoa, oatmeal, whole wheat, etc)

OMEGA-3 SEEDS (chia, hemp, and flax seeds)

AROMATICS (onions, garlic, shallot)

LEGUMES (Black beans, navy beans, pinto beans, lentils, chickpeas, etc)

MUSHROOMS (white button, portobello, shiitake, oyster, etc)

SEA VEGETABLES (seaweed: kelp, nori, wakame, etc)

CRUCIFEROUS VEGETABLES (which are the ultimate cancer crushers--broccoli, cabbage, brussel sprouts, cauliflower, bok choy etc)

SPICES especially cumin and cloves are high in polyphenols

Polyphenols

The majority of the polyphenols we eat end up in our large intestine and potentially have some antioxidant effects on our gut tissues, which is really good when it comes to making sure our second brain is protected and in optimal shape. In addition, polyphenols are a great prebiotic for our gut bacteria because they can activate the polyphenols. When they activate them, it unlocks some amazing abilities like killing off harmful bacteria. What’s even neater is the more you alter your gut bacteria with a high-fiber diet rich with plant varieties, your bacteria get even better at unlocking and activating polyphenols in your diet. The highest polyphenol-containing foods are spices like cumin and cloves. Berries, cocoa, dark chocolate, coffee and tea, hazelnuts and almonds, spinach, broccoli, soyfoods, whole wheat and rye bread, white and black beans are also polyphenol-containing foods to incorporate in your varied high-fiber diet. 

Sulforaphane 

Sulforaphane is a powerful phytochemical and can be found in cruciferous vegetables like broccoli, kale, cabbage, and watercress. Sulforaphane has been shown to reduce the ability of cancerous cells to multiply and slow tumor growth or reduce its ability to spread to other parts of the body. It also blocks mutations in DNA that lead to cancer. Sulforaphane neutralizes toxins and calms inflammation. In one study, sulforaphane corrected gut dysbiosis by increasing healthy gut microbes, increasing butyrate release, and repairing the intestinal lining to reverse leaky gut by upregulating tight junction formation. 

Raw vegetables have the highest levels of sulforaphane. One study found that raw broccoli had ten times more sulforaphane than cooked broccoli. But by far, the food with the highest amount of sulforaphane is broccoli sprouts. 

What’s Good For Your Gut, Is Good For You Too

The human gut is more complex than previously thought and has a huge impact on whole body health. A healthy gut contains healthy bacteria and immune cells that ward off infectious disease and can help prevent chronic diseases. Key to this is eating fiber-rich foods so that our gut produces short-chain fatty acids that ward off disease. A healthy gut also communicates with the brain through nerves and hormones, which helps maintain general health and well-being. The key to a healthy gut, body and mind is eating a diversity of plants. Make it your goal to eat at least 30 different whole plant foods every week to give your gut a fighting chance. 

Suggested Reading:

Good For Your Gut: A Plant-Based Digestive Health Guide And Nourishing Recipes For Living Well by Desiree Nielsen, RD

Fiber Fueled by Will Bulsiewicz, MD, MSCI

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