As a gastroenterologist, I focus a lot on my patients’ digestive systems (aka their gut). The gut is as valuable to the body as the brain, the heart, and any other vital organ or system. The state of the gut can affect one’s health and well-being dramatically, and yet it’s surprising how some people never really pay attention to it.
Your gut is often referred to by professionals as your “second brain”. This is because it has such an intimate connection with your actual brain and carries much of the responsibility for how you feel mentally and emotionally on a day-to-day basis. Have you ever talked about having that “gut feeling” when you’re making a decision? Or been told to trust your “gut instinct”? As we progress in the study of physiology, we come to understand more and more that the brain-gut connection is far from metaphorical.
There is a network of nerves called the enteric nervous system which contains millions of neurons that connect the gastrointestinal system (gut) with the brain. This system is so expansive that it can operate independently of the central nervous system (hence the nickname “second brain) although the two do communicate regularly.
In this article, I want to discuss the importance of maintaining good gut health as well as share my top tips for improving the health of your digestive system.
Why Is Gut Health Important?
Your gut is home to trillions of bacteria, collectively known as your microbiome. Your microbiome, on its own, weighs as much as 2-3 pounds. While certain bacteria create infection and disease, the majority of bacteria in your microbiome actually support your immune system and overall health. Throughout your body, you have at least as many bacteria as you do cells (possibly more!). (1)
There are over 1000 species of bacteria in the average human microbiome. Each one is different and plays various roles in helping you to maintain optimum health. Here are just a few of the main things your microbiome influences:
- Metabolism. Studies have found that the microbiome plays a role in metabolism and an unhealthy one may influence the risk of developing metabolic syndrome, obesity, and diabetes.
- Digestion. The bacteria in the microbiome help the body to digest all manner of food. (7) Gut bacteria are particularly important for digesting fiber. (8)
- Immune System. A healthy microbiome plays a huge role in strengthening the immune system and preventing the development of disease. (6)
- Heart health. Studies have found that gut bacteria may increase or decrease your risk for heart disease. When you eat certain foods like red meat or eggs, certain bacteria make a chemical that turns into TMAO. This may influence the buildup of cholesterol in the blood vessels. (2)
- 5 Senses. Studies have found that the balance of bacteria in your microbiome affects how you process things like light, sound, sights, flavors, and textures. (4)
- Emotional/Mental Health. A large percentage of your body’s “happy hormones” like serotonin is produced in the gut. Studies have found that brain levels of serotonin are regulated by the gut microbiome, especially during early life. This means that if you had poor gut health during important developmental stages as a child, it may increase your risk for anxiety and depression as an adult. (5)
- Weight/Obesity. An unhealthy microbiome may increase one’s risk for obesity. Studies have found that gut bacteria balance affects brain signaling for feeling hungry or full, as well as overall appetite. (6)
Where is the gut located in the human body?
The gut is another term for the body’s gastrointestinal system, which actually starts in the mouth and travels all the way to the anus. Basically, the pathway that takes food from the entrance to the exits is considered part of the gut. The largest portion of the gut is in the abdominal region which holds your stomach and small and large intestines.10 Best Ways To Support Gut Health
Now that we’ve discussed what the gut is and why it is important, let’s dive into how you can care for your gut so that it will support you throughout your life.
#1 Increase Intake Of Prebiotics
Prebiotics are foods that feed the bacteria in your gut, thus promoting the growth of beneficial microbes. These foods are actually not digestible by human cells and we need them for the purpose of fueling our microbiome.
Prebiotics are generally fiber or complex carbs. They can be found in many fruits, vegetables, and whole grains.
Certain prebiotics has also been found to help reduce insulin, triglycerides, and cholesterol levels in people who are overweight and obese. (9, 10, 11, 12, 13)
#2 Increase Intake Of Probiotics
Probiotics are specific strains of bacteria that help to populate the gut and keep it in a positive balance. Although they don’t normally permanently colonize your intestines, they do help to change the composition of your microbiome and may have a positive impact on metabolism and overall well-being. (14)
Taking probiotics is not always necessary nor impactful if your gut is already in great condition, but has been found effective in helping those whose gut microbiome has been compromised. This may happen, for example, due to a round of antibiotics, poor long-term dietary decisions, illness, autoimmune disorders, smoking, and/or exposure to certain chemicals in the environment. (15)
In other words, taking a high-quality probiotics supplement may be very useful in restoring the gut microbiome of someone who is or has been sick. But they may not be needed nor particularly beneficial in those who are already healthy and thriving.
#3 Include Fermented Foods
Eating naturally fermented foods has been found to strengthen the immune system, help treat candida, regulate sugar and carb cravings, form a protective lining in the intestines that shields against pathogens, and may even help to reduce anxiety. (16, 17, 18)
Most cultures around the world include fermented vegetables or products in their daily diet. Here are a few of the best kinds to start adding to your grocery list (or making at home).
- Kefir
- Kombucha
- Sauerkraut
- Pickles
- Miso
- Tempeh
- Natto
- Kimchi
- Raw, unpasteurized cheese
- Yogurt (choose one with low sugar content)
#4 Eat More Fruits, Vegetables & Leafy Greens
Whole fruits, vegetables, and leafy greens contain prebiotics and are also full of important vitamins, minerals, and micronutrients. There are a lot of different things your body needs to get from food in order to thrive, and one of the best ways to ensure you’re getting them is by eating a wide variety of plant-based foods. These naturally contain what you need, and in the most bio-available form (unlike expensive supplements which often end up in your urine instead of your cells).
Studies have found that a diet high in fruits and vegetables may prevent the growth of some disease-causing bacteria. (19) Fruits and veggies also help to increase healthy bacteria in the gut, strengthening the microbiome and in turn the immune system. (20, 21, 22, 23)
#5 Diversify Your Diet
Your microbiome is filled with hundreds of species of bacteria, each of which has certain roles and provides specific benefits to your health. Each species thrive off of different nutrients. When you eat a diverse diet, you support a diverse microbiota which is considered to be healthier and stronger than one lacking in diversity. (24, 25, 26, 27, 28)
How to diversify your diet? Try a new fruit or vegetable each time you go shopping. Make recipes from different countries that call for ingredients you wouldn’t normally use. Try to focus on what foods are in season. Eat food that is grown locally.
It can be a fun family challenge to see who eats the most variety of fruits, veggies, nuts, or seeds during a week.
#6 Eat Whole Grains
Research has found that eating whole grains helps to promote the growth of various beneficial bacterial strains in the large intestine. They also increase feelings of fullness, reduce inflammation, and may reduce the risk of heart disease. Whole grains consist largely of fiber and non-digestible carbs that feed the microbiota in your intestine. (29, 30, 231, 32, 33, 34)
Here are 10 whole grains to focus on in your diet:
- Quinoa
- Brown Rice
- Oats
- Barley
- Buckwheat
- Whole wheat
- Rye
- Bulger
- Couscous
- Organic corn
#7 Follow An 80/20 Diet
If you are in overall good health, I recommend following an 80/20 diet lifestyle. 80% of the time you should be focused on healthy, real, unboxed/unprocessed foods. The rest of the time you can have a little treat or something not as healthy. This ensures you are getting good nutrition to keep your body in optimum health while also enjoying yourself once in a while and indulging in your favorite treats.
#8 Live A Movement-Oriented Lifestyle
What does exercise have to do with your microbiome? Quite a lot, surprisingly! Studies have found that regular exercise increases species diversity in your microbiome AND reverses gut imbalances related to obesity. (34, 35)
Scientists in Ireland found that professional athletes have far more diverse microbiomes than their less-active peers. (36)
It’s never too late to begin an active lifestyle. However, it has been shown that an active lifestyle in one’s early years has a significant impact on how healthy and diverse your microbiome is as you get older. (37)
#9 Use Natural Household Cleaners
Chemical, antibacterial household cleaners may leave your home surfaces clear of bacteria, but this is actually not what is best for your health. These chemicals not only kill harmful bacteria but beneficial bacteria, too. Exposure to naturally occurring bacteria is actually vital to building a strong microbiome and immune system.
Studies have found that parents who suck their baby’s pacifiers to clean them, for example, benefited their child’s gut bacteria more than the parents who boiled the pacifiers in water. These kids receive important immune stimulation from the microbes in their parent’s saliva. (38)
Children who grow up around pets are less likely to develop allergies because of exposure to certain pet-related bacteria strains like L. Johnsonii, which is an essential strain for a healthy gastrointestinal tract.Β (39)
Opt for natural household cleaners made from ingredients like baking soda, vinegar, lemon juice, castile soap, etc.
Another motivation for ditching conventional household chemicals: recent research has found that inhaling them consistently over the years can be as damaging to your health as smoking! (40)
#10 Get Outside & Get Dirty
There are tremendous benefits to spending time outdoors in the dirt for your microbiome! Being in contact with the earth exposes your immune system to trillions of microorganisms that exist in the ground and in plants. Studies have found that exposure to soil bacteria can improve quality of life by increasing feelings of happiness, and vitality and improving cognitive function. (41, 45)
One study found that certain kinds of soil bacteria help to activate groups of neurons in the brain responsible for producing serotonin, aka the “happy hormone”.(42)
Researchers have confirmed that exposure to outdoor microbes in childhood is linked to a more robust immune system and is linked to lower rates of asthma and allergies. (43, 44)
Frequently Asked Questions About Gut Health
Q. Can gut health cause anxiety?
A. The gut and brain are intimately connected. Trouble in the gut may trigger anxiety and stress; these feelings are symptoms that something is amiss in the body. Another reason the gut is linked to anxiety is that certain hormones that create feelings of calm and happiness (like serotonin) are created and secreted by the gastrointestinal system. If something in the gut is amiss, adequate amounts of these hormones may not be produced.
Q. Can gut health cause/affect acne?
A. If your body is unable to filter out toxins adequately during digestion (due to poor gut health or toxin overload), the lymphatic system will try to eliminate them through the skin. This can lead to breakouts, acne, rashes, eczema, and other skin problems.
Q. Can gut health cause depression?
A. Poor gut health has been linked to increased risk for depression, anxiety, schizophrenia, and even autism. (46)
Q. How does gut health affect mood?
A. Microbes in the gut help to produce hormones such as serotonin; a “happy hormone” that helps one to feel happy and calm. Poor gut health can affect the body’s ability to produce or use adequate amounts of this hormone and others likewise responsible for mood.
Q. What is poor gut health?
A. Poor gut health refers to a gastrointestinal system that is damaged, has poor amounts of beneficial bacteria, or is otherwise unable to perform optimally.
Q. Are pickles good for gut health?
A. Pickles made from brine (salt water) contain generous amounts of beneficial bacteria that promote good gut health.
Q. Where do gut bacteria come from?
A. Infants receive bacteria from their mother through the birth process and throughout life are exposed to bacteria from food, animals, plants, dirt, other people, etc.
Q. Which gut bacteria cause weight loss?
A. One study found that a higher ratio of Prevotella-to-Bacteroides bacteria was linked to more weight loss. (47)
Q. Can gut flora be restored?
A. Yes. After an event that destroys the gut flora (a round of antibiotics, for example) one can restore their gut flora through high-quality probiotic supplementation, incorporating prebiotics and fermented foods into the diet, temporarily removing any foods that damage gut bacteria (sugar, trans fats, artificial sweeteners, etc), using healing supplements such as collagen, fish oil, and zinc (among others), and eating a healing diet. Work with a medical professional to determine the best plan for you and your unique situation.
Q. When does gut bacteria change brain function?
A. Your microbiome plays a significant role in your mental health. Studies have found the gut impacts how we respond to stress. Research has also found that the health of our gut can increase or decrease our risk for anxiety and depression. There is no question that the brain and gut are intimately linked. (48,49)
Conclusion
Hippocrates is often quoted as saying that “All disease begins in the gut.” It may also be concluded that good health begins in the gut. If you are looking to improve your health and vitality, heal from disease, gain more energy, improve your moods, or simply find a better quality of life, your gut is the first place to begin. I pay close attention to the gastrointestinal health of all of my patients. You simply cannot thrive if there are problems happening in your core.
Did you find this information useful? What other questions do you have about the gut?
Have more questions? Ask Dr. Partha Nandi MD Here!
References
- https://www.nature.com/news/scientists-bust-myth-that-our-bodies-have-more-bacteria-than-human-cells-1.19136
- https://www.nih.gov/news-events/nih-research-matters/red-meat-heart-disease-link-involves-gut-microbes
- https://www.nature.com/articles/s41598-017-01387-y
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5530613/
- https://www.sciencedaily.com/releases/2012/06/120612115812.htm
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4759265/
- https://www.anl.gov/articles/exploring-role-gut-bacteria-digestion
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3705355/
- https://www.ncbi.nlm.nih.gov/pubmed/23135760
- https://www.ncbi.nlm.nih.gov/pubmed/23303873
- https://www.ncbi.nlm.nih.gov/pubmed/22555633
- https://www.ncbi.nlm.nih.gov/pubmed/21059476
- https://www.ncbi.nlm.nih.gov/pubmed/7698613
- https://www.ncbi.nlm.nih.gov/pubmed/21992949
- https://www.ncbi.nlm.nih.gov/pubmed/25157183
- http://www.ncbi.nlm.nih.gov/pubmed/16696665
- https://draxe.com/fermented-foods-reduce-social-anxiety/
- https://draxe.com/treating-candida-with-fermented-vegetables/
- https://www.ncbi.nlm.nih.gov/pubmed/26757793
- https://www.ncbi.nlm.nih.gov/pubmed/20304079
- https://www.ncbi.nlm.nih.gov/pubmed/20187995
- https://www.ncbi.nlm.nih.gov/pubmed/22060186
- https://www.ncbi.nlm.nih.gov/pubmed/24642201
- https://www.ncbi.nlm.nih.gov/pubmed/22797518
- https://www.ncbi.nlm.nih.gov/pubmed/22972295
- https://www.ncbi.nlm.nih.gov/pubmed/22699609
- https://www.ncbi.nlm.nih.gov/pubmed/21885731
- https://www.ncbi.nlm.nih.gov/pubmed/27110483
- https://www.ncbi.nlm.nih.gov/pubmed/17761020
- https://www.ncbi.nlm.nih.gov/pubmed/23038174
- https://www.ncbi.nlm.nih.gov/pubmed/26904005
- https://www.ncbi.nlm.nih.gov/pubmed/20487589
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939539/
- http://www.ncbi.nlm.nih.gov/pubmed/25021423
- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4082611/
- http://gut.bmj.com/content/early/2014/04/29/gutjnl-2013-306541
- http://www.colorado.edu/news/releases/2015/12/29/early-life-exercise-alters-gut-microbes-promotes-healthy-brain-and-metabolism
- http://pediatrics.aappublications.org/content/early/2013/04/30/peds.2012-3345
- http://www.pnas.org/content/111/2/805.abstract
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5089137/
- https://www.ncbi.nlm.nih.gov/pubmed/15151947
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1868963/
- http://www.nature.com/news/early-exposure-to-germs-has-lasting-benefits-1.10294
- https://www.ncbi.nlm.nih.gov/pubmed/11597666
- https://www.newscientist.com/article/dn18967-eat-bacteria-to-boost-brain-power/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4662178/
- https://www.medicalnewstoday.com/articles/319411.php
- http://www.tandfonline.com/doi/full/10.1080/19490976.2017.1353849
- https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-017-0321-3
