Gut Health 101: What You Need to Know About Your Gut

11.19.2025 | Category: Eating Well

Expertly reviewed by: Dr. Manoj Pawar, MD, FAAP
Chief Medical Officer, Mutual of Omaha

Estimated Read Time: ~9 minutes

Summary: A healthy gut is key to overall physical and mental well-being. Here’s what you need to know about its impact on your body and how to maintain it.

Your gut, also known as the gastrointestinal (GI) tract, is made up of the esophagus, stomach and intestines. It processes and breaks down the food so that your body can use it for energy, growth and healing.

Apart from its critical role in digestion, gut health is closely linked to your immune system, blood sugar levels, cardiovascular health and even your mental health. Let’s demystify gut health and explore how a healthy gut could positively impact your well-being.

What is “gut health”? Understanding the basics

Your gut plays a role in keeping you alive and kicking, but it doesn’t work alone. Trillions of microorganisms, including bacteria, viruses, fungi and other microbes, live in the gut and play a key role in keeping you healthy. This ecosystem of microorganisms is called the ‘gut microbiome’ and is, by far, the busiest microbiome of the body.

One of the most fascinating aspects of the gut microbiome is its diversity. A diverse range of microbes in your gut helps your body better manage infections and inflammation, which in turn impacts your overall physical health and energy levels.

A wide variety of microbes support your body’s ability to recover after exercise or physical strain. Some strains help produce vitamins, anti-inflammatory compounds and metabolic regulators that give your body extra tools to stay balanced and energetic.

A healthy gut and a healthy gut microbiome help ensure good digestion, blood sugar regulation and strong immune function¹, provided you aren’t suffering from other gut issues. It can even boost your mental health.

Why a healthy gut is crucial for digestion, immunity and mental health

The gut and brain are connected through the gut-brain axis, a network of nerves and biochemical signals that enable two-way communication. Central to this connection is the vagus nerve. It can trigger the fight-or-flight response, an indicator of heightened stress, if it misfires due to certain foods or emotional reactions.

Stress can harm your gut lining because the vagus nerve, which runs from the brain to the intestine, is involved in this process. Effective stress management techniques, such as deep breathing or mindfulness, can help protect your gut by reducing the impact of stress on the vagus nerve.

Nearly 90% of serotonin, aka the “happy hormone,” is produced in the gut and tied to the vagus nerve². To maintain mental well-being and peak performance, it’s vital to nourish your gut and replenish its beneficial bacteria.

Even short-term gut disturbances can impact your mood or focus. You may notice that after a heavy, processed meal or a stressful day, your energy levels dip or your mind feels foggy. These are subtle signs that your gut and brain are talking to each other.

The gut microbiome also supports your immune system. Approximately 70% of your body’s immune cells are located in the gut, in an interdependent relationship³. The immune system influences the diversity of the gut, and the microbiome strengthens immune function. A healthy gut or a diverse and rich microbiome has a direct effect on inflammation and, therefore, on your immune system.

According to a research study, gut bacteria also aid the recovery of patients with compromised immunity.⁴ Studies indicate correlations between gut microbiome diversity and focus, alertness and resilience under stress⁵.

Recognizing signs of an unhealthy gut

Some common signs and symptoms of gut imbalances may include:

Digestive issues such as bloating, gas, constipation, diarrhea or Irritable Bowel Syndrome (IBS)
Persistent fatigue and low energy levels
Unexplained weight changes
Food intolerances or sensitivities
Skin problems such as acne or eczema
Mood disturbances, including anxiety, depression or irritability
Auto-immune problems such as rheumatoid arthritis or Type 1 diabetes

If you often feel bloated after meals, crave sugary foods or have mood swings that seem tied to what you eat, your gut microbiome might be out of balance. If you experience any of these symptoms regularly, it’s important to consult a healthcare professional to identify underlying issues and create a personalized plan to improve your gut health.

Common causes of poor gut health

Several factors can contribute to an unhealthy gut:

A diet high in processed foods, sugar and unhealthy fat depletes beneficial gut flora and may cause inflammation and disease.
Exposure to pollutants, pesticides, pathogens, and toxins can reduce microbiome diversity.
Illness and antibiotic use can allow harmful bacteria to outnumber beneficial microbes.
Sedentary habits, chronic stress and inadequate sleep can disrupt eating habits, disturb the internal body clock and the microbiome’s sensitive balance.

People in industrialized societies tend to have a less diverse and more vulnerable microbiome. This is connected to the widespread use of pesticides on produce, antibiotics and hormones in animal farming and airborne pollution. Interestingly, modern hunter-gatherers in Africa with non-industrial lifestyles continue to have thriving microbiomes⁶.

How to improve your gut health — diet and lifestyle tips

Improving gut health is a gradual process that depends on various factors, including diet, lifestyle and the severity of your gut imbalances. With consistent effort and the right intervention guided by your physician, you may start noticing improvements in a matter of weeks or months.

The first and most important strategy is to have gut-healthy foods and a balanced diet. Try to include clean and nutrient-dense foods, especially fruits, vegetables, whole grains and fermented foods, to promote a healthy gut microbiome. It’s also best to avoid highly processed or sugary foods or specific items that trigger digestive problems.

High fiber foods are important, as they act as a prebiotic, feeding beneficial bacteria. A diet rich in fiber can support a diverse microbiome, promote regular bowel movements and lower the risk of digestive diseases, including colon cancer.

Consider fiber as the preferred source of nourishment for your gut bacteria. The more variety you include, leafy greens, beans, lentils and berries, the happier your gut microbes are, and the stronger your gut ecosystem becomes.

Exercise also influences gut health. Studies suggest that moderate activity increases the number and variety of beneficial bacteria, while sedentary behavior is linked to less diversity⁷.

Chewing your food slowly, savoring each bite and avoiding rushed meals can reduce stress on the digestive system. Eating patterns that match your body’s natural sleep-wake cycle may also help your gut bacteria stay in balance, which can improve digestion and even sleep. That’s because our eating patterns and the sleep-wake cycle (or the circadian rhythm) play a central role in gut health⁸.

Gut bacteria follow a rhythmic pattern aligned with your body’s internal clock. Emotional eating and disrupted eating patterns, such as those caused by work or travel, can throw off this balance, leading to an imbalance in the microbiome.

Excessive exposure to blue light from devices and lack of vitamin D due to limited sun exposure may also cause the same damage. A depleted microbiome can also harm the sleep cycle.

However, small lifestyle changes can make a difference. A short daily walk, a few minutes of sun or choosing whole foods over packaged snacks give your gut microbes more of what they need to thrive.

The role of probiotics, prebiotics and fermented foods

Fermented foods such as yogurt, sauerkraut and kombucha contain beneficial bacteria (or probiotics) that can help promote a healthy gut microbiome. Including these foods in your diet can contribute to improved digestion and overall gut health.

Probiotics are strains of bacteria or yeasts that are ‘good’ for you and can preserve or accelerate gut health. When your gut microbiome has been disrupted by illness or other factors, repairing it might take time and your physician might recommend supplements in the form of probiotics.

The benefits from probiotics vary depending on the condition of your gut and the specific strain used. Therefore, always talk to your physician before taking an over-the-counter probiotic.

Prebiotics, found in food items such as garlic, onions, leeks and asparagus, act as fuel for probiotics. By combining prebiotics and probiotics, you support your gut from both ends, helping to maintain a diverse and resilient microbiome.

Maintain better gut health for better overall health

Understanding the importance of gut health and its impact on overall well-being empowers you to make informed choices that support a thriving microbiome.

Listen to your gut and nurture it with a balanced diet, probiotics and stress management. With healthy lifestyle habits, you can improve your health from the inside out. Remember, a happy gut can help lead to a happier, healthier you. That’s why, at Mutual of Omaha, we’re committed to providing you guidance on health and well-being that may help you live a fuller, more vibrant life.

Frequently asked questions (FAQs)

Can stress impact gut health?

Yes, chronic stress can disrupt the balance of your gut microbiome and contribute to digestive issues such as bloating, constipation or diarrhea. Managing stress through relaxation techniques and lifestyle changes can help support gut health.

How does gut health affect weight management?

Gut health can impact weight management by influencing metabolism and fat storage. Imbalances in the microbiome have been linked to obesity and metabolic disorders, affecting energy extraction, appetite and fat storage. A balanced microbiome, supported by healthy eating and lifestyle choices, can aid weight management.

Which foods help promote a healthy gut microbiome?

Gut-healthy foods rich in fiber, polyphenols and fermented ingredients can help nourish your microbiome every day. Even minor adjustments, like adding beans to your meals or snacking on nuts, can make a noticeable difference over time.

Expertly reviewed by: Dr. Manoj Pawar, MD, FAAP

Chief Medical Officer, Mutual of Omaha

Dr. Pawar brings over two decades of clinical and executive experience with a focus on preventive care, public health and empowering physicians and patients with the tools they need to live their best lives. Dr. Pawar completed his undergraduate degree at Northwestern University, his medical degree at McGill University in Montreal and his specialty training at the University of Colorado. He’s a Fellow of the American Academy of Family Physician and a member of Delta Omega, the Public Health honor society.

Sources: