Want to age better? Start with your gut.
Your gut microbiome plays a big role in your health—shaping everything from digestion and immunity to sleep, stress, and more. It’s also a key player in how you age. And your daily habits—from what you eat to how you move—directly affect your gut health.
A healthy gut doesn’t guarantee better aging, more energy, or less inflammation. But research does link many gut imbalances to the opposite. More than half of U.S. adults live with at least one chronic condition, and nearly a quarter manage more than one.
We’re breaking down how your gut evolves through the decades, the health issues to watch for, and the gut-friendly habits that can help you thrive from your 20s through your 80s (and beyond).
Your 20s and 30s
Our gut health journeys begin early—shaped by everything from the microbes we pick up at birth to the environments we grow up in.
Our twenties and thirties are important windows as the microbiome stabilizes and begins responding to the demands of adult life. Whether raising kids, managing a health issue, or using tech to stay on top of your health, this stage of life can be a lot. There’s stress. There’s change. And it all adds up.
Unhealthy patterns often take root during this time, setting the stage for health issues later on.
What’s happening in your gut
Research shows that around this time, one group—Bacteroides—often crowds out the rest [1].
Bacteroides help break down carbs and proteins—like the ones in that quick chicken and pasta dinner you toss together. In moderation, they’re helpful. But if Bacteroides become too dominant—especially the toxin-producing types like Bacteroides fragilis—they can edge out beneficial microbes. Sometimes, that contributes to inflammation and metabolic issues.
To support healthy aging, you want gut diversity —a characteristic of a healthy microbiome. Eating a whole-food diet with fermented foods is an easy way to boost it. Fewer Bacteroides and more variety may help your gut stay resilient and support longevity [1].
Nonstop days and sleepless nights raise cortisol, your body’s main stress hormone. Cortisol influences how your gut, immune system, and brain work together to support your emotional and physical well-being [2].
Other hormones are also at play. Pregnancy, postpartum shifts, and monthly cycles can all affect gut diversity [3], [4].
Common gut health challenges in your 20s and 30s
- Leaky gut from a heavily processed diet: Junk food can weaken your gut’s protective lining. Toxins or undigested food can slip into your bloodstream and trigger inflammation. Tiny Health’s gut tests include markers that may help you flag early signs of this.
- Gut stress from frequent drinking: People in their 20s and early 30s tend to drink alcohol more frequently—often in social settings—which can throw off your gut and contribute to inflammation over time.
- Low microbial diversity from restrictive diets: Extreme low-carb diets like keto or carnivore can reduce microbial diversity—something your gut needs for healthy aging [5].
- Irritable Bowel Syndrome: Stress, diet, hormones, and even sleep patterns can all influence IBS symptoms, which include bloating, discomfort, and irregular bowel movements.
Gut-friendly habits for this stage of life
- Eat a whole-food diet with fermented foods and a variety of plant-based fibers and polyphenols. This feeds good bacteria for a balanced gut.
- Walking is one of the simplest ways to support your long-term health. Getting around 8,000 steps a day is linked to a 40–50% lower risk of dying early [6].
- Prioritize your sleep. Rest supports your gut, brain, and mood. Sleep is key for metabolic and immune health, helping you lower the risk of chronic conditions.
- Make time to de-stress. Try a simple breathing exercise—inhale for four seconds, hold for five, and exhale for six. It’ll help regulate your nervous system.
- Be mindful about antibiotics: Sometimes, they’re essential. Because they can wipe out good bacteria, you don’t want to take them unless it’s necessary.
Your 40s and 50s
In your 40s and 50s, life is often busy—career, family life, and routines that leave little room for self-care. You may start to notice a shift in your energy, digestion, and metabolism. Even how you handle stress might start to change. Your gut plays a big role in those changes.
Whether you're adjusting your diet, lifting weights, or focusing on better sleep, your habits during this stage impact your gut health—and how you feel throughout this time in your life.
What’s happening in your gut
A Nature Metabolism study shows that in people aging well, gut microbes become increasingly unique [1].
As Bacteroides decline, a new group of microbes populates your gut—including ones that break down foods like turkey, eggs, and nuts into compounds called tryptophan-derived indoles. Indoles, more common in diverse microbiomes, help lower inflammation [1]. That matters since lower inflammation can mean less heart disease, joint pain, and brain fog.
Hormone shifts also shape your gut during these years. During menopause, the decline in estrogen and progesterone is associated with reduced gut microbial diversity and changes in gut function that may impact gut barrier integrity and systemic inflammation [3], [4].
Testosterone declines gradually in men. Research shows that inflammation, especially in an imbalanced gut, can suppress testosterone [7].
Our metabolism also naturally slows down. It’s likely why many health-conscious adults in midlife have tried keto or carnivore diets. Without enough fiber, these diets can stress your gut.
Less fiber means your gut produces fewer short-chain fatty acids (SCFAs) like butyrate—compounds that support a strong gut lining and keep inflammation levels in check [8].
A high-fat diet can also encourage an overgrowth of Bilophila, a bacteria linked to inflammation and gut imbalance in mice [9].
Common gut health challenges in your forties and fifties
Leaky gut and inflammation
Your gut lining often becomes more porous with age. Unwanted particles in the bloodstream can trigger inflammation and digestive issues. Gut tests that include markers like Hexa-LPS and H₂S producers can help you identify early stress in your gut.
Heart health risks
Women under 50 are at higher risk of dying from heart attacks than men [10]. One emerging area of interest is the gut. A disrupted microbiome may increase inflammation and raise levels of TMAO, a compound linked to heart disease [11].
Everyday digestive issues
Bloating, reflux, constipation, and gas are often signs your gut isn’t working as well as it could. These issues become more frequent in midlife but are commonly brushed off.
Colon cancer
Colorectal cancer rates are rising among people under fifty. Some research shows that microbial imbalances—including changes in diversity and increases in certain bacteria—can appear even before symptoms emerge [12], [13].
Gut-friendly habits for this stage of life
- Keep moving: From achieving your goal weight to uplifting your mood to supporting your heart health, walking is one of the simplest ways to care for your body—and your gut—as you age. Plus, it's gentle on your joints. Also, a balanced gut helps regulate hunger hormones like ghrelin and leptin, which play a role in how your body holds onto weight.
- Challenge your family to eat at least 30 different plant foods each week: Think color, variety, and flavor—eat the rainbow and add more herbs and spices to your meals. Make your own tea with fresh herbs you have on hand.
- Try intermittent fasting: Some midlifers find that intermittent fasting helps with weight management. One study showed that it may spark autophagy, the body’s natural cell cleanup process. It may also help lower inflammation and support better energy use [14]. In a mouse study, fasting also increased Akkermansia muciniphila, a bacteria linked to better metabolism and higher GLP-1 production [15], [16].
- Keep sweets in check: Cut back on added sugar during the week to leave room for the moments that count. If dessert has become a nightly thing, try choosing one or two nights each week instead.
- Stay on top of screenings/preventive care: Colonoscopies are key when it comes to gut health and aging. They help catch early signs of colorectal cancer—especially as rates rise in younger adults.
Your 60s and 70s
As we age, chronic inflammation like cardiovascular disease, type 2 diabetes, and obesity become more common. When daily movement drops and processed foods take over, longevity can take a hit—especially with long-term medications in the mix.
What’s happening in your gut
In your sixties and seventies, your gut remains responsive—even to small, steady changes. Research shows that a gut able to adapt—through improvements in diet, movement, and stress—is linked to better health outcomes later in life. Older adults whose gut microbiomes changed more over time tended to live longer [1]. They also had lower cholesterol, walked faster, and showed healthier blood markers.
A more diverse, adaptable gut may help support healthier aging by reducing inflammation [17].
What drives these microbiome shifts with age? Sometimes, it’s one small thing, like starting a medication. Other times, it’s cumulative. Your energy’s low, so you stop walking in the morning. Instead of making fiber-rich, colorful meals, you reach for something processed. Over time, these changes can throw your gut off balance—and show up in different ways as you age.
Some of these changes can increase gut permeability and lead to inflammaging: the low-grade, chronic inflammation tied to aging and disease [18].
Common gut health challenges in your 60s and 70s
Leaky gut and inflammation
With age, protective bacteria like Bifidobacterium, Lactobacillus, and Ruminococcus, which support the gut barrier, often decline [18], [19]. Pro-inflammatory microbes like Enterobacteriaceae (linked to cognitive impairment) rise [20]. These imbalances can weaken the gut lining and trigger long-term, low-level inflammation [18].
Mood, sleep, and cognition changes
The gut plays a key role in making neurotransmitters like serotonin. When the microbiome shifts, it can affect how you sleep, feel, and process your thoughts [3], [21].
Constipation, memory, and movement disorders
In Parkinson’s disease, constipation often shows up before movement symptoms begin. One study found that about 1 in 4 people with Parkinson’s had constipation before any motor changes. It’s also common in Alzheimer’s—roughly 25% of people with dementia experience constipation.
While the connection isn’t fully understood, research suggests that gut changes may play an early role in brain-related diseases. In Alzheimer’s, for example, toxins from the gut may contribute to the buildup of plaques in the brain linked to cognitive decline [22].
Weakened immune function
The gut plays a major role in your immune system—some estimates say around 70% of immune cells live there. Our immunity naturally weakens with age. A disrupted microbiome may further reduce your ability to fight off illness.
Gut-skin axis and aging skin
The gut and skin are connected through the gut-skin axis, where gut microbes help regulate inflammation, immune function, and hormones that influence your skin health. As you age, a less diverse microbiome and lower levels of short-chain fatty acids (SCFAs) may contribute to visible skin changes—like dryness, thinning, and reduced elasticity. Hormone shifts during menopause may make these effects more noticeable [23].
Gut-friendly habits for this stage of life
- Spend time outdoors: Even a short walk after dinner can support digestion and blood sugar balance. Gardening or doing a few light stretches outside also exposes you to beneficial microbes and can lift your mood.
- Mix up your meals—and share them: Focus on foods rich in prebiotics and resistant starch—like oats, lentils, barley, green bananas, or cooked and cooled potatoes.
- Watch for hidden sugar: Your body may process sugar differently at this age. Sauces, condiments, and packaged snacks often carry more added sugar than you’d expect.
- Get personalized support: Whether you're managing a chronic condition, looking to support immunity, or hoping to improve digestion, a microbiome specialist can help you navigate the best option for your gut health. They’ll work with you to create a personalized plan based on your diet, lifestyle, and supplement needs.
- Keep your brain active: Your gut and brain are closely connected. Reading, puzzles, or learning something new can help support that connection and promote long-term well-being.
Your 80s and beyond
The gut continues to change well into your 80s. Even in later years, it remains a powerful ally. Simple choices—like eating more fiber and staying socially connected—can support gut health and aging.
These habits are common in regions known for their high number of centenarians—people who live to 100 and beyond—like Okinawa and Sardinia.
What’s happening in your gut
Those in their 80s and 90s who are aging well have more unique microbiomes. Fewer Bacteroides and more diversity are linked to better life expectancy [1].
Your gut’s ability to manage proteins declines—a process called proteostasis. When proteins are damaged and aren’t cleared out, they can disrupt your gut lining and contribute to leaky gut and inflammation [24].
Aging also affects mitochondria—our cellular powerhouses—which can further fuel inflammation and poor health [25].
Common gut health challenges in your eighties and beyond
Reduced gut diversity
As we age, microbiome diversity often declines, especially with restrictive diets or long-term medication use [26]. This shift may reduce resilience and raise the risk of bowel inflammation and cognitive decline.
Leaky gut
Many older adults experience a breakdown in proteins that seal the gut lining. This can raise the risk of a leaky gut, chronic inflammation, and proteostasis (the gut’s ability to clear damaged proteins) [27].
Sedentary habits
Lack of movement can impact your gut composition and immune function, raising the risk of chronic conditions that affect your quality of life.
Gut-friendly habits for this stage of life
- Eat well: Stick to simple, nourishing foods like cooked veggies, yogurt, lean proteins, and berries. Smaller meals and staying hydrated can also help digestion.
- Stay active: Gentle movements like walking or light stretching can support balance and mobility. Even 10–15 minutes a day makes a difference.
- Protect your sleep: As you age, your gut may produce fewer short-chain fatty acids (SCFAs), which support a strong gut lining and help manage inflammation. Poor sleep can lower SCFA levels even more and weaken the gut’s natural barrier. A steady bedtime and calm evening routine can support better sleep and gut health.
- Stay connected: Phone calls, coffee chats, and time with family and friends can lift your mood and help keep your mind sharp. In-person connections—when possible—can be especially meaningful.
- Medications and supplements: What worked well in your 70s might need adjusting in your 80s. Check with your practitioner or get a gut health test to see if adding supplements to your daily routine might be helpful.
Better aging: The long game
We’re just beginning to understand how the gut shapes the way we age. What’s clear so far? Your lifestyle matters. Small, steady habits can help you feel stronger, clearer, and more resilient—in the moment and as you age.
These days, there are more ways than ever to personalize your wellness routine. Whether you’re making a nourishing meal for your family, turning to Traditional Chinese Medicine to ease IBS, or using a tracker to monitor sleep and steps, taking charge of your longevity has never been easier.
Supporting your gut—at any age—is a powerful form of self-care. Not sure where to start? A Gut Health Test can help you address gut imbalances early and set you on the path to aging well.
