Your Microbiome, Your Longevity

By Dr. Kathryn Dundas | Sublime Life

Slow Age with Intention

We talk a lot about mitochondria, hormones, and even genetics in longevity medicine — but one of the most powerful determinants of how you age is living inside you right now: your microbiome.

The trillions of bacteria in your gut don’t just digest food. They influence your immune system, your inflammation levels, your skin, your mood, and even your risk of chronic disease. When this ecosystem is balanced, it supports repair and resilience. When it’s disrupted, it fuels “inflammaging” — low-grade, chronic inflammation that accelerates the aging process.

The good news? Unlike your genes, your microbiome is modifiable. Every bite of food, every night of sleep, every walk in nature is a vote in favour of microbial diversity.

The Role of Fiber: Fuel for Your Microbiome

One of the clearest levers we have to support microbial health is dietary fiber. According to Mayo Clinic’s article “The Functionality of Fiber: Caring for Your Gut Microbiome”, fiber acts as prebiotic fuel— food for beneficial bacteria — helping them thrive and maintain balance.

Fiber supports:

• Growth of microbes that produce short-chain fatty acids (SCFAs) to regulate inflammation and protect the gut lining.

• Healthy motility and regularity.

• Microbial diversity, a hallmark of resilience and healthy aging.

Aim for 25–30 grams daily from fruits, vegetables, whole grains, legumes, nuts, and seeds. Increase gradually to avoid digestive discomfort, and always stay hydrated.

A 7-Day Reset to Support Your Gut + Reduce Inflammaging

Day 1–2: Add Gut-Supportive Foods - Include a serving of fermented food (e.g., ½ cup sauerkraut, kimchi, kefir) if tolerated. If not, use probiotic-rich capsules or dairy-free alternatives.

Day 3: Focus on Fiber -Target 25–30 grams daily (beans, lentils, oats, chia seeds, fruits, veggies). Think: add one fiber-rich food at each meal. This fuels beneficial bacteria that produce anti-inflammatory short-chain fatty acids.

Day 4: Prioritize Sleep Quality -Instead of just hours, track your deep + REM sleep with Oura, Apple Watch, or Whoop. Aim for 1.5–2 hrs deep and 90+ min REM.

Day 5: Move Your Body -Microbiome diversity improves with exercise. Aim for 30 minutes of moderate movement(walking, yoga, cycling) or 15–20 minutes of vigorous activity (intervals, running, strength). Choose what feels enjoyable and sustainable.

Day 6: Nature Reset - Spend 20–30 minutes outdoors in contact with natural environments. Exposure to soil, plants, and fresh air introduces microbial diversity your body thrives on strengthening your system.

Day 7: Reflect + Rewire -Journaling isn’t just mental health — studies show it shifts physiology by reducing stress markers and improving immune response. Write for 10 minutes on changes you’ve noticed in energy, digestion, mood, or resilience this week.

Why It Matters

By being specific — fiber grams, sleep stages, daily minutes of movement, and a journaling practice — you’re giving your microbiome (and your nervous system) the exact cues it needs to reduce inflammation and promote longevity.

This isn’t a fad cleanse. It’s a reminder that small, consistent shifts recalibrate the terrain that drives aging.

Practitioner Pick:

Gut Microbiome + Inflammaging Testing at Sublime Life.

Advanced panels reveal microbial diversity, identify pro-inflammatory patterns, and help us design a personalized nutrition and longevity protocol just for you.

Slow Age with Intention — A Sublime Life

Dr. K Dundas