Gut Health & Immune Support for the Fall Transition

As the days get shorter and the crisp air of fall sets in (a little too soon for my liking!), many of us notice subtle changes in our bodies. Seasonal transitions can challenge both digestion and immunity, making it even more important to pay attention to what we eat and how we care for our health. By supporting your gut, you’re also strengthening your immune system — since our immune function is deeply linked to the gut microbiome.

Let’s talk about how to keep your gut and immune system strong during the fall, practical foods and supplements to add to your diet, and lifestyle strategies to help you feel your best heading into cooler months.

Why Gut Health Matters for Immunity

The gut microbiome — the trillions of bacteria, fungi, and other microorganisms in your digestive tract — plays a major role in regulating immune responses. A diverse, balanced microbiome helps:

• Reduce inflammation

• Support nutrient absorption

• Strengthen the gut lining to block pathogens

• Communicate with immune cells for faster defense

When gut bacteria are disrupted (from stress, poor diet, or illness), your immune system may become weaker — leaving you more susceptible to seasonal colds and infections.

This is exactly why fall can be such a challenge: social commitments increase, school and work for busy families take over, and time to focus on self-care almost seems to disappear.

Fall Foods That Support Gut & Immune Health

Thankfully, fall also brings a bounty of nutrient-dense produce that naturally supports gut and immune function. Here are some foods to add to your plate:

• Pumpkin & Winter Squash – High in fiber and vitamin A, which supports gut health and mucosal immunity.

• Apples & Pears – Packed with soluble fiber (pectin) that feeds healthy gut bacteria.

• Brussels Sprouts & Broccoli – Cruciferous veggies that contain prebiotic fibers and antioxidants.

• Garlic & Onions – Natural antimicrobials with compounds that support both digestion and immunity.

• Fermented Foods (sauerkraut, kefir, kimchi, miso) – Deliver probiotics that keep your microbiome balanced.

Want to learn a bit more about fiber? Check out this great resource from Harvard Health on high fiber foods.

Supplements That May Help

While whole foods should always be your foundation, a few targeted supplements can provide extra support during seasonal transitions:

• Probiotics – Help repopulate the gut with beneficial bacteria.

• Vitamin C - Protects against free radicals that can increase chronic inflammation.

• Vitamin D – Levels often drop as sunlight decreases; critical for immune function.

• Zinc – Plays a key role in immune response and wound healing.

• Omega-3 Fatty Acids – Help lower inflammation that disrupts gut balance.

Curious about supplements in general? Look through my recent blog post that goes more in depth.

Lifestyle Strategies for the Fall

Beyond diet and supplements, a few lifestyle practices make a big difference:

• Stay Active – Regular movement helps regulate digestion and boosts immune cells. If full workouts are difficult to commit to with a hectic schedule, try 2 or 3 ten minute walks after meals.

• Prioritize Sleep – Aim for 7–9 hours to give your immune system recovery time. Keep your sleeping space cool, dark and quiet for the best quality sleep!

• Manage Stress – Chronic stress alters gut bacteria and lowers immunity. Try mindfulness, journaling, or light yoga. Getting in touch with a deeper spiritual or religious practice can also be great.

• Hydrate – Even in cooler weather, your gut needs water to keep digestion running smoothly. Fun fact: coffee and tea count towards your hydration goals!

Stress goes beyond nutrition but it impacts our gut health, too - read through the NIH Fact Sheet on stress to learn a bit more.

Putting It All Together

The transition to fall is a perfect opportunity to reset your nutrition and strengthen your immune system through gut health. By eating seasonal foods, considering supportive supplements, and practicing lifestyle habits that nurture both body and mind, you’ll be better prepared for the months ahead. Don’t be afraid to start small if that’s what you have the bandwidth for.

If you’re ready for personalized guidance, The Rooted Dietitian offers nutrition counseling tailored to weight loss, diabetes management, heart health, and digestive wellness.

👉 Special Offer: Book your first counseling session before September 1st, 2025, and receive 20% off three follow-up appointments in September.