Have you been feeling tired (even after sleeping a full night), bloated, foggy, achy, irritable — or just off — for no clear reason? On their own, these symptoms are easy to ignore because they don’t seem serious. But when several show up — and stick around — it could signal something deeper.
Finding the cause can be tricky because the symptoms don’t seem to be connected. Occasional gut discomfort here. A headache there. Trouble focusing. Fatigue. What’s driving them all?
According to gastroenterologist and gut health expert Dr. Will Bulsiewicz, this feeling of “everything but nothing obvious” is very common. After reviewing years of research, he’s identified more than 130 health conditions linked to chronic, low-grade inflammation — affecting everything from metabolism and immunity to mood and mental health.
When inflammation overstays its welcome
Despite its bad reputation, inflammation can be good. Acute, short-term inflammation helps your body heal cuts, fight infections and recover from stress. It’s designed to turn on, do its job and turn off.
The trouble starts when it doesn’t.
Chronic, low-grade inflammation is subtle. It may not cause a fever or force you into bed, but it can wear down the body over time. Symptoms like fatigue, bloating, headaches, joint pain, brain fog, poor recovery and mood changes can all be signs of an immune system stuck on simmer.
The gut microbiome connection
As Dr. Bulsiewicz puts it, “You cannot separate the gut microbiome from the immune system — they rise and they fall together.” About 70% of your immune system lives in your gut. It’s the command center where trillions of microbes help train immune cells, protect the gut lining and produce compounds that regulate inflammation.
When the gut microbiome is healthy, it helps keep the immune system calm and focused. But chronic stress, irregular sleep and ultra-processed foods can strain the gut barrier. When that barrier weakens, the immune system gets triggered more often than it should, keeping inflammation quietly switched on. This can not only cause sore muscles and joints, but can also affect energy, digestion, focus, mood, skin quality and recovery — sometimes all at once.
How to help your immune system simmer down (without overhauling your life)
The goal is to help your immune system relax when there’s no real threat to it.
A good place to start is by asking, “What’s one small thing I could do this week to better support my gut and immune system?” Because when that system settles, the rest of the body often follows.
Try adding one of these to your menu
What you eat today can affect your gut microbiome by tomorrow, and your gut barrier fully renews itself every three to five days.
Fiber: Fiber feeds gut microbes that produce short-chain fatty acids — some of the most powerful anti-inflammatory compounds we know.
Colorful plants: Polyphenols, the compounds that give plants their color, support microbial diversity and reduce inflammation. Your microbes help unlock their benefits, so variety matters.
Healthy fats: Extra-virgin olive oil, nuts, seeds, avocados and omega-3s support anti-inflammatory pathways and gut health.
Fermented foods: Yogurt, kefir, kimchi and sauerkraut can increase gut diversity and reduce inflammatory markers in as little as 10–12 weeks.
Get more tips about nibbling your way to reduced inflammation.
Consider doing one of these things
Consistent sleep and meal timing help regulate immune activity. Eating earlier in the day within a regular 10–12-hour window is associated with better metabolic and inflammatory responses.
Connection, time outdoors, gentle movement, breathing and calm moments activate your body’s rest-and-repair system — which your gut and immune system rely on.
Even small shifts, like swapping one processed snack for something fiber-rich or eating one meal slowly without electronic screens, can help signal “rest and digest” instead of constant alert.
At the end of the day, this isn’t about chasing symptoms or finding a single fix. It’s about supporting the systems that help your body regulate itself, because when those systems feel supported, scattered symptoms that once felt unrelated often begin to make a lot more sense.
Tackle the topic during your next checkup
Your health status may spark other actions you can take to calm inflammation. Set a reminder for yourself to ask your provider about this during your next checkup or wellness care visit.
Source: Bulsiewicz, W., interviewed by Wolf, J. (2026). 4 foods that heal your gut and reduce inflammation (in as little as 24 hours!) ZOE Science & Nutrition Podcast. Apple Podcasts. https://podcasts.apple.com/us/podcast/zoe-science-nutrition/id1611216298?i=1000746200957