Chronic inflammation: the quiet fire behind so much of your health

Your body's best repair system has a quiet twin that never switches off. Here's how to tell them apart, what keeps the second one burning, and what actually turns it down.

Chronic inflammation is one of the most important things I teach, because it's the same repair system that saves your life after an injury, just left switched on for months or years. It doesn't hurt. It doesn't swell. Most people can't feel it at all. And that's exactly why it's worth understanding.

Two kinds of inflammation: the fire brigade and the ember

I've kept very few of my books from medical school. One is a worn pocket companion to the pathology textbook I studied in the fall of 1993. Chapter two is on inflammation, and the first thing it does is split it into two buckets: acute and chronic.

You already know acute inflammation. You sprain your ankle, and it gets warm, red, swollen,n and sore. Underneath, the blood vessels open up so parts of the blood can get into the tissue. White blood cells move in. There's clotting, then cleanup, then rebuilding. And within a few days or a week, the whole operation packs up and goes home.

That's the fire brigade. It shows up, puts out the fire, and leaves. This is the inflammation that's your friend, and basically what keeps you alive.

Chronic inflammation isn't the fire brigade. It's a smoldering ember that essentially never goes out. Low heat, all the time, everywhere, with the immune system on alert even though there's no real emergency. A widely cited review in Nature Medicine made the same distinction: short bursts of inflammation are critical for surviving injury and infection, while social, environmental,l and lifestyle factors can promote a low-grade, body-wide inflammation linked to several of the leading causes of disability worldwide (Furman et al., 2019).

The alarm nobody turns off.

Imagine your house alarm goes off because a burglar tried to break in. The alarm does its job. It makes noise, summons help, scares the intruder away. But then nobody ever turns it off.

The alarm keeps ringing. And the constant vibration starts to damage the house itself: little stress fractures in the walls, systems failing one by one. The original threat may be long gone, or there may never have been one, but the signal never stops.

In your body, that ringing is a family of chemical messengers called cytokines. Think of them as text messages sent out by immune cells. In a sprained ankle, those texts organize the repair. When they never stop, they irritate the lining of your blood vessels and garble the hormonal messages your cells rely on.

And there's no swelling, no fever, no pain to warn you. At first, it shows up only in blood markers. It's like a smoke detector that goes off for burnt toast: built for real fires like infections and wounds, but reacting to things it was never designed to meet.

What keeps the fire lit

The modern world is full of things that keep the alarm stuck in the on position, and most of them are invisible. In class, I focus on four.

Visceral fat deserves a closer look, because it's one of the biggest logs on the fire. In one small study, researchers sampled blood leaving the visceral fat of 25 people with severe obesity. It carried about 50% more of the inflammatory messenger IL-6 than blood elsewhere, and those levels tracked with a standard whole-body inflammation marker (Fontana et al., 2007). It's an older study in a narrow group, but it shows the mechanism clearly: that fat is actively feeding the smolder.

Stress works through the same alarm. Thousands of years ago, a lion chased you, your body released a surge of chemicals, you ran, you used them up, and you went back to baseline. Today it's as if the lion chases you all day, except you never run it off and never get a break. My teacher called this the false emergency state, and the human body was never meant to live in it.

Sleep is like a city that never gets its trash picked up. A large review of 72 studies, covering more than 50,000 adults, found that disturbed sleep was associated with higher levels of inflammatory markers like CRP and IL-6 (Irwin et al., 2016). To be fair to the evidence, that's an association, and short-term lab experiments that deprived people of sleep didn't show the same clear shift. But the long-term pattern is hard to ignore.

One fire, many rooms

When we studied high blood sugar in class, I described the body as a house with different rooms. Chronic inflammation is like rust spreading through the infrastructure of that house. It doesn't destroy anything overnight. It weakens things slowly, and it looks a little different in each room.

The blood vessels. You know how spilled soda leaves the floor sticky? Something similar happens inside your blood vessels when blood sugar runs high (more on that in why your blood sugar spikes). Inflammation adds to it, making the lining rough so cholesterol can get trapped. That's a big part of why doctors now look at inflammation alongside cholesterol when they think about heart health.

The insulin signal. Insulin is a message that tells your cells to take in fuel. Inflammatory messengers interfere with it, like a text that never quite gets through.

The brain. Your brain has its own immune cells, called microglia, the guards that protect your nerve cells. When the alarm is stuck on, those guards can become overprotective, and over decades, that's linked to brain aging.

Your muscles. Believe it or not, inflammation can blunt your ability to build muscle, even when you're doing everything right in the gym.

Your mood. This one surprises people most, and it's a big enough topic that I gave it its own write-up: inflammation and mood.

So these aren't five separate problems. In a lot of ways, it's one fire that looks different in each room. They tend to run together, and in my practice, when someone works on one, the others often start moving with it.

What actually turns it down

Here's the good news. Chronic inflammation isn't permanent. The fire can be turned down, sometimes a lot. We're not talking about supplements or trends. We're talking about the levers with real evidence behind them. Think of them as the real firefighters.

Remove the smoldering log. Losing visceral fat is one of the most powerful anti-inflammatory moves you can make. My favorite way to target it is a periodic fasting-mimicking approach, popularized by the scientist Walter Longo: five days a month of reduced calories, repeated for a few months. I've coached many people through it, but it isn't right for everyone, so talk with your own doctor first. Steady everyday habits reduce visceral fat over time too.

Move your muscles. Every time a muscle contracts, it sends its own text messages into the bloodstream, many carrying anti-inflammatory instructions to other organs. A meta-analysis of 83 trials found that exercise training lowered CRP, a key inflammation marker. The drop was bigger when people also lost body fat, but it showed up even when they didn't lose weight (Fedewa et al., 2017).

Take out the ultra-processed food. Chips and snacks made with processed oils, excess sugar, white flour, and alcohol. Remove first, then add.

Sleep as it matters. Because it does. It's your body's built-in cleanup crew.

Take real downtime. I tell my patients everyone needs 30 to 40 minutes of active downtime every day, while awake. Not a TV show. Focusing on your breath, a long warm bath where you're truly calm, or a guided-imagery recording. You can't be on all day and count on sleep as your only rest.

What to put on your plate

Then add the foods that calm the fire. Oily fish like salmon, sardines, and mackerel bring omega-3 fats. Extra virgin olive oil carries a compound called oleocanthal, though you don't need it to do this well.

Probably the most important piece is an acronym from Dr. Joel Fuhrman: G-BOMBS. Greens, beans, onions, mushrooms, berries, and seeds, ideally every day. They're rich in polyphenols, the plant compounds that help quiet the body's inflammatory switches. Of all the eating patterns I've guided people through, the one built around G-BOMBS is where I've seen people feel the biggest difference.

Add fermented foods for your gut, and cook with turmeric and other spices. A simple rule of thumb: if your food is naturally colorful, you're getting polyphenols. And this is the reason why a plate of real food can do what no single pill can.

Questions I get about this

How do I know if I have chronic inflammation?

Since you can't feel it early on, a blood test is the best window. Ask your doctor about high-sensitivity CRP, often written hs-CRP. It's one of the most sensitive markers of inflammation, and I think everyone should know their number.

If I can't see or feel visceral fat, how do I know I have it?

The easiest way is a DEXA scan. Many people know it as a bone density test, but it also measures visceral fat and overall body fat accurately, with a very small dose of radiation. Sometimes you can see it, too: a large, firm belly without much fat on the outside usually means the fat is on the inside.

I started exercising, and the scale hasn't moved. Is it working?

Very likely, yes. Inflammation markers can come down with exercise even without weight loss. The scale can be slow to move, but your muscles start sending those messages right away.

Do I need to replace everything in my bathroom?

You could go crazy with those lists of everyday products. There are toxins in our environment, and clean versions exist of most things. Start with food, movement, sleep, and stress. If your labs show inflammation, that's a good time to learn more.

References

1. Furman D, et al. Chronic inflammation in the etiology of disease across the life span. Nature Medicine. 2019. PubMed
2. Fontana L, et al. Visceral fat adipokine secretion is associated with systemic inflammation in obese humans. Diabetes. 2007. PubMed
3. Irwin MR, et al. Sleep disturbance, sleep duration, and inflammation: a systematic review and meta-analysis of cohort studies and experimental sleep deprivation. Biological Psychiatry. 2016. PubMed
4. Fedewa MV, et al. Effect of exercise training on C-reactive protein: a systematic review and meta-analysis of randomised and non-randomised controlled trials. British Journal of Sports Medicine. 2017. PubMed