Chronic, low-grade inflammation persists in your body when your immune system stays partially activated even without an infection or injury to fight. Unlike the redness and swelling you get from a cut, this type of inflammation operates quietly, driven by signals from fat tissue, your gut, stress hormones, diet, and even viruses you picked up years ago. It rarely causes obvious symptoms on its own, but over time it contributes to heart disease, diabetes, joint pain, and fatigue. Understanding what’s fueling it is the first step toward bringing it down.
Your Fat Tissue Is an Inflammatory Organ
Body fat, especially the visceral fat packed around your organs, isn’t just energy storage. It actively produces inflammatory signaling molecules. Research comparing visceral fat to the fat just under the skin found that visceral tissue consistently expresses higher levels of inflammatory genes, particularly those coding for IL-6, one of the most potent drivers of systemic inflammation. Subcutaneous fat in obese patients actually showed diminished IL-6 compared to controls, meaning the deep belly fat is the real problem.
This matters because IL-6 and similar signals travel through your bloodstream and put distant organs on alert. Your liver responds by producing C-reactive protein (CRP), a marker doctors use to gauge inflammation levels. A high-sensitivity CRP reading below 2.0 mg/L is considered lower risk, while anything at or above 2.0 mg/L signals elevated cardiovascular risk. Results at 8 or 10 mg/L and above are considered high. If you carry excess weight around your midsection, your visceral fat is likely one of the biggest contributors to whatever inflammation your blood tests show.
Your Gut Barrier May Be Leaking
Your intestinal lining is supposed to be selective, letting nutrients through while keeping bacterial toxins out. When that barrier weakens, fragments of bacterial cell walls called lipopolysaccharides (LPS) slip into your bloodstream. Even at levels far below what would cause a dangerous infection, these fragments trigger your immune system through a receptor called TLR4, setting off a cascade that produces inflammatory molecules like TNF-α, IL-6, and IL-1β.
This condition, sometimes called metabolic endotoxemia, is strongly linked to diet. High-fat diets reduce populations of beneficial gut bacteria, particularly Bifidobacterium. When those bacteria decline, your gut produces less of a hormone that helps maintain the intestinal wall, making it more permeable. The LPS that leaks through then promotes more inflammation, which further damages the gut lining, creating a self-reinforcing cycle. This low-level endotoxemia plays a prominent role in the development of heart and metabolic diseases.
Chronic Stress Disables Your Off Switch
Cortisol is supposed to be your body’s built-in anti-inflammatory brake. When inflammation flares, cortisol signals immune cells to stand down. But under chronic stress, something counterintuitive happens: your cortisol levels may stay normal or even rise, yet your immune cells stop listening to it.
This is called glucocorticoid receptor resistance. A landmark study from researchers at Carnegie Mellon University proposed a model where prolonged stress doesn’t just raise cortisol but changes how your tissues respond to it. Specifically, stress and the inflammatory molecules it generates increase levels of a receptor variant that actively blocks cortisol’s calming signal. The result is an immune system that keeps producing inflammatory responses with no effective brake pedal. Without sufficient cortisol regulation, the duration and intensity of inflammation increases, raising your risk for everything from asthma flares to cardiovascular disease and type 2 diabetes. What matters isn’t how much cortisol you produce. It’s whether your cells can still respond to it.
Your Diet Tips the Balance
The ratio of omega-6 to omega-3 fatty acids in your diet has a direct effect on how much inflammation your body produces. Both are essential fats, but omega-6s tend to fuel inflammatory pathways while omega-3s help resolve them. The modern Western diet delivers these in a ratio around 15:1 or even 20:1 in favor of omega-6, largely because of vegetable oils, processed foods, and grain-fed meat.
Studies manipulating this ratio show clear, dose-dependent effects. In men with metabolic syndrome, meals with an omega-6 to omega-3 ratio of about 18:1 produced significantly more IL-6 (a key inflammatory signal) than meals with a ratio closer to 3:1. Animal research found that a 1:1 ratio produced the least arterial damage and the lowest inflammation, with severity increasing steadily as the ratio climbed. You don’t need to hit a perfect 1:1, but moving the ratio downward by eating more fatty fish, flaxseed, and walnuts while cutting back on processed seed oils can meaningfully reduce the inflammatory load your body carries.
Viruses You Already Carry
Most adults harbor several latent viruses that never fully leave the body. The herpes family is the most common: Epstein-Barr virus (the cause of mono), cytomegalovirus, and herpes simplex collectively infect the vast majority of the global population. These viruses establish lifelong residence in your cells and periodically reactivate, even without causing noticeable symptoms.
Each reactivation event nudges the immune system, and the cumulative effect permanently reshapes your inflammatory baseline. People carrying multiple latent herpesviruses show higher systemic inflammatory markers than those with just one, suggesting the effect is additive. Across all three infections, the same core set of inflammatory signals (IL-6, TNF-α, CRP) stays consistently elevated, reflecting ongoing activation of the same master inflammatory pathway that responds to stress, diet, and fat tissue. You can’t eliminate these viruses, but knowing they contribute helps explain why some people have persistent inflammation even when other risk factors seem controlled.
Air Pollution and Environmental Triggers
Fine particulate matter (PM2.5), the invisible particles from vehicle exhaust, industrial emissions, and wildfire smoke, enters your lungs and triggers inflammation that doesn’t stay local. Inhaling PM2.5 causes lung cells to release inflammatory signals that recruit immune cells into the bloodstream. This leads to damage to blood vessel linings, release of cellular debris into circulation, and elevated levels of adhesion molecules that make it easier for immune cells to stick to artery walls.
If you live near heavy traffic, in an area with regular wildfire smoke, or in a city with poor air quality, this is a daily inflammatory input that compounds over time. It’s one of the less obvious contributors, but air pollution exposure is now recognized as a significant driver of cardiovascular inflammation specifically.
How Exercise Works as an Anti-Inflammatory
When your muscles contract during exercise, they release signaling molecules called myokines directly into the bloodstream. Several of these, including IL-10 and IL-15, have strong anti-inflammatory effects. Interestingly, exercising muscle also releases IL-6, the same molecule that visceral fat produces. But IL-6 from muscle behaves differently: it arrives in a sharp, temporary spike that triggers a subsequent anti-inflammatory response, rather than the constant low-level drip from fat tissue that promotes chronic inflammation.
This is why regular physical activity consistently lowers inflammatory markers over time even without weight loss. The muscle-derived signals actively counterbalance the pro-inflammatory signals coming from fat, stress, diet, and environmental exposure. Sedentary behavior removes this counterweight entirely, leaving the inflammatory inputs unopposed.
Why These Causes Compound
The reason your body may feel overwhelmed by inflammation is that these drivers don’t operate in isolation. They converge on the same core signaling pathway, a molecular switch called NF-κB, which sits at the center of your inflammatory response. Excess calories activate it. Bacterial toxins from a leaky gut activate it. Stress hormones that can no longer suppress it allow it to run unchecked. Latent viruses periodically trigger it. Air pollution feeds into it.
Each individual source might produce only mild inflammation on its own. But when you’re carrying extra visceral fat, eating a high omega-6 diet, sleeping poorly, dealing with chronic stress, and living in a polluted area, these inputs stack. The NF-κB pathway stays chronically turned on at a low level, a state researchers call “meta-inflammation” because it’s driven by metabolic and environmental factors rather than infection. Addressing any single contributor helps, but the biggest reductions come from tackling several at once: improving your diet, moving more, managing stress, and reducing environmental exposures where possible.