Pushing your body too hard or undereating can quietly trigger chronic inflammation.Excess supplements, long fasts and constant stress may raise inflammation markers.Balance, recovery and proper nutrition are key for a healthy routine.

When it comes to daily habits to support our health, it’s easy to assume our routines are helping us. But sometimes, what seems “healthy” on the surface can put too much stress on the body and contribute to chronic inflammation.

Short-term, acute inflammation is a natural defense mechanism, protecting the body from germs and toxins. Chronic inflammation, on the other hand, is an ongoing immune response linked to serious health issues, including diabetes, heart disease, arthritis, obesity and even cancer. In fact, an estimated 129 million people in the United States have at least one major chronic condition.

While many things can contribute to chronic inflammation, daily habits play a major role. That’s why we spoke with registered dietitians to uncover five surprising habits that may be fanning the flame of inflammation. 

1. Overexercising

Overexercising is often admired as the ultimate display of discipline and determination. But pushing your body too hard or too often can do more harm than good. “Overexercising can lead to chronic stress on the body, elevating cortisol levels and causing microtears in muscles that don’t have adequate time to repair [themselves],” says Sara Koreniewski, RD, FDN-P. “This creates a state of systemic inflammation as the body struggles to recover.” This is especially true for intense or prolonged training without sufficient recovery periods.

Studies show that very long, intense workouts trigger the body to release pro-inflammatory markers, such as interleukin-6 (IL-6). Over time, chronic overexercising—or “overtraining syndrome”—can lead to frequent injuries, persistent fatigue, joint pain and a weakened immune system, adds Koreniewski. 

While moderate- to high-intensity exercise supports cardiovascular health, it’s important to prioritize adequate rest and recovery. Instead of chasing harder and longer sessions, Koreniewski recommends a balanced exercise routine that includes rest days, gentle movement like yoga or walking, and recovery strategies such as quality sleep and proper nutrition.

2. Undereating

From skipped meals to very small portions, many people assume that undereating is necessary for weight loss. However, consistently undernourishing your body can quietly work against your health goals. “Undereating deprives the body of essential nutrients needed for cellular repair and energy production, leading to low energy and triggering the cell danger response,” says Koreniewski. The “cell danger response” is a protective stress reaction in cells that, when chronically activated, can increase inflammation. This can lead to chronic inflammation as the body perceives a threat.

Couple undereating with overexercising, and you’ve created a recipe for even more inflammation. “Without enough fuel, your immune system and tissues can’t repair [themselves] properly, while intense exercise adds extra stress and oxidative damage,” says Erin Kenney, M.S., RD, LDN, CPT. “Studies show that not getting enough calories while training can raise inflammation and make recovery harder.”

Both dietitians note that hair thinning, brittle nails, brain fog, irritability, ongoing fatigue, decreased athletic performance and persistent muscle soreness are all signs of energy depletion and underfueling. They recommend working with a registered dietitian to ensure you’re eating enough to meet your activity needs, and practicing mindful eating to reconnect with your body’s hunger and fullness cues.

3. Taking Too Many Supplements

It’s easy to assume that the more supplements you take, the better your health will be. But taking too many supplements may increase inflammation. “Supplements, while intended to support health, can overwhelm the body’s detoxification systems (e.g., liver, gut) and nervous system, especially if they’re unnecessary or poorly matched to your needs,” says Koreniewski. “This can create biochemical imbalances and add stress to an already dysregulated system.”

For example, “high-dose vitamin A can accumulate in the body, disrupting immune signaling and increasing inflammation,” says Kenney. She also notes that high-dose conjugated linoleic acid (CLA) supplements or very high omega-6 intake without sufficient omega-3s may promote pro-inflammatory pathways in some people. Similarly, taking high-dose iron supplements without a clear deficiency or clinical need can increase oxidative stress and trigger inflammatory responses.

Herbal supplements are another area of concern. Inappropriate use of herbal products has been linked with higher risk of liver damage and chronic inflammation. 

“The key is to use supplements only when needed, preferably get nutrients from whole foods and monitor for signs of fatigue, digestive upset or liver strain,” adds Kenney.

4. Overexertion and Chronic Stress

Busy schedules and pushing your mind and body beyond their limits are often framed as being driven and productive—but this approach can backfire. “Constantly pushing past physical, emotional or mental limits activates the nervous system’s fight-or-flight response, leading to dysregulation and chronic stress,” says Koreniewski. She explains that this ongoing stress stress perpetuates inflammation, as the body remains in a heightened state of alert. 

But how exactly is it linked to inflammation? Kenney notes that chronic stress from overworking can increase inflammation by keeping cortisol levels elevated and activating the immune system, leading to increased inflammatory markers, such as C-reactive protein (CRP). For example, “research shows that working more than about 61 hours per week is linked to higher CRP compared with working under 40 hours,” she adds. 

Signs of chronic stress-related inflammation include fatigue, trouble sleeping, mood swings, anxiety, headaches, digestive issues and frequent illness. To combat this, Kenney recommends setting clear work boundaries, prioritizing rest, practicing stress-management techniques like mindfulness or nature walks, and committing to regular personal downtime.

5. Prolonged Fasting

While many people turn to fasting for potential health benefits like weight loss, improved metabolic health and longevity, taking it too far can have unintended consequences. Koreniewski cautions that although short-term fasting may be beneficial for some, prolonged fasting can temporarily increase inflammation.

Research suggests that fasting for 48 hours or longer is associated with higher levels of inflammatory markers, including CRP, IL-6)and tumor necrosis factor-alpha. Importantly, these markers usually return to baseline after refeeding, indicating that the rise in inflammation is likely a temporary stress response rather than permanent damage.

However, certain groups may be more susceptible to inflammation-related effects. People with preexisting conditions, such as heart disease, or those taking oral contraceptives may face additional risks from prolonged fasting., Symptoms such as dizziness, irritability, trouble concentrating and hormonal disruptions can signal that prolonged fasting is placing too much stress on the body.

For those interested in fasting, Koreniewski recommends a more balanced approach, such as gentle fasting windows of 12 to 14 hours, and emphasizes listening to your body’s signals to avoid overdoing it. 

Our Expert Take

Many of the habits we consider “healthy” are often rooted in good intentions. But when taken to extremes, they can place constant strain on the body and quietly contribute to chronic inflammation. True healthy habits focus on what your body can actually sustain, like finding balance with exercise, managing busy schedules and nourishing yourself properly. By making small, thoughtful adjustments that prioritize recovery, balance and proper nutrition, your routine can support your body rather than work against it.