How Stress Affects Your Health

Stress is something nearly everyone experiences, but few people realize just how deeply it can affect the body. To help explain what stress does physically and mentally, Franciscan Health psychiatrist Kenn Vattathara, MD, shares insight from both medical research and clinical experience.

Dr. Vattathara practices at Franciscan Behavioral Health’s outpatient clinic in Munster and works closely with patients managing stress, anxiety and chronic conditions.

Key Takeaways: Stress & Your Health

• Stress is protective in the short term but harmful when it becomes chronic. The body’s fight-or-flight response helps in emergencies, but prolonged activation can damage multiple organ systems.
• Ongoing stress can worsen heart disease, diabetes, autoimmune conditions, digestive disorders and immune function.
• Many people feel stress physically before emotionally. Muscle tension, headaches, digestive issues, skin flare-ups, sleep problems and fatigue are common physical signs.
• Managing stress early can protect long-term health. Small, consistent strategies like movement, mindfulness, quality sleep and social connection can reduce stress-related damage and improve resilience.

What Is Stress

Stress is your body’s natural response to pressure or perceived threat, whether that threat is physical, emotional or mental.

How Your Body Reacts To Stress

Stress activates powerful systems in the body that are designed to protect us in moments of danger. When those systems remain turned on for too long, the consequences can affect the organ system.

“When you really think about it from the brain,” Dr. Vattathara said, “the brain’s hypothalamus acts like a control tower. It immediately activates your body’s stress response system.”

That response triggers the release of stress hormones, primarily adrenaline and cortisol, which initiate a cascade of changes throughout the body. In the short term, these changes are beneficial.

“In the acute phase, adrenaline increases your heart rate. It elevates your blood pressure and boosts energy,” he said. “It also helps mobilize glucose into your bloodstream.”

Cortisol, the body’s primary stress hormone, works alongside adrenaline by flooding the bloodstream with additional glucose and temporarily suppressing non-essential functions like digestion and reproduction.

“This is your fight-or-flight system,” Dr. Vattathara said. “Acute stress, when it’s resolved quickly, is actually protective.”

When Stress Becomes Chronic

Problems arise when the stress response never fully shuts off.

“When people talk about stress,” Dr. Vattathara said, “it’s when these systems are activated chronically, when that stress response is continually activated without any sort of adequate recovery.”

Over time, chronically elevated cortisol and adrenaline levels begin to take a serious toll. Persistent inflammation develops, immune function weakens and the risk for disease increases.

Research from the National Institutes of Health shows that chronic stress can disrupt nearly all of the body’s systems —cardiovascular, digestive, endocrine and immune.

Stress And Chronic Illness

While stress does not directly cause disease, it plays a significant role in worsening or accelerating many conditions.

“I’m not trying to say that stress alone is the one that causes these diseases,” Dr. Vattathara said. “Genetics, lifestyle factors and environmental factors all play a role, but stress also acts as a powerful catalyst.”

Dr. Vattathara said studies have shown strong links between chronic stress and cardiovascular disease. Persistent stress contributes to inflammation in the arteries and can promote plaque buildup through a process known as atherosclerosis.

Stress is also closely associated with gastrointestinal conditions such as peptic ulcers and ulcerative colitis, where stress alters stomach acid levels. In people who are overweight, chronic stress can significantly increase the risk of developing type 2 diabetes by altering insulin needs and glucose metabolism.

Autoimmune diseases, including rheumatoid arthritis, psoriasis, lupus and multiple sclerosis, may also flare during periods of prolonged stress.

Physical Symptoms Of Stress

Many people experience stress physically before recognizing it emotionally. Chronic muscle tension is common, especially in the neck, shoulders, back and jaw.

“If it’s chronic, you can have muscle aches and pains,” Dr. Vattathara said. “A lot of that chronic tension is one of the primary drivers for tension-type headaches and migraines.”

Stress can also affect the digestive system, leading to bloating, nausea and diarrhea. From a dermatological standpoint, stress can trigger rashes, hives and acne, while worsening conditions such as eczema and psoriasis.

Respiratory symptoms may occur as well, particularly during panic attacks, when shallow breathing and shortness of breath become prominent.

Stress, The Heart And Blood Pressure

The cardiovascular system is especially sensitive to chronic stress.

“Adrenaline increases your heart rate, increases your blood pressure and increases your need for energy supplies,” Dr. Vattathara said.

Over time, this increased demand raises the body’s need for oxygen and can lead to heart palpitations, chest pain and shortness of breath.

Immune Suppression And Stress

The immune system is another major casualty of prolonged stress.

“Chronic stress reduces T-cell proliferation, decreases natural killer cell activity and impairs antibody production,” Dr. Vattathara said.

This immune suppression has real-world consequences. People under chronic stress experience more frequent colds and flu, slower wound healing and reduced responses to vaccinations. A Carnegie Mellon University study found that individuals under high stress were significantly more likely to develop respiratory infections after exposure to cold viruses.

Sleep, Energy And Cognitive Function

Stress also disrupts the body’s natural sleep-wake cycle. Cortisol typically peaks in the morning and gradually declines throughout the day, allowing melatonin to rise at night. Chronic stress disrupts this rhythm.

“Stress prolongs the time it takes people to fall asleep and fragments sleep with frequent awakenings,” Dr. Vattathara said.

Even when sleep occurs, the brain spends less time in restorative REM and deep sleep.

Over time, this leads to fatigue, impaired concentration and reduced cognitive performance. Research shows that chronic stress negatively affects attention, memory consolidation, decision-making and emotional regulation.

Stress, Hormones And Weight Gain

Cortisol plays a central role in stress-related weight gain.

“When stress becomes chronic, your adrenal glands continuously produce elevated levels of cortisol,” Dr. Vattathara said. “That sustained elevation fundamentally alters your metabolism.”

High cortisol levels increase appetite and cravings, slow metabolism, promote muscle breakdown and interfere with insulin regulation, making weight gain more likely and weight loss more difficult.

When To Seek Medical Care

Recognizing when stress symptoms require medical attention is critical.

“If you ever have chest pain especially if it’s severe, crushing or radiating to your arm, jaw or back call 911 or go to the ER,” Dr. Vattathara said. “Severe shortness of breath, irregular heartbeat or neurological symptoms also warrant immediate evaluation.”

“If your stress is getting to the point where you’re not able to keep yourself safe, or you’re having thoughts of self-harm or suicide, seek emergency care immediately,” he added.

For persistent but non-emergent symptoms, he recommends seeing a primary care provider or mental health specialist for evaluation and referral.

Healthy Ways To Manage Stress

There is strong evidence supporting several stress-management strategies, including mindfulness, meditation, gentle yoga and deep breathing exercises that activate the parasympathetic nervous system.

Physical activity is also powerful.

"Anything that increases baseline heart rate can enhance emotional resilience over time,” Dr. Vattathara said.

Social connection, good sleep hygiene, time management and cognitive behavioral strategies all play important roles as well.

“The key thing I tell all my patients,” he said, “is to start small, be consistent and personalize your approach. Don’t wait until you’re overwhelmed.”

Managing Stress In An Uncertain World

In times of national and global uncertainty, stress can feel overwhelming. Dr. Vattathara emphasizes compassion both for oneself and for others.

“Managing stress is difficult, but being mindful of what others may be going through can help,” he said. “Knowing when to seek help, maintaining healthy routines and staying connected to supportive people can significantly reduce the long-term impact of stress.”

Stress is a natural part of life, but it doesn’t have to define health outcomes. With awareness, early intervention and the right support, individuals can protect both their mental and physical well-being, even in the most challenging times.