How Stress Affects the Body

How Stress Affects the Body
Natalie Stein

Exercise, Fitness & Nutrition Expert | Lark Health

We hear a lot about stress, about too much stress, and about being stressed out. You may know of people who (or you yourself may) stress-eat, lie awake in bed because of stress, have stress-induced headaches, and be moody because of stress. But what is stress, how does it affect the body, and what can you do about it?

What Is the Stress Response?

What happens when you are facing a challenge? Let’s say you have a major exam, or you are about to present a proposal to your CEO. As nerves increase, your heart may pound faster, your breathing may quicken and become deeper, and you may feel butterflies in your stomach. 

Then, your concentration increases. Your senses strengthen as everything seems clear and in slow motion. You perform flawlessly. Then, exhaustion sets in.

What just happened? The stress response kicked in. That same “flight or flight” response is just what our ancestors counted on when facing threats, such as coming face to face with a wild animal. It happens when the central nervous system activates. The hypothalamus causes the adrenal glands to release stress hormones called cortisol and adrenaline or epinephrine.

Effects of Stress on the Body

The stress hormones affect your body from top to bottom. These are some effects of cortisol and adrenaline.

  • Increased heart rate, deeper, faster breathing, and increased blood pressure to increase the flow of oxygen through the body so muscles can be ready to work and the brain can focus better.
  • Release of glucose (sugar) into the blood to fuel muscles and the brain for increased awareness and heightened sensation.
  • Tensing of muscles so they are ready to work, fight off injuries, and feel less pain.

Why Acute Stress Can Be Good

These are all parts of what is called the acute stress response. It is the response to a single event. It could be a presentation, exam, doctor’s appointment, athletic competition, car accident, or encounter with a hungry saber-toothed tiger. Stress lets you rise to the occasion.

Chronic Stress: Too Much of a Good Thing

Acute stress can be a good thing because it lets you perform better, but stress that continues for long periods of time becomes chronic. Chronic stress may come from worries about health, finances, jobs, children, and relationships, to name a few.

Chronic stress can increase health risks through many of the same pathways that acute stress lets you face challenges. For example:

  • Increased blood sugar gives you energy to fight tigers, but raises risk for diabetes when it stays high.
  • Inflammation helps your body heal injuries, but increases risk for heart disease and other conditions when it continues throughout your body.
  • Prolonged exposure to cortisol and adrenaline can weaken the immune system and cause more infections. These can include common respiratory infections such as colds, as well as H. pylori infections, which are linked to ulcers. 
  • Rapid heart rate and breathing let you push through fatigue and increase concentration, but too much anxiety may increase risk for indigestion.
  • Tensed muscles get you ready to push the elderly lady out of the way of an oncoming car, but prolonged tension can cause headaches, back and neck pain, and aches throughout the body.
  • Higher blood pressure lets your body get more oxygen during acute stress, but high blood pressure too often can cause hypertension.
  • Getting amped up to achieve can serve the purpose, but being amped up too often can lead to burnout or exhaustion.

Stress Management

Too much unmanaged stress can be harmful, but reducing stress where possible and managing the rest can keep it from being overwhelming. The right amount of stress, managed well, can even be healthy! 

Reducing stress may include letting go of things you cannot control. If weight loss attempts are stressing you out, for example, it may be time to “let go” of what the scale says or what anyone else says about your weight. Instead, something you can control is what goes into your mouth.

For stress that you cannot get rid of, stress management techniques can help. Deep breathing, exercising regularly, and progressive relaxation techniques are simple ways to help you accept stress and reduce its negative effects.

Lark’s stress management program is part of Lark’s programs for healthy living and chronic condition prevention and management. Lark coaches on accepting stress and reducing it, as well as on stress management techniques. Along with eating well and being physically active, stress management is a part of an overall healthy lifestyle.