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Racing thoughts and low-grade fear are all-too-familiar signs of anxiety. But the effects of anxiety aren’t all in your head—chronic tension and stress can manifest in physical ailments you might not have connected with your ongoing nervousness.
What’s the link? It starts with a primal survival mechanism called the fight-or-flight response—an evolutionary tool that allowed us to respond rapidly to life-or-death situations, like big, scary animals with giant teeth. In the presence of danger, real or perceived, the brain sounds an alarm, sending distress signals to the adrenals—tiny glands that sit on top of the kidneys. The adrenal glands then release adrenaline and cortisol—stimulating, alerting hormones that get the body ready to fight (or run) for your life. Heart rate and blood pressure escalate as the heart amps up blood flow to the muscles and vital organs. Respiration increases as the lungs work to pump oxygen into the muscles and brain, to enhance alertness and prepare for physical action. Once the threat subsides, the parasympathetic nervous system puts on the brakes to dampen the stress response.
That’s all well and fine if you’re truly in danger. But sometimes the body overreacts to everyday stressors—family conflicts, pending deadlines, traffic jams—perceiving them as life-threatening. The problem: being in a constant state of alert takes its toll and, left unchecked, can increase the risk for mood disorders and chronic illnesses like high blood pressure, heart disease, diabetes and cancer.
The bottom line: it’s not all in your head. Here’s how anxiety can impact your health—plus, simple ways to tame tension and put the brakes on the fight-or-flight.
1. Sleep Issues
The body’s natural levels of cortisol follow a daily rhythm—higher in the morning, lower at night in preparation for rest. But in the presence of chronic anxiety and stress, that rhythm gets disrupted—and so does sleep. Plus, worries, fears and racing thoughts make it that much harder to doze off. Even worse: sleep deprivation boosts cortisol production, keeping your body in a state of hyperarousal and further impacting slumber. Over time, lack of restful sleep increases the risk of depression, high blood pressure, diabetes and stroke.
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2. Unexplained Weight Gain
Anxiety and chronic stress may be the reason you just can’t shed that extra ten pounds. Elevated cortisol levels prompt the body to store fat, especially around the belly; digestive disturbances from ongoing stress also disrupt gut bacteria, encouraging weight gain. Anxiety-related fatigue and lack of energy mean you’re exercising less, and sleep deprivation is linked with muscle loss and fat gain. Plus, stress-eating aimed at soothing inner turmoil can pack on extra pounds—especially if you’re eating cookies, ice cream and tension-taming goodies.
3. Breathing Problems
When anxiety prompts a fight-or-flight response, speed and depth of breathing escalate, supplying tissues with extra oxygen to prepare for action. The result: shortness of breath, wheezing tightness in your chest, and a feeling that you can’t quite catch your breath. Plus, increased breathing—especially in the absences of subsequent fighting or fleeing— decreases blood supply to the brain and can lead to dizziness, blurred vision, confusion, even a sense of unreality. And there’s a well-established association between anxiety and respiratory ailments, including asthma.
Stress hormones cause the body to direct blood flow away from the intestines and toward vital organs like the brain, heart and lungs, slowing normal gut contractions and impacting bowel movements. Ongoing anxiety may also increase intestinal permeability and influence gut bacteria balance, both linked with constipation. Plus, when you’re anxious or stressed, you’re less likely to eat well, exercise or stay adequately hydrated—all factors in regular bowel movements. And lack of sleep depresses bowel movement and increases the chances of constipation.
5. Frequent Colds and Flu
Anxiety and chronic tension can weaken the immune system, leaving you open to near-constant colds, flu and stomach bugs. When you’re operating in fight-or-flight, elevated stress hormones dampen the body’s production of immune cells that ward off foreign invaders, including pathogens. And consistently elevated cortisol can promote inflammatory chemicals that further compromise the immune response. Not only does anxiety leave you more susceptible to infections; over time, suppressed immune function can increase your risk of heart disease, cancer and other diseases.
In a state of fight-or-flight, muscles around the spine go on hyper alert, tensing in preparation for running for your life. That ongoing rigidity can lead to muscle tightness and pain. Plus, when you’re anxious or stressed, breathing patterns shift, exacerbating muscles tension and strain, especially in the mid- and lower back. Anxiety is linked with a greater risk of back problems, and people with lower back pain are more likely to have higher levels of anxiety and depression.
The link between stress and migraines is well-established, and other kinds of headaches can also be triggered by anxiety. Rigid muscles in your neck and shoulders restrict blood flow and can cause spasms around the nerves in the neck and head; clenching your jaw when you’re tense only exacerbates head pain. Plus, sleep disturbances—common when you’re anxious—can lower pain threshold and set off tension headaches and migraines.
8. Stomach Woes
Indigestion, heartburn or nausea aren’t always caused by diet. In a state of high anxiety, digestion is suppressed as the body diverts energy and resources to the limbs and vital organs. Stress also amps up stomach acid, leading to heartburn and indigestion, and chronic tension can impact gut bacteria, causing digestive problems. Over time, high levels of anxiety increase the risk for digestive disorders, including Irritable Bowel Syndrome (IBS) and stomach ulcers.
Move from fight-or-flight stress into serenity, with these simple ways to ease anxiety.
- Take a walk, hike or run; physical activity relieves muscle tension and lessens stress, and being in nature promotes serenity.
- Avoid caffeine, known to elevate anxiety; stick to decaf coffee, or less-stimulating green tea (also high in soothing L-theanine).
- Try mind-body exercises; yoga, tai chi and qi gong encourage deep breathing, calm focus and flowing, relaxing movements.
- Focus on your breath; deep belly breathing and other practices slow heart rate and respiration, encouraging tranquility.
- Elicit your relaxation response: try mindfulness meditation, repeat a calming word like “peace” or “love,” or visualize a restful scene.
- Enlist your network; support from friends, family and trusted co-workers promote resilience during times of stress.