For many people, stress causes changes in weight. It can lead to either weight gain or weight loss, depending on how your body reacts to it.
Either way, chronic stress is unhealthy, and sudden changes in your weight can be a sign that you’re under more stress than usual.
Read on to learn about how stress affects your body and behavior and why it can cause weight loss. This article will also cover what you can do to relieve stress and stay healthy, even when life gets hard.
Signs of Stress-Induced Weight Loss
It’s not always easy to recognize when you’re stressed. Be on the lookout for sudden, unintentional weight loss, as well as any of the below symptoms of anxiety or stress:
- Gastrointestinal problems (diarrhea, constipation, stomachache, nausea)
- Loss of appetite
- Headaches
- Trouble sleeping
- Decreased sex drive
- Muscle aches and pains
- Muscle tension
- Clenching your jaw
- Grinding your teeth
- Mood changes (depression, mood swings)
- Fatigue
- Nervous movement (fidgeting, tics, etc.)
- Lack of motivation
- Increased illness or infections
- Short-term memory problems (forgetting your keys, missing appointments, etc.)
- Sudden gray hairs
These are all signs that your stress levels are higher than usual, and that stress could be behind your unexplained weight loss.
Why Does Stress Cause Weight Loss?
Stress causes changes to both your biology and your behavior. Together, these changes can lead to sudden, unhealthy weight loss over time.
Here are a few of the ways that stress can cause weight loss.
Fight or Flight Burns Calories
When your brain senses danger, it tells your adrenal glands to release epinephrine (adrenaline). Adrenaline gets your body ready to deal with a threat: it speeds up your heart rate and breathing to send more oxygen to your cells and increases your muscle tension so you’re ready to fight the threat or run away from it[*].
This process is called your fight or flight response. It worked well for our ancestors — it’s great if you’re running from a tiger — but today, most of us deal with less immediate, more long-term psychological stressors (from work, relationships, finances, and so on). Your brain still interprets these stressors as threats, so if you’re chronically stressed, your body stays in a low-level state of fight or flight.
Faster heart rate and breathing, muscle tension, nervous movement, and other symptoms of chronic stress can burn calories over time, causing you to lose weight. The change is more significant than you might think, too — fidgeting while sitting increases energy expenditure by 20-30%[*], and some studies even suggest that fidgeting protects against obesity[*].
Stress Can Cause Digestive Issues
When you feel threatened, your body releases the hormone cortisol (sometimes called your “stress hormone”).
Cortisol redirects blood flow away from your digestive system and toward your brain and muscles. This is your body’s natural stress response, and it makes sense: when you’re in immediate danger, it’s more important to think and move than it is to digest.
However, if you’re under chronic stress, consistently high cortisol levels can cause digestive problems that make it difficult to eat. Side effects of stress on digestion include[*][*]:
- Diarrhea
- Constipation
- Loss of appetite
- Decreased food intake
- Heartburn or reflux
- Nausea
- Vomiting
These symptoms can make it difficult to eat, causing you to lose weight over time.
Stress Can Change Your Eating Habits
Stress also changes your behavior in ways that can make you lose weight.
For example, you may skip lunch because you’re behind on a project at work, or you may be so preoccupied with a problem in your life that you forget to eat.
Not eating enough can worsen symptoms of stress because you aren’t getting the nutrients your body needs.
Tips for Healthy Stress Reduction
If you’re going through a difficult period in your life, it’s worth your time to consciously manage your stress levels.
With the right habits and tools, you can build up your resilience to stress and stay healthy, even in hard times.
Here are three tips for healthy stress management.
Exercise
Physical activity is a cornerstone of good physical and mental health. Research shows that working out lowers your cortisol levels and relieves anxiety, depression, negative mood, high blood pressure, and a variety of other causes and side effects of chronic stress[*].
The type of workout you do doesn’t matter. What’s important is moving your body on a regular basis, whether it’s walking, running, heavy lifting, or a simple at-home bodyweight workout routine.
If you’re struggling to begin an exercise routine, start slow. Set a goal to walk around the block three times a week, and once you do that consistently, work your way up to more vigorous exercise.
Also, if you’re exercising consistently, get in the habit of having a high-quality snack or protein shake afterward to prevent further weight loss.
Mindfulness Meditation
Meditation is a simple way to relieve stress, and studies show that mindfulness meditation is one of the best options.
Mindfulness-based stress reduction (MBSR) is a simple meditation program specifically designed to relieve stress and promote mental wellbeing.
Studies show that MBSR reduces psychological stress, depression, anxiety, and burnout, and improves sleep quality and resilience to future stress[*][*].
Here’s a simple way to practice MBSR:
- Find a quiet spot
- Set a timer for 5 minutes
- Sit comfortably
- Take deep, slow breaths in and out
- Put your attention on your breath
- If other thoughts come in, allow them to pass by and return your focus to your breath
You can do this simple mindfulness practice almost anywhere and it’s a powerful way to relieve stress.
Deeper Sleep
Your body and brain rebuild and recover deeply during sleep, and improving your sleep quality can help you counter the effects of stress. This is especially important if you’re having trouble sleeping, which is one of the most common symptoms of chronic stress.
To improve your sleep quality, try this routine:
- No caffeine after 2 PM[*]
- Use blackout curtains and cover up light sources (like digital alarm clocks or WiFi routers) to make your bedroom as dark as possible[*]
- Take 200-400mg of magnesium an hour before bed[*][*]
- Take 1 mg of melatonin an hour before bed [*]
Tips for Healthy Weight Gain
If you find that stress is making you skip meals or forget to eat, you may want to create more structure around your eating habits.
Make sure you’re eating at least two big meals a day and prioritize high-quality protein, healthy fats, and vegetables. Good nutrition will make your body more resilient to stress.
If you’re not skipping meals but you’re still losing weight, consider adding more calories to your diet than you would normally eat. Stick to healthy foods; eating fast food, packaged snacks, or empty carbohydrates (especially refined carbs like sugar) can compromise your immune system and make the effects of stress worse for you, not better[*].
You may also want to talk to a nutritionist about your diet. He or she can help you find a nutrition plan that promotes healthy weight gain.
When to Seek Medical Attention
Talk to your doctor if you lose more than 5% of your body weight without trying in a 6-month period[*].
You should also talk to your doctor if:
- You’re becoming overly focused on food or weight loss as a way of coping with stress
- You experience panic attacks, or other possible signs of an anxiety disorder (don’t worry; doctors and therapists can help)
- You have chest pain, chronic muscle pain, or persistent headaches/migraines
- You find yourself using drugs or alcohol to manage the stress in your life
A doctor can help you find ways to better manage your stress and get you on a plan to get back to a healthy weight.
The Takeaway
Stress can cause fluctuations in your weight, whether that’s unwanted weight loss or weight gain.
Managing stress and prioritizing a healthy, higher-calorie diet can help you regain lost weight. However, if you lose more than 5% of your body weight in a 6-month period or you feel that stress is significantly impacting your life, consider talking to a healthcare professional.
A doctor, therapist, nutritionist, or other expert can help you cope with stress and get yourself to a healthy state, both physically and mentally.