4 Ways Stress Is Affecting Your Thyroid

Stress is a good thing. Stress enables you to get fitter, smarter and pushes you to be your best. However, too much stress or inability to cope with stress, can send your body into a tailspin of fatigue, brain fog or unexplained weight gain.

Your metabolism is set by your thyroid gland, and too much stress (or lack of adequate recovery), can begin to negatively impact your thyroid. This is referred to as thyroid dysfunction, an early warning sign that your body is struggling to keep up.

Your thyroid is affected by your body’s stress control system the HPA-axis (hypothalamic-pituitary-adrenal axis), a dynamic and complex system that governs your body’s homeostasis and your reaction to stress. 

Excessive stress slows the function of your hypothalamus – the master hormone conductor of the brain – and your pituitary, which is responsible for controlling thyroid function.

Stress isn’t just the inability to cope or being too busy. If you suffer from digestive problems (e.g. gas, bloating, etc.), chronic inflammation, poor blood sugar control, poor immunity or autoimmune conditions, these are all “stressors” that impact the HPA-axis and ultimately your thyroid function.

If we dig a little deeper, we also find that stress inhibits your thyroid gland’s ability to convert the inactive T4 thyroid hormone into the active T3 hormone in the body. Poor conversion of T4 to the active T3 leads to sluggish thyroid function and increased likelihood of hypothyroid symptoms, such as cold hands and feet, weight gain, fatigue, and less frequent bowel movements or constipation.

Let’s take a closer look at 4 common ways excessive or chronic stress negatively impacts your thyroid.

work stress

  1. You’re Too Busy

In today’s 24/7 society, you’re constantly on the go and busier than ever before. Stress is not simply the inability to cope, it’s also how “busy” you are throughout your day. While technology and connectivity can provide you with incredible tools to be more productive, it can also leave your brain and body stuck in “stimulation” overload.

If you wake up early to get to the gym or prep your kids for school (or both!), if you’re under constant pressure at work, if you’re always rushing home to make it in time for dinner, it's easy to see how life has become a daily 18-hour sprint. 

This leads to constant activation of the body’s “fight or flight” sympathetic nervous system, and the production of excessive stress hormones (e.g. adrenaline and cortisol), which takes its toll on the health of your thyroid. Sometimes, slowing down is the best thing you can do for your health.


  1. You’re Too Caffeinated

This is a common theme for many people: you wake up tired, you need a boost of energy and you reach for a morning cup of coffee. While coffee has a vast array of health benefits, you can get too much of a good thing.

When life gets busy and your body is in sympathetic overdrive, you naturally crave caffeine (and sugar) to keep yourself going. Too much caffeine also impacts your sleep quality at night. 

If you consume coffee in the afternoon, it’s important to know the half-life of caffeine (the time it takes to reduce by one half the original value) is about six-eight hours, meaning your 3 p.m. cup of coffee (approx. 150mg of caffeine) will still leave you with 75mg of caffeine in the body at 9-11 p.m. While that’s great if you’re hitting the dance floor, it’s not great for deep sleep or the health of your thyroid. 

Aim for 3-4mg per kilogram body weight per day. For example, a 60kg female should aim for 180-240mg of caffeine daily, which amounts to about 1.5 Americanos in a day. The good news is, decaf coffee provides all the health benefits without the extra caffeine.


  1. You Don’t Sleep Long Enough

Sleep is the most effective tool you have to rebuild the proverbial candle you’re burning at both ends during the day. The only problem is, you’re likely not getting enough.

The average person now survives on 6.5 hours of sleep per night, about 1.5 hours less sleep than our grandparents had two generations ago. Over the course of a year, that is 500 hours less sleep than you should be getting (no wonder you’re tired!).

If you don’t sleep enough or fail to adequately recover, your metabolism (i.e. thyroid) and resting metabolic rate will slow, leaving your sluggish and feeling like you’re stuck in the mud. 

The National Sleep Foundation recommends 7-9 hours nights, so aim to get to bed by 11:00 p.m. most nights of the week to upgrade recovery and support a healthy thyroid.


  1. You Exercise Too Much

For many people, adding more movement to their day –walking, strength training, yoga – is a great way to relieve stress and improve resiliency (capacity to cope with stress). If you suffer from a sluggish thyroid, you may be struggling with weight gain and subsequently decide to add more exercise to shed those unwanted extra pounds.

However, if you’re already an avid exerciser, adding more training volume without considering how you periodise or plan the sessions, often makes the problem worse (not better).

In fact, you likely don’t need more exercise. You simply need more efficient exercise.

In general, reducing the workout time and increasing the workout intensity are important principles for those struggling with slow thyroid function. Symptoms include persistent fatigue, brain fog, inability to lose weight, cold hands and feet, etc.

Stress is not the enemy. However, too much stress from being too busy, too caffeinated, insufficient sleep or training too much will compromise your resiliency and may ultimately lead to symptoms of a sluggish thyroid.

The good news is you likely don’t have a frank hypothyroid medical condition, you simply need to get back to the fundamentals, prioritise rest and recovery, and develop a sound exercise plan to keep up in your own fast-paced world without sacrificing your health.


Dr. Marc Bubbs ND, MS(c), CISSN, CSCS