Fatigue is a symptom that most likely will affect you at some point in your life. Fatigue or tiredness can be a result of an actual medical condition, lifestyle choices, work stressors, family stressors, or a combination of any and all of these. Fatigue in and of itself is not a specific diagnosis unless we are speaking about adrenal fatigue. In most cases, there is an underlying issue that is contributing to the feelings of fatigue or exhaustion. Let’s go over some of the more common reasons that you would feel this way.


One of the more common reasons for fatigue is anemia. There are many types of anemia but the most common are iron or B vitamin deficiency. Both of these result in having either a low red blood cell count and/ or low hemoglobin count. The outcome of having fewer red blood cells circulating is less oxygen so the cells and organs have to work harder – it’s similar to not having enough gas in the engine to make the car go. Running a complete blood count and an iron panel can help determine if you are anemic and need to supplement your diet with iron-rich or b-vitamin-rich foods. In most cases, getting the iron or vitamin B levels up will help to resolve the fatigue. I have seen significant improvement in fatigue levels just by addressing this simple issue. 


Having low thyroid function is likely one of the most common reasons for fatigue, especially in women. The thyroid gland produces thyroid hormones which are responsible for metabolism – energy production.  When the thyroid is functioning suboptimally the level of energy production is also suboptimal. The challenge with thyroid testing is that testing is not always effective at diagnosing due to a wide range of acceptable normal values or only looking at one measurement. 

Naturopathic doctors typically recommend getting the TSH (thyroid-stimulating hormone), free T-4, and free T-3 tests and occasionally reverse T3. These give a better picture of what the thyroid gland and hormones are actually doing. In addition, it may be necessary to measure thyroglobulin and thyroid-peroxidase antibodies to ensure there is not an auto-immune process occurring. 

The other important factor when looking at the lab results is having a range that is looking for optimal health rather than pathology. Often times the lab ranges are so broad that it is difficult to determine if the fatigue is coming from low thyroid function. Naturopathic doctors utilize tighter lab ranges which results in a more effective diagnosis. Having suboptimal thyroid function could be a primary reason for fatigue so it is always a good idea to have your levels measured. 

Adrenal Fatigue

The adrenal glands produce several different hormones. Cortisol is the primary hormone that most people have heard about, aldosterone, adrenaline, and noradrenaline are the other hormones. The hormones play roles in regulating blood pressure, stress response, blood sugar, inflammation, sexual maturation, and maintaining pregnancy. In general, it is rare to have an adrenal disorder that causes disease — when it does happen it is due to over or underproduction of the hormones. 

It is more common to have a functional adrenal issue in which the body is not making quite enough cortisol to feel fabulous. This is called adrenal fatigue and is probably one of the most underdiagnosed causes of fatigue. It’s estimated that up to 80 percent of adults experience adrenal fatigue during their lifetimes, yet it remains one of the most under-diagnosed illnesses in the United States. “The adrenals are known as ‘the glands of stress,'” writes James Wilson in his book Adrenal Fatigue: The 21st Century Stress Syndrome (1). “It is their job to enable your body to deal with stress from every possible source, ranging from injury and disease to work and relationship problems. Your resiliency, energy, endurance and your very life all depend on their proper functioning.”

Doing a simple saliva test will help determine how your adrenal glands are functioning. 


Insomnia is usually characterized by difficulty falling asleep or waking up repeatedly in the middle of the night, combined with unrefreshing sleep and daytime exhaustion. Insomnia, like fatigue, can be more of a symptom than a disorder since it can be associated with many causes. 

Some of the more common causes for insomnia would be sleeping during the day, too much light in the bedroom, too warm of a room, using devices before bedtime exposing your eyes to blue light, or working a night shift. 

Insomnia can also be associated with stress, anxiety, or depression, herbs, imbalanced hormone levels, supplements or medications, caffeine, alcohol, pain, pregnancy, and sleep apnea are other causes of insomnia. 

Getting to and treating the root cause of your insomnia will make a significant difference in your life. Your brain functions better, your mood is better, and your relationships are better. 

Fatigue Wrap Up

As you can see, there are several reasons for being fatigued and believe it or not this is just the tip of the iceberg. The above reasons are some of the more common causes that we see in naturopathic medical practice. 

If you believe your exhaustion is due to one of the above factors contact your local naturopathic doctor so they can get a thorough history from you and run any needed lab tests. This will help to determine the root cause of the fatigue and help the body to return to a state of balance so that you can live your life to the fullest.

(1)  Wilson, James. “Adrenal Fatigue: The 21st Century Stress Syndrome.” Smart Publications, p. 6, 2002.

Dr. Laura Enfield, ND, LAc

Dr. Laura Enfield maintains a naturopathic practice in San Mateo, CA. She specializes in regenerative joint treatments for pain, nutritional IV therapy, and naturopathic care for digestion, fatigue, insomnia, thyroid, and adrenal issues. She is a member of the California Naturopathic Doctors Association where she is the chair of the Public Affairs and Realize a Healthy California Committee. She loves seeing her patient’s health improve with the power of naturopathic medicine!

The information on this site and social media is not intended or implied to be a substitute for professional medical advice, diagnosis, or treatment. All content, including text, graphics, images, and reference links, contained on or available through this web site is for general information purposes only. If you are experiencing a medical emergency, call 911 immediately.,