Unexplained Fatigue

Posted by Dr. Shannon Sarrasin, ND on 2017 Apr 27th

Unexplained Fatigue

Do you suffer from unexplained fatigue and exhaustion? Perhaps you have seen your doctor and after a basic workup you have been told that everything is ok. Unexplained fatigue is a common concern that I see in practice. It is a general symptom that has a multitude of causes.

Let’s dig deeper to understand the root cause of fatigue. Understanding is the first step in creating a health plan that will optimally support you in regaining your strength and vitality.

Adrenal Stress

Have you been burning the candle at both ends? Chronic stress has a negative impact on the adrenal glands and cortisol production. Signs of adrenal dysfunction include afternoon fatigue, feeling “tired and wired”, cold hands and feet, blood sugar sensitivity and blood pressure changes.

Stress is a major cause of fatigue. Chronically elevated cortisol has a breakdown effect on the body and depletes the body at the cellular level affecting mood, hormones, blood sugar and more.

Nutrient Deficiency

A basic assessment involves looking for deficiency of iron and vitamin B12 (note: lab reference ranges may not indicate optimal levels). Deficiency can be due to low levels in the diet or poor digestion/absorption. Women are at an increased risk of iron deficiency if they experience heavy periods. Other nutrient deficiencies that a naturopathic doctor may look for includes magnesium, zinc, selenium, iodine, B vitamins, folate, Omega 3 EFA, vitamin D and protein.

Thyroid Imbalance

Symptoms of low thyroid function include fatigue, cold intolerance, weight gain, sluggish bowels, thinning hair, depression, joint/muscle pain and brain fog. Conventional assessment involves lab testing of TSH. Reference range of this lab can be wide, and a naturopathic doctor will look for optimal levels. In addition, it can be helpful to test freeT3, freeT4 and thyroid antibodies if thyroid dysfunction is suspected.

Brain Health

Brain hormones such as serotonin, dopamine and norepinephrine have an effect on mood, energy, motivation and concentration. Deficiency in these can contribute to mental and physical fatigue.

Blood Sugar

If you miss a snack or a meal are you prone to episodes of fatigue, shakiness, irritability and generally feeling unwell? If so, you may be experiencing hypoglycemia or low blood sugar. Blood sugar sensitivity (both high and low) can affect energy levels. Diet plays a big role in correcting this imbalance.

Mitochondria dysfunction

Mitochondria are the little engines that produce energy in all of our cells. They require nutrients to keep them running efficiently and are damaged by oxidation in the body. If your body is overburdened with stress, toxicity, poor diet or excess alcohol your mitochondria may not be serving you well.


The body restores itself while you sleep. Quality restorative sleep is essential for healthy energy, hormone and brain function. Issues such as insomnia, restless leg syndrome and sleep apnea should be identified and treated.


Immune concerns such as allergies, food sensitivities and auto-immune conditions can lead to fatigue. Screening for chronic infections such as Epstein-Barr virus which causes Mono or Lyme disease may be indicated.

Other causes of fatigue could be due to kidney or liver conditions, chronic fatigue syndrome, poor detoxification, male or female hormone imbalance or others. It is important to discuss your symptoms with your health care practitioner to help you understand the root cause. Treatment is individual and incorporates lifestyle and nutritional recommendations.

Dr. Shannon Sarrasin, ND

Dr. Shannon Sarrasin is a naturopathic doctor who is clinically trained and naturally focused.

She is co-owner of Flourish Naturopathic at Moss Street Healthcare Centre.

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